- NbCl5 as an efficient catalyst for chemoselective synthesis of 1,1-diacetates under solvent-free conditions
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A mild and efficient method for the chemoselective preparation of 1,1-diacetates catalyzed by NbCl5(5mmol%) under solvent-free conditions has been developed. The yields are in the range of 93-98%. This protocol offered several advantages, including low catalyst loading, good yields, short reaction times, and environmentally friendliness.
- Gao, Shu-Tao,Zhao, Ying,Li, Chao,Ma, Jing-Jun,Wang, Chun
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- Indium tribromide as a highly efficient and versatile catalyst for chemoselective synthesis of acylals from aldehydes under solvent-free conditions
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A mild and efficient method has been developed for the chemoselective preparation of acylals from aldehydes in the presence of catalytic amounts (0.01-1.0 mol%) of InBr3 under solvent-free conditions in very good to excellent yields.
- Yin, Liang,Zhang, Zhan-Hui,Wang, Yong-Mei,Pang, Mei-Li
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- Solvent-free catalytic preparation of 1,1-diacetates using a silica-supported functional ionic liquid as catalyst
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An efficient and convenient preparation of acylals from aldehydes and acetic anhydride, under solvent-free conditions, in the presence of a silica-supported functional ionic liquid, Si-[SbSipim][PF6], is reported. Si-[SbSipim][PF6] acts as a catalyst and can be recovered and reused four times without apparent loss of its catalytic activity.
- Kang, Li Q.,Cai, Yue Q.,Cheng, Lin
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- A rapid and convenient synthesis of 1,1-diacetates from aldehydes and acetic anhydride catalyzed by PVC-FeCl3 catalyst
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A variety of aldehydes can be converted into 1,1-diacetates rapidly and conveniently in the presence of catalytic amounts of poly(vinyl chloride) supported ferric chloride reagent at room temperature in excellent yields.
- Li
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- 1,3-Dibromo-5,5-dimethylhydantoin as catalyst for the conversion of aldehydes to their 1,1-diacetates (acetylals) under solvent-free and neutral conditions
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Highly efficient and mild acetylation of aldehydes with acetic anhydride catalysed by 1,3-dibromo-5,5-dimethylhydantoin (DBH) was performed under neutral conditions to produce corresponding 1,1-diacetates (acetylals) in good to excellent yields.
- Azarifar, Davood,Ghasemnejad, Hassan,Ramzanian-lehmali, Farhad
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- An efficient method for the chemoselective synthesis of acylals from aromatic aldehydes using bismuth triflate
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Aromatic aldehydes are smoothly converted into the corresponding acylals in good yields in the presence of 0.10 mol% Bi(OTf)3·xH2O. Ketones are not affected under the reaction conditions. The highly catalytic nature of bismuth triflate and the fact that it is relatively non-toxic, easy to handle and insensitive to small amounts of air and moisture makes this procedure especially attractive for large-scale synthesis.
- Carrigan, Marc D.,Eash, Kyle J.,Oswald, Matthew C.,Mohan, Ram S.
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- A rapid preparation of acylals of aldehydes catalysed by Fe3+- montmorillonite
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Aldehydes can be converted to acylals by treatment with acetic anhydride in the presence of Fe3+-montmorillonite in excellent yield at room temperature.
- Li, Tong-Shuang,Zhang, Zhan-Hui,Gao, Yong-Jian
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- A novel and efficient conversion of aldehydes to 1,1-diacetates catalyzed with FeCl3/SiO2 under microwave irradiation
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1,1-Diacetates (3) are effectively synthesized in few minutes by acylation reaction of aldehydes with acetic anhydride in the presence of FeCl3/SiO2 under microwave irradiation.
- Wang, Cunde,Li, Minghua
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- Synthesis of 1,1-Diacetates from Aldehydes using Trimethylchlorosilane and Sodium Iodide as Catalyst
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A variety of aldehydes react with acetic anhydride in the presence of trimethylchlorosilane and sodium iodide or trimethylchlorosilane alone to afford 1,1-diacetates in excellent yields.
- Deka, Nabajyoti,Borah, Ruli,Kalita, Dipok J.,Sarma, Jadab C.
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- A convenient and efficient protocol for the synthesis of acylals catalyzed by Br?nsted acidic ionic liquids under ultrasonic irradiation
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The synthesis of acylals (1,1-diacetates) via the reactions of aldehydes with acetic anhydride was carried out in 85-97% yields at room temperature under ultrasound irradiation catalyzed by the Br?nsted acidic ionic liquid [bmpy]HSO4. This method provides several advantages, such as solvent-free conditions, operational simplicity, higher yields, and reduced environmental consequences. The ionic liquid was recovered and reused.
- Borikar, Sanjay P.,Daniel, Thomas
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- VSO4.5H2O: A mild and efficient catalyst for chemo-selective conversion of aldehydes to 1,1-diacetates
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Protection of aliphatic and aromatic aldehydes as 1,1-diacetates using VSO4.5H2O under solvent-free conditions is carried out. The products are obtained in good to excellent yields. Ketones are not affected under these conditions.
- Heravi, Majid M.,Bakhtiari, Khadijeh,Benmorad, Tina,Oskooie, Hossein A.
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- Indium trichloride catalyzed chemoselective conversion of aldehydes to gem-diacetates
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Aldehydes are chemoselectively converted into the corresponding gem-diacetates at ambient temperature in high to quantitative yields using a catalytic amount of indium(III) chloride. The deprotection of the resulting gem-diacetates is achieved using the s
- Yadav,Reddy, B. V. Subba,Srinivas
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- A rapid, convenient and chemoselective synthesis of acylals from aldehydes catalyzed by reusable nano-ordered MCM-41-SO3H
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Acylals were prepared by direct condensation of aldehydes with acetic anhydride using nano-ordered MCM-41-SO3H as a heterogeneous catalyst under solvent-free conditions at room temperature in a very short reaction time and excellent yields. The catalyst is recyclable, non-toxic, neither air nor moisture sensitive, and easy to handle. High chemoselectivity toward aldehydes in the presence of ketones is another advantage of the present method which provides selective protection of aldehydes in their mixtures with ketones.
- Tourani, Hesam,Naimi-Jamal, Mohammad Reza,Dekamin, Mohammad Ghorban,Amirnejad, Meysam
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- Silica sulfuric acid as an efficient heterogeneous catalyst for the synthesis of 1,1-diacetates under solvent-free conditions
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An efficient method for the preparation of acylals from different aldehydes in the presence of silica sulfuric acid and acetic anhydride under solvent-free conditions is reported. Georg Thieme Verlag Stuttgart.
- Hajipour, Abdol R.,Zarei, Amin,Khazdooz, Leila,Mirjalili, Bi Bi F.,Sheikhan, Nafise,Zahmatkesh, Saeed,Ruoho, Arnold E.
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- Chemoselective synthesis of geminal diacetates (acylals) using eco-friendly reusable propylsulfonic acid based nanosilica (SBA-15-Ph-PrSO3H) under solvent-free conditions
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An expeditious method for the acetylation of aldehydes by mesoporous solid sulfonic acid (SBA-15-Ph-PrSO3H) under solvent-free reaction conditions was described. The route furnished selectively and in excellent yields the corresponding 1,1-diacetates starting from aldehydes and acetic anhydride using the environmentally friendly catalyst. The catalyst was found to be highly active and selective and could be recycled several times.
- Zareyee, Daryoush,Moosavi, Sayed M.,Alaminezhad, Alireza
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- An efficient method for synthesis of acylals from aldehydes using multi-walled carbon nanotubes functionalized with phosphonic acid (MWCNTs-C-PO3H2)
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MWCNTs-C-PO3H2 has been used as an efficient, heterogeneous and reusable nanocatalyst for synthesis of acylals from aldehydes under solvent-free conditions at room temperature. A wide range of aldehydes was studied and corresponding products were obtained in good to excellent yields in short reaction times. Nanocatalyst can be easily recovered by centrifuge and reused for subsequent reactions for at least five times without deterioration in catalytic activity. The major advantages of the present method are high yields, short reaction time, recyclable catalyst and solvent-free reaction conditions at room temperature.
- Dehghani, Farzaneh,Sardarian, Ali Reza,Doroodmand, Mohammad Mehdi
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- An efficient method for the synthesis of acylals from aldehydes using silica-supported perchloric acid (HClO4-SiO2)
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The synthesis of acylals from structurally diverse aldehydes has been performed in excellent yields under solvent-free conditions using HClO4-SiO2 as a mild, convenient, reusable, and heterogeneous catalyst. The procedure is operationally simple, environmentally benign and has the advantage of enhanced atom utilization. Furthermore, the catalyst can be recovered simply and reused efficiently a number of times without appreciable loss of activity.
- Kamble, Vinod T.,Jamode, Vasant S.,Joshi, Neeta S.,Biradar, Ankush V.,Deshmukh, Rameshchandra Y.
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- Formation of benzylidenes-diacetates catalyzed by activated zeolite "LZY-562" and clay (K10/ZnCl2): An unexpected functional selectivity
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Activated zeolites LZY-562 and clay montmorillonite K10 at room temperature without solvent catalyzes the synthesis of benzylidenesdiacetates from carbonyl compounds. A chemoselectivity was observed between aldehydes and ketones, between the different aldehydes and ketones as well.
- Dokari,Hammadi,Benferrah,Rachedi
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- Solvent-free catalytic preparation of 1,1-diacetates from aldehydes using a Wells-Dawson acid (H6P2W18O62·24H 2O)
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Aromatic and aliphatic aldehydes are transformed in 1,1-diacetates (acylals) in mild conditions, by a treatment with acetic anhydride and a Wells-Dawson acid (H6P2W18O62·24H 2O). gem-Diacetylation proceeds in Ac2O with a little as 1% mol Wells-Dawson acid at room temperature and under solventless conditions, obtaining very good to excellent yields (88-98%) of 1,1-diacetates (19 examples). Neither 4-dimethylaminobenzaldehyde nor ketones react under the same conditions.
- Romanelli, Gustavo P.,Thomas, Horacio J.,Baronetti, Graciela T.,Autino, Juan C.
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- Montmorillonite Clay Catalysis. Part 4.11 An Efficient and Convenient Procedure for Preparation of 1,1-Diacetates from Aldehydes
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An easy preparation of 1,1-diacetates from aldehydes with montmorillonite clays as catalysts has been carried out in excellent yield.
- Zhang, Zhan-Hui,Li, Tong-Shuang,Fu, Cheng-Guang
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- PEG-supported sulfonic acid as an efficient and recyclable catalyst for the synthesis of 1,1-diacetates under solvent-free conditions
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An operationally simple, efficient, and environmentally benign synthesis of 1,1-diacetates in good yields by reaction of different aldehydes with acetic anhydride in the presence of PEG-supported sulfonic acid under solvent-free conditions is described. C
- Wang, Qiu-Ying,Sheng, Shou-Ri,Wei, Mei-Hong,Xie, Zhong-Li,Liu, Xiao-Ling
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- Microwave induced synthesis of geminal diacetates from aldehydes using envirocat EPZ10 without solvent
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A simple, efficient, and environmentally friendly synthesis of geminal diacetates using Envirocat EPZ10 under microwave activation and solvent-free conditions is described. Easy separation and recyclability of the catalyst, high reaction rates, high yields, and easy work-up are important advantages of this method.
- Bandgar, Babasaheb P.,Makone, Sangita S.,Kulkarni, Sulakshana R.
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- Copper(II) tetrafluoroborate-catalyzed formation of aldehyde-1,1-diacetates
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Aldehyde 1,1-diacetates are farmed in excellent yields from aldehydes and acetic anhydride under solvent-free conditions at room temperature in short times in the presence of a catalytic amount of copper(II) tetrafluoroborate hydrate.
- Chakraborti, Asit K.,Thilagavathi, Ramasamy,Kumar, Raj
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- Conjugate addition of indole to α,β-unsaturated ketones catalyzed bylewis acid immobilized on a biorenewable support
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Sulfonated carbonaceous solid acid was prepared straightforwardly from household granulated sucrose through a one-pot carbonization-sulfonation process. The performance of this solid Bronsted acid was tested by the 1,1-diacylation of aldehydes. Lewis acid, such as indium chloride, was supported on sucrose- derived carbonaceous solid acid through anion metathesis and successfully applied to the conjugate addition of indole to α,β- unsaturated ketones.
- Li, Bei-Yao,Zhang, Miao,Yan, Xin-Min,Peng, Yan-Qing
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- An efficient and convenient procedure for preparation of 1,1-diacetates from aldehydes catalysed by expansive graphite
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An easy preparation of 1,1-diacetates from aldehydes has been carried out in excellent yield under catalysis of expansive graphite at room temperature.
- Jin, Tong-Shou,Du, Gui-Ying,Zhang, Zhan-Hui,Li, Tong-Shuang
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- Synthesis of 1,1-diacetates using a new combined catalytic system: Copper p-toluenesulfonate/HOAc
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Copper p-toluenesulfonate acetic acid has been established as an efficient combined catalytic system for chemoselective conversion of aldehydes to diacetates in high yields at ambient temperature in short reaction times. For the catalytic system, the amount of copper p-toluenesulfonate reduced to 0.3 mol%. After the reaction, copper p-toluenesulfonate can be easily recovered and reused for at least 10 runs. Copyright Taylor & Francis Group, LLC.
- Wang, Min,Song, Zhiguo,Gong, Hong,Jiang, Heng
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- Amberlyst-15-catalyzed efficient synthesis of 1,1-diacetates from aldehydes
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Amberlyst-15 was found to be an efficient catalyst for acylation reaction of aldehydes with acetic anhydride at room temperature in dichloromethane.
- Reddy, A. Vijender,Ravinder,Reddy, V. L. Niranjan,Ravikanth,Venkateswarlu
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- Ytterbium perfluorooctanesulfonate catalyzed synthesis of acylals from aldehydes and acetic anhydride in a fluorous biphasic system
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Ytterbium perfluorooctanesulfonate [Yb(OPf)3] catalyses the highly efficient synthesis of acylals from aldehydes and acetic anhydride in a fluorous biphase system (FBS) composed of toluene and perfluorodecalin. The fluorous phase containing the fluorous catalyst is easily separated and can be reused several times without significant loss of catalytic activity.
- Yi, Wen-Bin,Yin, Ya-Qing,Cai, Chun
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- RuCl3·xH2O: A new efficient catalyst for facile preparation of 1,1-diacetates from aldehydes
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An efficient, facile preparation of aldehyde 1,1-diacetates (acylals) in excellent yields catalyzed by RuCl3·xH2O is described. Ketones do not react under these conditions. Copyright Taylor & Francis Group, LLC.
- Saini, Anil,Kumar, Sanjay,Sandhu, Jagir S.
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- An efficient and practical procedure for synthesis of 1,1-diacetates from aldehydes catalyzed by zirconium sulfate tetrahydrate-silica gel
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A facile and efficient procedure for synthesis of 1,1-diacetates from aldehydes with acetic anhydride was described using zirconium sulfate tetrahydrate-silica gel as catalyst in excellent yields under mild reaction conditions.
- Jin, Tongshou,Feng, Guoliang,Yang, Mina,Li, Tongshuang
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- PEG-SO3H as an efficient and reusable catalyst for chemoselective synthesis of 1,1-diacetates
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An efficient and convenient procedure of the synthesis of 1,1-diacetates from aromatic aldehydes and acetic anhydride under mild and solvent-free conditions at room temperature, in the presence of PEG-SO3H is reported. PEG-SO3H acts as a catalyst and can be recovered and reused eight times without apparent loss of its catalytic activity.
- Zong, Ying-Xiao,Wang, Jun-Ke,Niu, Yu-Ying,Li, Zheng-Liang,Song, Zheng-En,Quan, Zheng-Jun,Wang, Xi-Cun,Yue, Guo-Ren,Pan, Yi
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- A remarkable HBF4-SiO2-catalyzed synthesis of acylals from aldehydes under solvent-free conditions
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HBF4-SiO2 has been found to be an outstanding catalyst for the protection of carbonyl compounds as acylals under entirely solvent-free conditions. Some of the major advantages of this procedure are high yields, ease of operation, high chemoselectivity, high atom efficiency, and compatibility with other protecting groups. Georg Thieme Verlag Stuttgart.
- Kamble, Vinod T.,Bandgar, Babasaheb P.,Joshi, Neeta S.,Jamode, Vasant S.
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- [HSO3-pmim][CH3SO3] as an efficient catalyst for chemoselective synthesis of 1,1-diacetates under ultrasound irradiation
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A mild and efficient method for the chemoselective preparation of 1,1-diacetates catalyzed by 1-methyl-3-(3- sulfopropyl)-imidazolium methyl sulfate under ultrasound irradiation has been developed. The yields are ranged in 90%-98%. This protocol offered several advantages including low catalyst loading, high yields, short reaction time and environmentally benign approach.
- Li, Chao,Guo, Tao,Zhou, Xin,Wang, Chun,Ma, Jing-Jun,Li, Jin-Bin
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- Cupric sulfate pentahydrate: A mild and efficient catalyst for the chemoselective synthesis of 1,1-diacetates from aldehydes in a solvent-free system
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Cupric sulfate pentahydrate was found to be an efficient catalyst for the protection of aldehydes as 1,1-diacetates in high yields in a solvent-free system at room temperature. Ketones are not affected under these reaction conditions. Springer-Verlag 2006.
- Heravi, Majid M.,Taheri, Shima,Bakhtiari, Khadijeh,Oskooie, Hossein A.
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- A simple and fast method for protection of aldehydes as 1,1-diacetates using cerium(IV) sulfate as an efficient and reusable inorganic catalyst
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A simple, green, and very fast method for protection of aryl aldehydes as 1,1-diacetates promoted by cerium(IV) sulfate tetrahydrate, Ce(SO 4)2·4H2O, as a novel inorganic solid acid catalyst at room temperature and under solvent-free conditions is described. The present methodology offers several advantages, such as a simple procedure with an easy workup, very short reaction times, high yields, and the absence of any volatile and hazardous organic solvents. Copyright Taylor & Francis Group, LLC.
- Saburi, Elahe,Davoodnia, Abolghasem,Tavakoli-Hoseini, Niloofar
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- Polystyrene-supported, Al(OTf)3-catalyzed chemoselective synthesis of acylals from aldehydes
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Cross-linked polystyrene-supported aluminium triflate [Ps-Al(OTf)3] has been shown to be a mild, efficient, and chemoselective heterogeneous Lewis acid catalyst for acetylation of aldehydes with acetic anhydride. The catalyst can be recovered simply and reused efficiently at least five times without any noticeable loss of catalytic activity. Copyright Taylor & Francis Group, LLC.
- Boroujeni, Kaveh Parvanak
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- Highly efficient and chemoselective conversion of aldehydes to acylals catalyzed with tungsten hexachloride (WCL6)
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Different types of aldehydes react chemoselectively with acetic anhydride in the presence of a catalytic amount of tungsten hexachloride (WCl6) to produce the corresponding gem-diacetates in good to excellent yields.
- Karimi, Babak,Ebrahimian, Gholam-Reza,Seradj, Hassan
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- Aluminum dodecatungstophosphate (AlPW12O40) as an efficient heterogeneous inorganic catalyst for the chemoselective synthesis of geminal diacetates (acylals) under solvent-free conditions
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An efficient and chemoselective preparation of acylals from structurally different aldehydes in the presence of AlPW12O40 and acetic anhydride was achieved easily in high yields at room temperature under solvent-free conditions.
- Firouzabadi, Habib,Iranpoor, Nasser,Nowrouzi, Farhad,Amani, Kamal
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- A versatile and practical synthesis of 1,1-diacetates from aldehydes catalyzed by cyanuric chloride
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Structurally diverse aldehydes are successfully converted into 1,1-diacetates with acetic anhydride using cyanuric chloride as a mild, convenient and inexpensive catalyst under solvent-free conditions. The noteworthy features of the present system are shorter reaction times, and mild and solvent-free conditions. Furthermore, it offers chemoselective protection of aldehydes.
- Bandgar, Babasaheb P.,Joshi, Neeta S.,Kamble, Vinod T.
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- Diacetates from aldehydes in the presence of zeolites
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An easy preparation of diacetates from aldehydes and acetic anhydride in the presence of zeolites is reported.
- Pereira,Gigante,Marcelo-Curto,Carreyre,Perot,Guisnet
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- SiO2@FeSO4 nano composite as nanocatalyst for the green synthesis 1,1-diacetates from aldehydes under solvent-free conditions
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Aldehydes compounds selective converted to 1,1-diacetates as protective reagent with SiO2@FeSO4 nano composite as effective nano catalyst at room temperature under solvent-free condition and acetic anhydride (Ac2O) as acet
- KarimKoshteh, Mostafa,Bagheri, Marziyeh,Zeynizadeh, Behzad
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- Ultrasound-assisted synthesis of acylals from aldehydes using Mg(CH 3SO3)2-HOAC
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An efficient method for the synthesis of acylals from different aldehydes and acetic anhydride in the presence of magnesium methanesulfonate-acetic acid under ultrasound irradiation at room temperature is achieved. Only 1.5mol% of magnesium methanesulfonate and a small quantity of acetic acid are needed to effect the reaction. Selective conversion of aldehydes is observed in the presence of ketones. The catalyst remains active and exhibits no substantial loss of activity or selectivity in up to three reaction cycles.
- Liu, Qing,Ai, Hong-Mei,Feng, Shuai
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- High-valent titanium(IV)salophen: An efficient catalyst for rapid conversion of aldehydes to 1,1-diacetates with acetic anhydride
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In the present work, a mild and highly efficient method for protection of aldehydes with acetic anhydride in the presence of high-valent titanium (IV) salophen trifluoromethanesulfonate, [TiIV(salophen)(OTf) 2], at room temperature is reported. Under these conditions, different aldehydes bearing electron-withdrawing and electron-donating substituents were reacted with acetic anhydride and the corresponding 1,1-diacetates were obtained in good to excellent yields. The results showed that the yields were higher for aldehydes bearing electron-withdrawing substituents such as nitro, chloro, bromo and 3-methoxy, while aldehydes containing electron donating groups such as 4-methoxy and 4-methyl produced the lower yields. The catalyst was reused several times without loss of its catalytic activity.
- Yadegari, Maryam,Moghadam, Majid,Tangestaninejad, Shahram,Mirkhani, Valiollah,Mohammadpoor-Baltork, Iraj
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- A facile and efficient conversion of aldehydes into 1,1-diacetates (acylals) using iron(III) fluoride as a novel catalyst
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Aldehydes are smoothly converted into the corresponding 1,1-diacetates (acylals) in high yields in the presence of a catalytic amount (0.1 mol-%) of iron(III) fluoride at room temperature. The noteworthy features of the present system are shorter reaction times, chemoselective protection of aldehydes, and solvent-free conditions. The procedure is especially useful for large-scale syntheses as the catalyst is highly effective from the view of activity, selectivity, reusability, and economy in the preparation of 1,1-diacetates (acylals). CSIRO 2007.
- Kamble,Tayade,Davane,Kadam
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- Heteropolyacid encapsulated into mesoporous silica framework for an efficient preparation of 1,1-diacetates from aldehydes under a solvent-free condition
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Acylals were prepared from aliphatic and aromatic aldehydes using heteropolyacid (SiPW-8) encapsulated into the framework of mesoporous silica as catalysts in a solvent-free procedure. The catalyst was very effective and reusable for the production of 1,1-diacetates from aldehydes under a mild reaction condition.
- Wang, Jianmin,Yan, Liang,Qian, Guang,Yang, Keli,Liu, Haitao,Wang, Xiaolai
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- Conjugate polymer-supported acid catalysts: An efficient and reusable catalyst for the synthesis of geminal diacetates (acylals) under solvent-free conditions
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A comparative study on the catalytic activity of conducting polyaniline (PANI), polypyrrole (PPY), and poly-(3,4-ethylenedioxythiophene) (PEDOT) salts as solid acid catalysts for the synthesis of 1,1-diacetates (acylals) under solvent-free conditions has been presented. Use of the polypyrrole and poly-(3,4-ethylenedioxythiophene) salts as solid acid catalysts is reported for the first time. Preparation, recovery, and reusability of the catalysts were found to be good. Copyright Taylor & Francis Group, LLC.
- Nabid, Mohammad Reza,Rezaei, Seyed Jamal Tabatabaei,Abedi, Mahvash
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- An efficient conversion of aldehydes to their corresponding acylals with P2O5/SiO2 under mild condition
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A combination of P2O5 and SiO2 was used for an efficient conversion of aldehydes to their corresponding acylals with excellent yields at room temperature under mild conditions.
- Mirjalili, Bibi Fatemeh,Zolfigol, Mohammad Ali,Bamoniri, Abdolhamid
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- Facile Synthesis of 1,1-Diacetates from Aldehydes Using Montmorillonite K-10 Clay under Microwave Irradiation
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Selective and easy synthesis of acylals in dry media using montmorillonite K-10 clay in an Erlenmeyer flask under microwave activation in remarkably reduced reaction time is described.
- Karmakar, Dipankar,Prajapati, Dipak,Sandhu, Jagir S.
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- Application of poly(Vinylbenzyltrimethylammonium tribromide) resin as an efficient polymeric catalyst in the acetalization and diacetylation of benzaldehydes
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The applications of a new supported tribromide reagent (poly(vinylbenzyltrimethylammonium tribromide) resin) were reported. This supported tribromide resin was used as a catalyst in the acetalization and diacetylation of benzaldehydes under mild conditions with high efficiency. The effects of solvents, and amount of the supported tribromide resin on the reactions were investigated. Under the optimal conditions, most of acetal and 1,1-diacetates of benzaldehydes were selectively obtained in excellent yields.
- Han, Bingbing,Hu, Junjun,Li, Xianwei,Zheng, Zubiao
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supporting information
p. 287 - 293
(2021/04/28)
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- The studies on chemoselective promiscuous activity of hydrolases on acylals transformations
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Chemoselective, mild and convenient protocol for the hydrolysis of the synthetically relevant acylals via promiscuous enzyme-catalyzed hydrolysis has been developed. It has been shown that promiscuous activity of the used hydrolases dominates their native activity related with carboxylic esters hydrolysis. The main advantage of the present methodology is that it can be conducted under neutral conditions at room temperature. Moreover, complete deprotection of acylals takes place within 10–20 min. Developed protocol can be used with compounds having a variety of hydrolytic labile groups since the cleavage is proceeded under neutral conditions and occurs exclusively on acylal moiety. Further this protocol was extended by the tandem Passerini multicomponent reaction leading to the α-acetoxy amides using acylals as the surrogates of the carbonyl components to P-MCR.
- Koszelewski, Dominik,Ostaszewski, Ryszard
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- Chemoselective synthesis of 1,1-diacetates under solvent-free condition using efficient heterogeneous ecofriendly catalyst: P2O5/kaolin
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An efficient and chemoselective method for the preparation of acylals from different aldehydes and acetic anhydride using.....kaolin supported catalyst (P2O5). under solvent-free conditions is described herein. The present protocol offers several advantages including use of inexpensive and non-toxic catalyst support i.e., natural kaolin. Preparation of the supported catalyst is easy, the process is simple in operation, maintaining solvent free conditions, with short reaction times, high yields and affording selective protection of aldehyde in presence of ketone.
- Rai, Nityanand,Sharma, Abha
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p. 340 - 344
(2019/05/21)
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- N-Propylsulfamic acid supported onto magnetic Fe3O4 nanoparticles (MNPs-PSA) as a green and reusable heterogeneous nanocatalyst for the chemoselective preparation and deprotection of acylals
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Abstract: N-propylsulfamic acid supported onto magnetic Fe3O4 nanoparticles (MNPs-PSA) was simply synthesized and used as a highly efficient, environmentally friendly, and chemoselective catalyst for the synthesis of 1,1-diacetates (acylals) from the one-pot condensation reaction of various aromatic aldehydes with acetic anhydride, in high yield of products (86–96%) and short reaction time (20–60?min) under solvent-free conditions at room temperature. In addition to these results, we further studied the possibility of deprotection of the resulting acylals into benzaldehyde derivatives in this catalytic system by the addition of water. More importantly, noteworthy advantages of this study are non-use of toxic organic solvents and catalysts, simple work-up procedure, short reaction time, high yield of products, and recovery and reusability of MNPs-PSA by an external magnet. Graphical Abstract: A simple and highly efficient procedure for the protection of various aldehydes with acetic anhydride in the presence of N-propylsulfamic acid supported onto magnetic Fe3O4 nanoparticles (MNPs-PSA) is reported. We further studied the possibility of deprotection of the resulting acylals into benzaldehyde derivatives in this catalytic system by the addition of water as a green solvent. The catalyst was reused several times without loss of its catalytic activity.
- Sajjadifar, Sami,Nasri, Parastoo
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p. 6677 - 6689
(2017/10/06)
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- Microwave-assisted green synthesis of 1,1-diacetates (acylals) using selectfluor as an environmental-friendly catalyst under solvent-free conditions
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An efficient and simple procedure has been developed for the acetylation of aldehyde by selectfluor [1-(chloromethyl)-4-fluoro-1,4-diazoniabicyclo[2,2,2]octane bis(tetrafluoroborate)] as a chemoselective and environmentally friendly catalyst under solvent-free conditions or microwave irradiation. The application of microwave irradiation improved the yields and reduced the reaction times. In this study, selective conversion of aldehydes was observed in the presence of ketones, and the deprotection of 1,1-diacetates has also been achieved using selectfluor in water as green solvent in reflux conditions. The methodology provides synergy of microwave irradiation which offers several advantages such the simple work-up procedure, short reaction time, excellent yields and environmentally benign procedure.
- Rezayati, Sobhan,Hajinasiri, Rahimeh,Erfani, Zahra
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p. 2567 - 2576
(2016/03/16)
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- Synthesis of 1,1-diacetates catalyzed by cellulose sulfonic acid from aldehydes and acetic anhydride
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1,1-Diacetates have been synthesized in good to excellent yields via a reaction of corresponding aldehydes and acetic anhydride in the presence of cellulose sulfonic acid as a heterogeneous catalyst at room temperature. The protection of aldehydes generated an anhydrodimer as single product under similar reaction conditions. The catalysis is equally applicable for the deprotection of acylal in acetonitrile.
- Ding, Songsong,Zhang, Jiming,Shi, Wei,Zhou, Jianhua
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p. 340 - 342
(2015/02/19)
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- Preparation of 1,1-diacetates from aldehydes by LiBH4 and Ac2O in the presence of cation exchange resin
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A variety of 1,1-diacetates have been produced from the corresponding aldehydes (1 mmol) by LiBH4(1.25 mmol) and Ac2O (1 mL) in the presence of DOWEX(R)50WX4 (0.5 g) as a cation exchange resinwithin 10 min at room temperature with excellent yields of the products (93-97%).
- Rezaeekhordehforosh, Reza,Khezri, Behrooz,Setamdideh, Davood
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p. 1205 - 1209
(2015/10/28)
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- Solvent-free Chemoselective Synthesis of 1,1-diacetates Catalyzed by Iron Zirconium Phosphate
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In the present study, a mild, rapid, and efficient method for the protection of aldehydes with acetic anhydride (AA) in the presence of iron zirconium phosphate (ZPFe), at room temperature is reported. Selective conversion of aldehydes was observed in the presence of ketones. Under these conditions, different aldehydes bearing electron-withdrawing and electron-donating substituents were reacted with AA and the corresponding 1,1-diacetates (acylals) were obtained in high to excellent yields. The steric and electronic properties of the different substrates had a significant influence on the reaction conditions. Also, the deprotection of 1,1-diacetates has been achieved using this catalyst in water. The catalyst was characterized by several physico-chemical techniques. It was recovered easily from the reaction mixture, regenerated, and reused at least 7 times without significant loss in catalytic activity. This protocol has the advantages of easy availability, stability, reusability of the eco-friendly catalyst, chemoselectivity, simple experimental and work-up procedure, solvent-free conditions and only a stoichiometric amount of AA is needed.
- Karimi, Hirbod
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p. 1000 - 1010
(2015/12/01)
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- Zinc zirconium phosphate as an efficient catalyst for chemoselective synthesis of 1,1-diacetates under solvent-free conditions
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In the present study, a mild, rapid, and efficient method for the protection of aldehydes with acetic anhydride (AA) in the presence of zinc zirconium phosphate (ZPZn) as a nano catalyst, at room temperature is reported. Selective conversion of aldehydes was observed in the presence of ketones. Under these conditions, different aldehydes bearing electron-withdrawing and electron-donating substituents were reacted with AA and the corresponding 1,1-diacetates (acylals) were obtained in high to excellent yields. The steric and electronic properties of the different substrates had a significant influence on the reaction conditions. Also, the deprotection of 1,1-diacetates has been achieved using this catalyst in water. This nanocatalyst was characterized by several physico-chemical techniques. It was recovered easily from the reaction mixture, regenerated and reused at least 7 times without significant loss in catalytic activity. This protocol has the advantages of easy availability, stability, reusability of the eco-friendliness, chemoselectivity, simple experimental and work-up procedure, solvent-free conditions and usage of only a stoichiometric amount of AA.
- Hajipour, Abdol R,Karimi, Hirbod
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p. 1945 - 1955
(2015/12/30)
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- Poly(4-vinylpyridinium) perchlorate as an efficient solid acid catalyst for the chemoselective preparation of 1,1-diacetates from aldehydes under solvent-free conditions
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Poly(4-vinylpyridinium) perchlorate has been used as a supported, recyclable, environmentally-benign catalyst for the formation of acylals from aliphatic and aromatic aldehydes in good to excellent yields under solvent-free conditions. Notably, the reaction conditions were tolerant of ketones. This methodology offers several distinct advantages, including its operational simplicity and high product yield, as well as being green in terms of avoiding the use of toxic catalysts and solvents. Furthermore, the catalyst can be recovered and reused several times without any loss in its activity.
- Khaligh, Nader Ghaffari
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p. 329 - 334
(2014/04/03)
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- NaBH4/Ac2O/DOWEX(R)50WX4: A convenient system for fast preparation of gem-diacetates from aldehydes
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Reductive-acylalation of aldehydes has been carried out by NaBH 4/Ac2O/DOWEX(R)50WX4 system. A variety of aldehydes (1 mmol) have been reacted with Ac2O (0.5 mL) and NaBH4 (1 mmol) in the presence of DOWEX(R)50WX4 (0.5 g) for the preparation of their corresponding acylals within 1 min at room temperature with excellent yields of the products (90-95%). Ketones do not react with this system.
- Asl, Parisa Azizi,Setamdideh, Davood
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p. 940 - 944
(2014/10/16)
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- Functionalized Poly(Amidoamine) Dendrimer as a Strong Ionic Br?nsted Acid Organocatalyst for Protection/Deprotection of Aldehydes
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Poly(amidoamine) dendrimer (PAMAM) was successfully functionalized by chlorosulfonic acid to form an strong ionic acid catalyst. The resulting polymeric catalyst was shown to be an efficient catalyst for the synthesis of 1,1-diacetyl from aldehydes under free solvent conditions at room temperature. Also, the deprotection of the resulting aldehydes was investigated under catalytic conditions. The Hammett acidity function of catalyst showed that catalyst is a strong Br?nsted acid. Due to the multi-functional nature of PAMAM, the catalyst has high loading level of acidic protons.
- Pourjavadi, Ali,Hosseini, Seyed Hassan
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p. 1794 - 1801
(2015/10/29)
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- P4VP-H2SO4-catalyzed chemoselective protection of aldehydes to acylal along with deprotection reactions
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Poly(4-vinylpyridine)-supported sulfuric acid is an excellent reusable heterogeneous catalyst for the chemoselective synthesis of 1,1- diacetates(acylal) from aldehydes in dichloromethane at room temperature within a few minutes. The protection of salicyaldehyde generated an anhydro-dimer as single product under similar reaction conditions. The catalyst is equally applicable for the deprotection of acylal in acetonitrile. The catalyst was prepared by the wet impregnation technique.
- Dutta, Papia,Sarma, Parishmita,Borah, Ruli
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p. 1378 - 1386
(2013/05/09)
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- Ultrasound assisted the chemoselective 1,1-diacetate protection and deprotection of aldehydes catalyzed by poly(4-vinylpyridinium)hydrogen sulfate salt as a eco-benign, efficient and reusable solid acid catalyst
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Poly(4-vinylpyridinium) hydrogen sulfate solid acid was found to be efficient catalyst for preparation of 1,1-diacetate using ultrasound irradiation at ambient temperature and neat condition. Deprotection of the resulting 1,1-diacetates were achieved using the same catalyst in methanol solvent under ultrasound irradiation at room temperature. This new method consistently has the advantage of excellent yields and short reaction times. Utilization of solvent free, simple reaction conditions, isolation, and purification makes this manipulation very interesting from an economic and environmental perspective. Further, the catalyst can be reused and recovered for several times.
- Khaligh, Nader Ghaffari,Shirini, Farhad
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- Sulfonated rice husk ash (RHA-SO3H): A highly powerful and efficient solid acid catalyst for the chemoselective preparation and deprotection of 1,1-diacetates
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Rice husk ash (RHA), as a source of amorphous silica, was treated with chlorosulfonic acid and sulfonated rice husk ash (RHA-SO3H) as a highly powerful solid acid catalyst was obtained and characterized with a variety of techniques including IR, TGA, SEM, XRD, pH analysis, Hammett acidity function and BET method. This solid acid showed excellent catalytic activity for the protection and deprotection of aldehydes with Ac2O at room temperature under solvent free conditions. The procedure gave the products in excellent yields in very short reaction times and good to high yields. Also this catalyst can be reused for several times without loss of its catalytic activity.
- Shirini, Farhad,Mamaghani, Manouchehr,Seddighi, Mohadeseh
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- Polystyrene-supported TiCl4 as a novel, efficient and reusable polymeric Lewis acid catalyst for the chemoselective synthesis and deprotection of 1,1-diacetates under eco-friendly conditions
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Copolymer beads of styrene and divinylbenzene (5-7%) were synthesized and combined with titanium tetrachloride in CS2 to form a stable complex. The PS/TiCl4 complex was used as a mild and efficient polymer-supported Lewis acid catalyst for the preparation of 1,1-diacetates from various types of aldehydes under heterogeneous conditions at room temperature. Deprotection of the resulting 1,1-diacetates has also been achieved using the same catalyst in methanol. This new protocol has the advantages of easy availability, stability, reusability of the eco-friendly catalyst, high to excellent yields, chemoselectivity, simple experimental and work-up procedure. Moreover, this polymeric catalyst could be recovered easily and reused several times without significant loss in activity.
- Rahmatpour, Ali,Mohammadian, Sara
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p. 912 - 919
(2013/10/22)
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- Ultrasound-assisted synthesis of acylals catalyzed by stannum (IV) phosphomolybdate under solvent-free condition
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An efficient method for the synthesis of acylals from different aldehydes and acetic anhydride in the presence of Keggin-type stannum (IV) phosphomolybdate under ultrasound irradiation at room temperature was achieved. This method provides a new and efficient protocol in terms of cost effective of catalyst, a wide scope of substrates, and simple work-up procedure.
- Ai, Hong Mei,Liu, Qing
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experimental part
p. 299 - 301
(2012/07/17)
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- Iron(III) tosylate catalyzed acylation of alcohols, phenols, and aldehydes
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Iron(III) p-toluenesulfonate (tosylate) is an efficient catalyst for acetylation of alcohols, phenols, and aldehydes. The acetylation of 1° and 2° alcohols, diols, and phenols proceeded smoothly with 2.0 mol % of catalyst. However, the reaction worked well with only a few 3° alcohols. The methodology was also applicable to the synthesis of a few benzoate esters but required the use of 5.0 mol % catalyst. Aldehydes could also be converted into the corresponding 1,1-diesters (acylals) under the reaction conditions. Iron(III) tosylate is an inexpensive, and easy to handle, commercially available catalyst.
- Baldwin, Neil J.,Nord, Anna N.,O'Donnell, Brendan D.,Mohan, Ram S.
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p. 6946 - 6949
(2013/01/15)
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- Introduction of N-sulfonic acid poly(4-vinylpyridinum) chloride as an efficient and reusable catalyst for the chemoselective 1,1-diacetate protection and deprotection of aldehydes
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N-sulfonic acid poly(4-vinylpyridinium) chloride is easily prepared by the reaction of poly(4-vinylpyridine) with neat chlorosulfonic acid. This reagent can be used as an efficient catalyst for the preparation of 1,1-diacetates at room temperature and neat condition. Deprotection of the resulting 1,1-diacetates can also be achieved using the same catalyst in methanol. This new method consistently has the advantages of excellent yields and short reaction times. Further, the catalyst can be reused and recovered for several times.
- Shirini, Farhad,Jolodar, Omid Goli
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experimental part
p. 61 - 69
(2012/04/17)
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- Schiff base complex of metal ions supported on superparamagnetic Fe 3O4@SiO2 nanoparticles: An efficient, selective and recyclable catalyst for synthesis of 1,1-diacetates from aldehydes under solvent-free conditions
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We report a new multistep method for preparing functionalized superparamagnetic Fe3O4@SiO2 possessing high saturation magnetization. During the first step, Fe3O 4@SiO2 nanosphere core-shell is synthesized using nano-Fe3O4 as the core, TEOS as the silica source and PVA as the surfactant. Then, Schiff base complex of metal is synthesized from the reaction between Schiff base and metal acetates [Co(OAc)2, Mn(OAc)2, Ni(OAc)2, Cu(OAc)2, Hg(OAc) 2, Cr(OAc)3 and Cd(OAc)2] on the Fe 3O4@SiO2 surface. The structural and magnetic properties of functionalized magnetic silica are identified by transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) instruments. Moreover, functionalized Fe3O4@SiO2 possessed a superparamagnetic characteristic with saturation magnetization value of about 34 emu/g. NMR, FT-IR, elemental analysis and XRD were also used for the identification of these structures. The catalytic ability of Fe 3O4@SiO2/Schiff base complex of metal ions was found to be an efficient nanocatalyst for the conversion of aldehydes to their corresponding 1,1-diacetates compounds under mild and solvent-free conditions at room temperature. This method gives notable advantages such as excellent chemoselectivity, mild reaction condition, short reaction times and excellent yields. Also, the aforementioned nanocatalyst can be easily recovered by a magnetic field and reused for subsequent reactions for at least 5 times without noticeable deterioration in catalytic activity.
- Esmaeilpour, Mohsen,Sardarian, Ali Reza,Javidi, Jaber
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p. 359 - 367
(2013/02/21)
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- A highly efficient solvent-free acetalization of aldehydes to 1,1-diacetates catalyzed by SiO2-Pr-SO3H
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1,1-Diacetates are prepared in excellent yields from aldehydes and acetic anhydride under solvent-free conditions at room temperature in short reaction times using catalytic amount of sulfonic acid functionalized silica (SiO 2-Pr-SO3H) which could be easily handled and removed from the mixture of reaction.
- Ziarani, Ghodsi Mohammadi,Badiei, Alireza,Shahjafari, Fatemeh,Pourjafar, Taiiebeh
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experimental part
p. 10 - 13
(2012/05/19)
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- Rice husk supported FeCl3 nanoparticles as an efficient and reusable catalyst for the chemoselective 1,1-diacetate protection and deprotection of aldehydes
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1,1-Diacetates were produced from a variety of aromatic aldehydes using rice husk supported FeCl3 nanoparticles as a catalyst. The procedure generally resulted in good yields (98%) of aromatic aldehydes including those carrying electron donating- or withdrawing-substituents. Deprotection of the resulting 1,1-diacetates was also achieved using the same catalyst in ethanol. This new method consistently has the advantages of excellent yields and relatively short reaction times. Further, the catalyst can be reused and recovered for several times.
- Shirini, Farhad,Akbari-Dadamahaleh, Somayeh,Mohammad-Khah, Ali
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- An efficient method for the transthioacetalization of acylals and acetals under mild conditions
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A rapid and efficient method for the transthioacetalization of acylals (1,1-diacetates) and acyclic and cyclic acetals is described. The reaction was carried out using 1-benzyl-4-aza-1-azoniabicyclo[2.2.2]octane tribromide (1 mol%). The yield of the transthioacetalization was high and reaction conditions involve the use of acetonitrile as the solvent at room temperature; isolation is simple and the products are nearly pure.
- Pourmousavi, Seied Ali,Hadavankhani, Majid,Zinati, Zahra
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experimental part
p. S495-S501
(2012/05/31)
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- Amorphous carbon-silica composites bearing sulfonic acid as solid acid catalysts for the chemoselective protection of aldehydes as 1,1-diacetates and for N-, O- and S-acylations
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Amorphous carbon-silica composites bearing sulfonic acid derived from inexpensive natural organic compounds (glucose, maltose, cellulose, chitosan and starch) were prepared by partial carbonization followed by sulfonation and their catalytic activity was evaluated for the protection of aldehydes as 1,1-diacetates and for N-, O- and S-acylations under solvent-free conditions. Different biomaterials have been chosen, with a view to select the most active solid acid catalyst. Carbon-silica composites were characterized by FTIR, XRD and elemental analysis. Sulfonated carbon-silica composite derived from starch was found to be the most active and could be recycled for several runs without loss of significant activity. It was also characterized by TGA, SEM and TEM.
- Gupta, Princy,Paul, Satya
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experimental part
p. 2365 - 2372
(2011/10/31)
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- Chromic(III) sulfamate as a versatile catalyst for organic synthesis
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Chromic sulfamate was synthesized and used as catalyst for the first time in various organic reactions such as the transformation of aldehydes or ketones and indole to bis(indolyl)methanes, the transformation of aldehydes and acetic anhydride to 1,1-diacetates and Biginelli reaction. The advantages of the chromic sulfamate are ease of preparation, easy handling, simple work-up and versatility.
- Liu, Qing,Li, Zhen
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experimental part
p. 3208 - 3210
(2012/02/03)
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- Preparation of silica-bonded propyl-diethylene-triamine-N-sulfamic acid as a recyclable catalyst for chemoselective synthesis of 1,1-diacetates
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A simple and efficient procedure for the preparation of silica-bonded propyl-diethylene-triamine-N-sulfamic acid (SPDTSA) by reaction of 3-diethylenetriamine-propylsilica (DTPS) and chlorosulfonic acid in chloroform is described. Silica-bonded propyl-diethylene-triamine-N-sulfamic acid is employed as a recyclable catalyst for the synthesis of 1,1-diacetates from aromatic aldehydes and acetic anhydride under mild and solvent-free conditions at room temperature. Catalyst could be recycled for several times without any additional treatment.
- Nouri Sefat, Maryam,Deris, Abdolah,Niknam, Khodabakhsh
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experimental part
p. 2361 - 2367
(2012/02/03)
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- A new and efficient procedure for the production of 1,1-diacetate from corresponding aldehydes promoted by silica chromate (SiO2-O-CrO 2-O-SiO2)
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Chemical Equation Presented A wide range of aromatic aldehydes has been selectively converted to 1,1-diacetates using silica chromate (SiO 2-O-CrO2-O-SiO2) under solvent-free conditions at room temperature in moderate to good yields. This protocol is mild and efficient compared to other reported methods. Copyright Taylor & Francis Group, LLC.
- Bamoniri, Abdolhamid,Ghorbani-Choghamarani, Arash,Mirjalili, Bi Bi Fatemeh
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experimental part
p. 381 - 388
(2011/04/22)
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- Mild and chemoselective synthesis and deprotection of geminal diacetates catalyzed by titanium(IV) halides
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A novel, mild, and chemoselective method was developed for the preparation of gem-diacetates from aldehydes and acetic anhydride in the presence of titanium(IV) fluoride (1-5 mol%) under solvent-free conditions at room temperature. The reaction showed a high chemoselectivity toward aldehydes in the presence of ketones. Moreover, titanium(IV) fluoride also catalyzed the deprotection of gem-diacetates to the corresponding aldehydes in water. This efficient and simple method has several benefits, including the use of an inexpensive catalyst, solvent-free conditions, mild reaction temperatures, and high yields, which make it both cost-effective and environmentally friendly. Georg Thieme Verlag Stuttgart.
- Jung, Misuk,Yoon, Jieun,Kim, Hak Sung,Ryu, Jae-Sang
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experimental part
p. 2713 - 2720
(2010/10/02)
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- An efficient and chemoselective procedure for acylal synthesis
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A novel heterogeneous efficient procedure has been developed for the chemoselective synthesis of acylals (1,1-diacetates) under solvent-free conditions. A novel catalyst prepared by the sulfuric acid catalyzed copolymerization of p-toluenesulfonic acid and paraformaldehyde displays extremely high activities for the title reactions, affording average yields over 90% within several minutes. A comparative study showed that the novel catalyst has much higher activity than other catalysts used for this purpose. Besides, the novel catalyst displays chemoselectivity for the protection of aldehydes in the presence of ketones. In addition the high acidity (4.0 mmol/g), thermal stability (200 °C) and easy reusability make the novel catalyst one of the best choices for the process.
- Fan, Da-He,Wang, Hui,Mao, Xing-Xing,Shen, Yong-Miao
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experimental part
p. 6493 - 6501
(2010/11/04)
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- Chemoselective synthesis of 1,1-diacetates from aldehydes using anhydrous cobalt(II) bromide under solvent-free conditions
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A mild and efficient method has been developed for the chemoselective preparation of 1,1-diacetates (acylals) from aldehydes catalyzed in the presence of a catalytic amount (0.1mmol) of anhydrous cobalt(II) bromide under solvent-free conditions. The remarkable selectivity under mild and neutral conditions, excellent yields, short reaction time, and easily available and inexpensive catalyst are important features of this method.
- Meshram, Gangadhar A.,Patil, Vishvanath D.
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experimental part
p. 442 - 449
(2010/04/02)
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- An efficient and green procedure for the preparation of acylals from aldehydes catalyzed by alum [KAl(SO4)212H2O]
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Alum [KAl(SO4)2-12H2O] is an inexpensive, efficient, non-toxic and mild catalyst for the preparation of acylals from aromatic and heteroaryl aldehydes with acetic anhydride at room temperature under solvent-free conditions
- Shelke, Kiran,Sapkal, Suryakant,Kategaonkar, Amol,Shingate, Bapurao,Shingare, Murlidhar S.
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experimental part
p. 109 - 112
(2010/08/06)
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- Chloroferrate(III) ionic liquid as recyclable catalyst for the acetylation of alcohols and phenols and for 1,1-Diacylation of aldehydes
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A Lewis acidic ionic liquid, [bmim][FeCl4], was employed to catalyze acetylation of alcohols and phenols, and the conversion of aldehydes to corresponding 1,1-diacetates without conventional organic solvents. The catalyst is easily available, water-tolerant, recoverable and easy to handle.
- Wanga, Dong-Sheng,Lib, Gui-Yun,Pengb, Yan-Qing
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experimental part
p. 834 - 838
(2010/08/13)
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