- A Method For Preparing (Meth)Acrylic Acid Ester Based Compound
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The invention relates to a method for preparing a (meth)acrylic acid ester-based compound, and according to the preparation method, a (meth)acrylic acid ester-based compound can be prepared with high purity and high yield, by easily introducing an acrylic structure into alcohol using a diamine-based compound and acid anhydride.
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Paragraph 0071-0072
(2021/05/07)
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- Synthesis, Characterisation, and Determination of Physical Properties of New Two-Protonic Acid Ionic Liquid and its Catalytic Application in the Esterification
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A new ionic liquid was synthesised, and its chemical structure was elucidated by FT-IR, 1D NMR, 2D NMR, and mass analyses. Some physical properties, thermal behaviour, and thermal stability of this ionic liquid were investigated. The formation of a two-protonic acid salt namely 4,4′-trimethylene-N,N′-dipiperidinium sulfate instead of 4,4′-trimethylene-N,N′-dipiperidinium hydrogensulfate was evidenced by NMR analyses. The catalytic activity of this ionic liquid was demonstrated in the esterification reaction of n-butanol and glacial acetic acid under different conditions. The desired acetate was obtained in 62-88 % yield without using a Dean-Stark apparatus under optimal conditions of 10 mol-% of the ionic liquid, an alcohol to glacial acetic acid mole ratio of 1.3: 1.0, a temperature of 75-100°C, and a reaction time of 4 h. α-Tocopherol (α-TCP), a highly efficient form of vitamin E, was also treated with glacial acetic acid in the presence of the ionic liquid, and O-acetyl-α-tocopherol (Ac-TCP) was obtained in 88.4 % yield. The separation of esters was conducted during workup without the utilisation of high-cost column chromatography. The residue and ionic liquid were used in subsequent runs after the extraction of desired products. The ionic liquid exhibited high catalytic activity even after five runs with no significant change in its chemical structure and catalytic efficiency.
- Shahnavaz, Zohreh,Zaharani, Lia,Khaligh, Nader Ghaffari,Mihankhah, Taraneh,Johan, Mohd Rafie
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p. 165 - 172
(2020/10/26)
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- Continuous-Flow Chemo and Enzymatic Synthesis of Monoterpenic Esters with Integrated Purification
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Monoterpenic esters are very important flavor and fragrance compounds due to their organoleptic properties. Despite their importance, many drawbacks are found for the production of monoterpenic esters. Here in we report two different approach's (chemo and enzymatic) for the continuous production of monoterpenic esters with integrated purification arriving on the desired molecules with high yields (>95%) and short reaction times.
- Adarme, Carlos A.A.,Le?o, Raquel A.C.,de Souza, Stefania P.,Itabaiana, Ivaldo,de Souza, Rodrigo O.M.A.,Rezende, Claudia M.
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- Production of l-menthyl acetate through kinetic resolution by?Candida cylindracea lipase: effects of alkaloids as additives
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Abstract: Enzymatic transesterification of dl-menthol with vinyl acetate in tert-Butyl methyl ether (TBME) catalyzed by Candida cylindracea lipase (CCL) was carried out in the presence of cinchona alkaloid as additive. The effects of various reaction parameters, such as lipase nature and loading, acylating agent, molecular sieves, solvents and various additives, on the reactivity as well as on the enantioselectivity were investigated. A significant improvement of CCL reactivity has been recorded after using cinchona alkaloid as additive in TBME. A high enantiomeric ratio (E = 80) was achieved when 30?mol% of quinidine was added, and l-(-)-menthyl acetate was obtained with 93% optical purity and 49% conversion. This process was easily applied to gram-scale quantities, using commercially inexpensive lipase, providing high yield optically active menthol under mild experimental conditions. Graphical abstract: [Figure not available: see fulltext.].
- Belkacemi, Fatima Zohra,Merabet-Khelassi, Mounia,Aribi-Zouioueche, Louisa,Riant, Olivier
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p. 6847 - 6860
(2018/07/15)
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- Proton-gradient-transfer acid complexes and their catalytic performance for the synthesis of geranyl acetate
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Special proton-gradient-transfer acid complexes (PGTACs) in which the bonded protons are not equivalent and have gradients in transfer ability, acidity, and reactivity were reported. The acidity gradient of the protons gave the PGTACs excellent catalytic activity and selectivity in the esterification of terpenols. These PGTACs are “reaction-induced self-separation catalysts” and can be easily reused. The kinetics with PGTACs as catalyst in the esterification of geraniol were also studied for use in engineering design.
- Chen, Yongle,Ding, Shiya,Zheng, Wentao,Zhang, Yiyang,Wu, Youting,Hu, Xingbang
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p. 2114 - 2121
(2017/01/16)
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- P4VPy–CuO nanoparticles as a novel and reusable catalyst: application at the protection of alcohols, phenols and amines
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P4VPy–CuO nanoparticles were synthesized using ultrasound irradiations. Relevant properties of the synthesized nanoparticles were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. After identification, the prepared reagent was used for the promotion of different types of protection reactions of alcohols, phenols and amines. Easy workup, short reaction times, excellent yields, relatively low cost and reusability of the catalyst are the striking features of the reported methods.
- Shirini, Farhad,Fallah-Shojaei, Abdollah,Abedini, Masoumeh,Samavi, Laleh
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p. 1699 - 1712
(2016/07/27)
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- Heteropoly acid catalysts for the synthesis of fragrance compounds from bio-renewables: Acetylation of nopol and terpenic alcohols
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The cesium salt of tungstophosphoric heteropoly acid, Cs2.5H0.5PW12O40, is an active and environmentally friendly heterogeneous catalyst for the liquid-phase acetylation of nopol and several biomass-derived terpenic alcohols (i.e., α-terpineol, nerol, geraniol, linalool, menthol, isoborneol, perillyl alcohol, carveol, isopulegol, carvacrol and nerolidol) with acetic anhydride. The resulting flavor and fragrance acetic esters, which are widely used in perfumery, household and food products, are obtained in good to excellent yields. The reactions occur at room temperature with low catalyst loadings without substantial catalyst leaching and can be performed with stoichiometric amounts of an acetylating agent in solvent free systems.
- Costa, Vinicius V.,Da Silva Rocha, Kelly A.,Oliveira, Luiz C. A.,Kozhevnikova, Elena F.,Kozhevnikov, Ivan V.,Gusevskaya, Elena V.
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p. 43217 - 43222
(2016/05/24)
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- DMAP-based flexible polymer networks formed via Heck coupling as efficient heterogeneous organocatalysts
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Two DMAP-based flexible polymer networks TPB-DMAP and TPA-DMAP have been successfully synthesized via palladium catalyzed Heck cross-coupling. The structures of these polymers were confirmed by solid state 13C CP/MAS and Fourier transform infrared spectroscopy (FTIR). Although both polymers have negligible surface areas, they exhibit excellent catalytic efficiency for the acylation of 1-phenylethanol with acetic anhydride due to their good swelling capacities. Utilized as a typical catalyst, the polymer TPA-DMAP shows high activities for acylation of a variety of alcohols to the corresponding esters. Moreover, the catalyst can be recycled at least ten times without obvious loss of catalytic activity.
- Xu, Wei,Xia, Wu,Guan, Yukun,Wang, Yiming,Lu, Cuifen,Yang, Guichun,Nie, Junqi,Chen, Zuxing
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- Efficient approach for the chemoselective acetylation of alcohols catalyzed by a novel metal oxide nanocatalyst CuO-ZnO
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A new method has been developed for the chemoselective acetylation of alcohols with acetic anhydride in the presence of phenols using a novel, recyclable CuO-ZnO nanocatalyst. The catalyst was synthesized using the co-precipitation method and characterized by N2 adsorption-desorption, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersion scanning analyses. Furthermore, this catalyst could be recycled up to six times without significant loss in its activity.
- Albadi, Jalal,Alihosseinzadeh, Amir,Mardani, Mehdi
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p. 308 - 313
(2015/09/28)
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- Synthesis of lipase nano-bio-conjugates as an efficient biocatalyst: Characterization and activity-stability studies with potential biocatalytic applications
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In the present study, we have synthesized lipase-nano-bio-conjugates via immobilization of various lipases on multiwall carbon nano-tubes (MCNT), in order to construct an efficient and recyclable biocatalytic system. In a screening study lipase Pseudomonas fluorescens (PFL) acted as an efficient biocatalyst (lipase-nano-bio-conjugates) which showed higher retention of lipase activity and protein loading. Consequently the immobilization support : lipase (MCNT : PFL) composition was screened in which MCNT : PFL (2 : 1) was calculated as a robust biocatalyst composition which showed higher activity retention and protein loading. This nano-bio-conjugate was then characterized in detail with physical and biochemical techniques using SEM, TEM, FTIR, Km, Vmax, catalytic efficiency and (%) water content analysis. This developed biocatalyst was further used for practical biocatalytic applications such as O-acylation reactions. Various reaction parameters were optimized in detail like reactant molar ratio (2 : 3.5), solvent, MCNT : PFL biocatalyst amount (36 mg), temperature (50°C) etc. The developed biocatalytic protocol was then extended to synthesize several (twenty-two) industrially important acylated moieties with an excellent yield, these products are well characterized by 1HNMR, 13CNMR and GCMS analysis. Moreover in the present study, we have reviewed the potential industrial applications of various synthesized compounds. Also, we have studied the thermodynamic aspect which demonstrated more feasibility of use of immobilized MCNT : PFL lipase over free lipase. Interestingly, immobilized MCNT : PFL lipase showed 2.3 fold higher catalytic activity than free PFL. Besides this, the biocatalyst was efficiently recycled for up to five cycles. Thus the present protocol demonstrated, (i) synthesis of nano-bio-conjugates as a bio-catalyst, (ii) detailed physical-biochemical characterization of nano-bio-conjugates, (iii) optimization of the biocatalytic protocol (iv) practical biocatalytic applications along with a mechanistic study (v) a thermodynamic feasibility study and (vi) recyclability study. 2015
- Badgujar, Kirtikumar Chandulal,Sasaki, Takehiko,Bhanage, Bhalchandra Mahadeo
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p. 55238 - 55251
(2015/07/07)
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- Microwave-Assisted Catalytic Acetylation of Alcohols by Gold-Nanoparticle-Supported Gadolinium Complex
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A gold nanoparticle (AuNP)-supported gadolinium complex (RS-Au-L-Gd) catalyst was prepared through simple chelation of GdCl3 to the surface-bound spacer, 1,4,7-tris(carboxymethyl)-10-(11-mercaptoundecyl)-1,4,7,10-tetraazacyclododecane (HSDO3A). This AuNP-supported Gd complex was found to be a highly effective catalyst for the acetylation of various alcohols and phenol in the presence of acetic anhydride. With a loading of 0.4 mol% of RS-Au-L-Gd, the almost complete transformation can be achieved in 60 s under microwave irradiation conditions. This hybrid catalyst was air stable, water soluble, dissolvable in many organic media, and precipitable. It can be readily recycled more than eight times without any significant loss of its catalytic activity. GRAPHICAL ABSTRACT.
- Chang, Tsao-Ching,Yu, Shuchun Joyce
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supporting information
p. 661 - 672
(2015/10/29)
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- Tribromoisocyanuric acid (TBCA) as a mild and metal free catalyst for the acetylation and formylation of hydroxyl groups under solvent free conditions
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A convenient approach for acetylation and formylation of various types of alcohols and phenols with acetic anhydride and formic acid in the presence of Tribromoisocyanuric acid (TBCA) as catalyst is reported. The reactions were carried out under solvent-free condition and in good to high yields at room temperature. This present method is featured with relatively mild reaction conditions, simple operation, broad substrate scope, clean work-up, short reaction times, good to high yields, excellent selectivity and also avoids tedious purifications and the use of toxic reagents.
- Hekmatian, Zahra,Khazaei, Ardeshir
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p. 1565 - 1570
(2016/01/26)
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- Synthesis, characterization and application of poly(N,N'-dibromo- Nethylnaphthyl-2,7-disulfonamide) as an efficient catalyst for the acetylation and deacetylation reactions
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In this work, a novel polymer namely poly(N,N'-dibromo-N-ethylnaphthyl-2,7- disulfonamide) (PBNS) is synthesized and characterized by studying its IR, 1H NMR, 13C NMR and thermal gravimetric analysis (TGA). This polymer is utilized as a highly efficient, heterogeneous and recyclable N-bromo reagent to catalyze acetylation of various compounds such as alcohols, phenols, thiol and amine with acetic anhydride under solvent-free conditions, and also it worthily catalyzes deacetylation of acetate esters in aqueous media.
- Khazaei, Ardeshir,Saednia, Shahnaz,Roshani, Liela,Kazem-Rostami, Masoud,Zare, Abdolkarim
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p. 159 - 167
(2014/05/20)
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- Rice husk ash: A new, cheap, efficient, and reusable reagent for the protection of alcohols, phenols, amines, and thiols
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Amild, efficient, and eco-friendly protocol for the protection of alcohols and phenols as trimethylsilyl ethers has been developed using rice husk ash as a reagent. This reagent is also able to catalyze the acetylation of alcohols, phenols, thiols, and amines with acetic anhydride. All reactions were performed under mild conditions in good to high yields. Copyright
- Shirini,Akbari-Dadamahaleh, Somayeh,Mohammad-Khah, Ali
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p. 577 - 586
(2014/06/09)
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- Novel hybrid materials on the basis of nanostructured tin dioxide and a lipase from Rhizopus delemar with improved enantioselectivity
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We obtained novel hybrid materials on the basis of covalently bounded to amino-grafted tin dioxide lipase from Rhizopus delemar (NH2-nano- SnO2-RhD). Under the optimal condition, the protein loading yielded of 14.7 mg/g NH2-nano-SnO2, while the adsorption capacity of the unmodified nano-SnO2 for the same enzyme was 38.5 mg/g. At the same time, NH2-nano-SnO2-RhD exhibited specific hydrolytic activity of 77.6 U/mg prot. which is 2.5-fold higher in comparison to that of the physically adsorbed on nano-SnO2 lipase (nano-SnO 2-RhD). In ten reaction cycles of tributyrin hydrolysis, up to 70% of the activity of NH2-nano-SnO2-RhD was preserved. Upon immobilization the enantioselectivity of the lipase for the reaction of acylation of (±)-menthol was improved. For the two biocatalysts, the highest yield of (-)-menthyl acetate (more than 35%) was obtained when glyceryl triacetate was used as acylating reagent, however, the enantiomeric excess was only 89.5% for the covalently bonded lipase and 85.0% for the physically adsorbed one. Higher enantiomeric excess was obtained when vinyl acetate was used as an acylating reagent; however, the conversion in that case did not exceed 20%. The addition of small amounts of pyrrolidinium-based ionic liquids, 1-methyl-1-octyl-pyrrolidinium bis(trifluoromethyl)sulfonyl imide [MOPyrro][NTf2], 1-methyl-1-octyl-pyrrolidinium hexafluorophosphate [MOPyrro][PF6], and 1-methyl-1-octyl-pyrrolidinium tetrafluoroborate [MOPyrro][BF4], to the reaction mixture resulted in decrease of (±) menthol conversion rate. All tested ionic liquids enhanced the enantioselectivity of nano-SnO2-RhD, and the best result was obtained in presence of [MOPyrro][PF6] (enantiomeric ratio >140).
- Guncheva, Maya,Dimitrov, Momtchil,Napoly, Francois,Draye, Micheline,Andrioletti, Bruno
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- Tris(pentafluorophenyl)borane catalyzed acylation of alcohols, phenols, amines, and thiophenols under solvent-free condition
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The acylation of alcohols, phenols, amines, and thiophenols was accomplished with 0.5 mol % of tris(pentafluorophenyl)borane [B(C 6F5)3] at ambient temperature under solvent-free condition. Major advantages of this method include high yield, short reaction time, simple procedure, compatibility with sensitive protecting groups as well as other functional groups, absence of racemization of optical active compounds, and epimerization of sugars.
- Prajapti, Santosh Kumar,Nagarsenkar, Atulya,Babu, Bathini Nagendra
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p. 1784 - 1787
(2014/03/21)
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- In situ generated acylimidazolium acetate as an efficient catalyst and acylating agent for the acetylation of alcohols, phenols, and amines at ambient temperature
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Acylimidazolium acetate was readily prepared in situ from the reaction of imidazole with acetic anhydride and subsequently acted as a catalyst and acylating agent for the efficient acetylation of alcohols, phenols, and amines at ambient temperature.
- Nowrouzi, Najmeh,Alizadeh, Seyedeh Zahra
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p. 1787 - 1790
(2013/10/21)
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- Solvent-free acetylation and tetrahydropyranylation of alcohols catalyzed by recyclable sulfonated ordered nanostructured carbon
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Rapid and practical green acetylation and tetrahydropyranylation routes of structurally diverse alcohols and phenols were applied under solvent-free reaction conditions providing excellent yields, using catalytic amounts of environmentally friendly sulfonated ordered nanoporous carbon (CMK-5-SO 3H). Non-toxic nature of the catalyst, its easy handling, recovery and reusability, and the absence of any solvent characterize the presented procedures as efficient methods. These procedures provide methods for the separation of the product by simple filtration.
- Zareyee, Daryoush,Alizadeh, Parastoo,Ghandali, Mohammad S.,Khalilzadeh, Mohammad A.
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p. 713 - 721
(2013/07/26)
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- Regioselective oxidation of nonactivated alkyl C-H groups using highly structured non-heme iron catalysts
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Selective oxidation of alkyl C-H groups constitutes one of the highest challenges in organic synthesis. In this work, we show that mononuclear iron coordination complexes Λ-[Fe(CF3SO3) 2((S,S,R)-MCPP)] (Λ-1P), Δ-[Fe(CF3SO 3)2((R,R,R)-MCPP)] (Δ-1P), Λ-[Fe(CF 3SO3)2((S,S,R)-BPBPP)] (Λ-2P), and Δ-[Fe(CF3SO3)2((R,R,R)-BPBPP)] (Δ-2P) catalyze the fast, efficient, and selective oxidation of nonactivated alkyl C-H groups employing H2O2 as terminal oxidant. These complexes are based on tetradentate N-based ligands and contain iron centers embedded in highly structured coordination sites defined by two bulky 4,5-pinenopyridine donor ligands, a chiral diamine ligand backbone, and chirality at the metal (Λ or Δ). X-ray diffraction analysis shows that in Λ-1P and Λ-2P the pinene rings create cavity-like structures that isolate the iron site. The efficiency and regioselectivity in catalytic C-H oxidation reactions of these structurally rich complexes has been compared with those of Λ-[Fe(CF3SO3) 2((S,S)-MCP)] (Λ-1), Λ-[Fe(CF3SO 3)2((S,S)-BPBP)] (Λ-2), Δ-[Fe(CF 3SO3)2((R,R)-BPBP)] (Δ-2), Λ-[Fe(CH3CN)2((S,S)-BPBP)](SbF6) 2 (Λ-2SbF6), and Δ-[Fe(CH3CN) 2((R,R)-BPBP)](SbF6)2 (Δ-2SbF 6), which lack the steric bulk introduced by the pinene rings. Cavity-containing complexes Λ-1P and Λ-2P exhibit enhanced activity in comparison with Δ-1P, Δ-2P, Λ-1, Λ-2, and Λ-2SbF6. The regioselectivity exhibited by catalysts Λ-1P, Λ-2P, Δ-1P, and Δ-2P in the C-H oxidation of simple organic molecules can be predicted on the basis of the innate properties of the distinct C-H groups of the substrate. However, in specific complex organic molecules where oxidation of multiple C-H sites is competitive, the highly elaborate structure of the catalysts allows modulation of C-H regioselectivity between the oxidation of tertiary and secondary C-H groups and also among multiple methylene sites, providing oxidation products in synthetically valuable yields. These selectivities complement those accomplished with structurally simpler oxidants, including non-heme iron catalysts Λ-2 and Λ-2SbF6.
- Gómez, Laura,Canta, Merceì,Font, David,Prat, Irene,Ribas, Xavi,Costas, Miquel
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p. 1421 - 1433
(2013/03/29)
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- Highly efficient solvent-free acetylation of alcohols with acetic anhydride catalyzed by recyclable sulfonic acid catalyst (SBA-15-Ph-Pr-SO3H)- An environmentally benign method
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The catalytic activity of highly thermal stable, hydrophobic, and complete heterogeneous propylsulfonic acid functionalized nanostructured SBA-15 for excellent acetylation of alcohols and phenols with acetic anhydride at ambient temperature in solvent-free conditions was examined under environmentally benign reaction conditions. The salient features of this protocol are the absence of solvent, a green experimental procedure, and simple reusability of the catalyst (at least five reaction cycles).
- Zareyee, Daryoush,Ghadikolaee, Abdollah Razaghi,Khalilzadeh, Mohammad A.
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experimental part
p. 464 - 468
(2012/06/16)
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- RECYCLABLE CATALYSTS FOR ESTERIFICATION OR ACYLATION OF ALCOHOLS
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A compound is useful as a recyclable catalyst for esterification or acylation of alcohols and consists of saccharine and a compound comprising a pyridine moiety. In addition, also a method of preparing the compound and an ester synthesis method using the compound are introduced.
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Page/Page column 3
(2012/07/28)
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- Preparation of SO42-/ Fe2O 3-TiO2-Nd2O3 solid acid and its activity for the synthesis of menthyl acetate
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This paper reports the preparation of SO42-/ Fe 2O3-TiO2-Nd2O3 (designated as SFTN) by combustion method, which were characterized by FT-IR and NH3-TPD techniques respectively. The results showed that SFTN kept the typical covalence S=O bond structure of SO42-/MxO y(SM) solid acids, and both Lewis and Bronsted acid sites existed; SFTN exhibited higher activity for the esterification of acetic acid and menthol, with 98.30% yield of menthyl acetate. The higher activity was attribute to the enhancement of acidic properties of the catalyst by the addition of Nd2O3 to SO42-/Fe2O 3-TiO2 (SFT).
- Yang, Chunhua,Fan, Meiqing,Chen, Gang,Zhang, Long
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experimental part
p. 72 - 75
(2012/05/07)
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- 4-(N,N-dimethylamino)pyridine-embedded nanoporous conjugated polymer as a highly active heterogeneous organocatalyst
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We report herein for the first time the incorporation of a versatile organocatalyst, 4-(N,N-dimethylamino)pyridine (DMAP), into the network of a nanoporous conjugated polymer (NCP) by the "bottom-up" approach. The resulting DMAP-NCP material possesses highly concentrated and homogeneously distributed DMAP catalytic sites (2.02 mmol g-1). DMAP-NCP also exhibits enhanced stability and permanent porosity due to the strong covalent linkage and the rigidity of the "bottom-up" monomers. As a result, DMAP-NCP shows excellent catalytic activity in the acylation of alcohols with yields of 92-99 %. The DMAP-NCP catalyst could be easily recovered from the reaction mixture and reused in at least 14 consecutive cycles without measurable loss of activity. Moreover, the catalytic acylation reaction could be performed under neat and continuous-flow conditions for at least 536 h of continuous work with the same catalyst activity. Copyright
- Zhang, Yuan,Zhang, Yong,Sun, Ya Lei,Du, Xin,Shi, Jiao Yi,Wang, Wei,Wang, Wei David
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experimental part
p. 6328 - 6334
(2012/06/18)
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- Biocatalytic enantiomeric resolution of L-menthol from an eight isomeric menthol mixture through transesterification
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The four diastereomers of menthol and their enantiomers, namely dl-menthol, dl-neomenthol, dl-neoisomenthol and dl-isomenthol, were synthesised by the hydrogenation of thymol to yield an eight isomer liquid menthol. A suitably selective lipase was sought to preferentially esterify l-menthol in organic solvent, hence simplifying separation from the diasteromeric mix through distillation. From an initial screen a commercial Pseudomonas fluorescens lipase (Amano AK) was selected, and vinyl acetate was chosen as a suitable irreversible acyl donor for transesterification. The reaction reagent ratios were optimised, and an enantiomeric excess (ee) of l-menthol of greater than 95% was reproducibly achievable at a conversion of 30% dl-menthol (0.68 M) at ≤50°C. On the basis of the composition of liquid menthol the reaction had a diastereomeric excess (de) of 82%. The enzyme was recycled 150 times in 5 ml batch reactions using liquid menthol and achieving an overall yield of 184.3 g dl-menthol/g commercial enzyme preparation. The by-product acetic acid, formed by hydrolysis of menthyl acetate, was found to cause a high degree of enzyme inactivation. The resolution reaction was scaled up 400 fold to 2 L and the enzyme recycled 38 times with an average conversion of the available l-menthol of 59% and a volumetric productivity of 1.2 g/L/h.
- Brady,Reddy,Mboniswa,Steenkamp,Rousseau,Parkinson,Chaplin,Mitra,Moutlana,Marais,Gardiner
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scheme or table
p. 1 - 10
(2012/03/27)
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- Poly-(N,N′-dibromo-N-ethyl-benzene-1,3-disulfonamide) and N,N,N′,N′- tetrabromobenzene-1,3-disulfonamide as highly efficient catalysts, and (AC2O/SIO2) as a heterogeneous system for the acetylation of alcohols, amines, and thiols under microwave irradiation
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Chemical Equation Presented Poly-(N,N′-dibromo-N-ethyl-benzene-1,3- disulfonamide) (PBBS) and N,N,N′,N′-tetrabromobenzene-1,3- disulfonamide (TBBDA) are good activators and catalytic reagents for the acetylation of alcohols, amines, and thiols. The presented method has the advantages of mild conditions, chemoselectivity, and good to high yields, and uses noncorrosive, inexpensive, recyclable, and environmentally friendly catalysts. We have also demonstrated that combining SiO2 with microwave energy provides an efficient, fast, convenient, and easy workup procedure for the synthesis of mono- and disubstituted acetates, acetamides, and thioacetamides. Copyright Taylor & Francis Group, LLC.
- Veisi, Hojat,Ghorbani-Vaghei, Ramin,Eskandari, Hosna,Hemmati, Saba,Rezaei, Ardashir,Hajinazari, Somaye,Far, Mohammad Raoof Heidari,Entezari, Azam
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experimental part
p. 213 - 219
(2011/04/24)
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- [InCl4]: An efficient catalyst-medium for alkoxymethylation of alcohols and their interconversion to acetates and TMS-ethers
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A simple, green and chemoselective method for methoxymethylation and ethoxymethylation of primary and secondary alcohols using a Lewis acidic room temperature ionic liquid, [C4mim][InCl4], as catalyst and reaction medium under ambient temperature, microwave and ultrasonic irradiations is reported. In this catalytic system, the corresponding MOM-and EOM-ethers are obtained in excellent yields and in short reaction times. Furthermore, this catalytic system was used for mild and efficient transformations of these protected alcohols to their corresponding acetates and trimethylsilyl ethers under thermal conditions and microwave and ultrasonic irradiations.
- Mohammadpoor-Baltork, Iraj,Moghadam, Majid,Tangestaninejad, Shahram,Mirkhani, Valiollah,Khosropour, Ahmad Reza,Mirjafari, Arsalan
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experimental part
p. 568 - 579
(2012/05/05)
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- Synthesis and reactivity studies of a new reagent, ethyltriphenylphosphonium tribromide
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A new reagent, ethyltriphenyl phosphonium tribromide (ETPPTB), has been synthesized and studied. Results show that the reagent is quite efficient for various reactions such as organic bominations, acylations, and isothiocyanate preparation. Copyright
- Jamir, Latonglila,Alimenla,Kumar, Anil,Sinha, Dipak,Sinha, Upasana B.
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experimental part
p. 147 - 155
(2011/03/17)
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- An atom-efficient and powerful method for direct esterification of silyl ethers catalyzed by HClO4-SiO2
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An efficient and convenient procedure for direct esterification of alkyl and aryl silyl ethers with Ac2O and a catalyst system of perchloric acid immobilized on a silica gel (HClO4-SiO2) has been developed. The silyl protecting groups are directly replaced by acetyls and the protecting groups themselves are transformed into acetates as the sole byproducts, which can be readily recovered and converted back to silylchlorides, the original protecting agents, thus minimizing wastes.
- Du, Ti-Jian,Wu, Qin-Pei,Liu, Hai-Xia,Chen, Xi,Shu, Yi-Nan,Xi, Xiao-Dong,Zhang, Qing-Shan,Li, Yun-Zheng
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experimental part
p. 1096 - 1101
(2011/04/16)
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- H3PW12O40at the[bmim][FeCl4]: A green catalytic system for alkoxymethylation of alcohols and their one-pot interconversion to acetates and TMS-ethers
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12-Tungstophosphoric acid immobilized on [bmim][FeCl4] was found to be an efficient catalyst for chemoselective methoxymethylation and ethxoymethylation of alcohols and also one-pot conversion of MOM- or EOM-ethers to their corresponding acetates and TMS-ethers under thermal conditions and microwave irradiation. These procedures were simple, rapid and the corresponding products were obtained in high yields. The catalyst exhibited remarkable reactivity and was reusable.
- Mohammadpoor-Baltork,Moghadam,Tangestaninejad,Mirkhani,Khosropour,Mirjafari
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experimental part
p. 513 - 524
(2012/06/16)
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- DABCO: An efficient promoter for the acetylation of carbohydrates and other substances under solvent-free conditions
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A simple, mild and efficient solvent-free method for the acetylation of carbohydrates, and their partially protected derivatives, as well as non-carbohydrate substances in excellent yields in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) is described with the advantage of tolerance to various functional groups, short reaction time and ease of product isolation.
- Ch, Ratnasekhar,Tyagi, Mohit,Patil, Premanand Ramrao,Kartha, K.P. Ravindranathan
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experimental part
p. 5841 - 5846
(2011/12/03)
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- A mild and efficient method for the methoxymethylation and acetylation of alcohols promoted by benzyltriphenylphosphonium tribromide
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A mild and efficient method for the conversion of alcohols to their corresponding methoxymethyl ethers and acetates using benzyltriphenylphosphonium tribromide (BTPTB) as catalyst is described. All reactions were performed under completely heterogeneous reaction conditions in good to high yields.
- Shirini, Farhad,Imanzadeh, Gholam Hossein,Mousazadeh, Seyyed Ali Reza,Mohammadpoor-Baltork, Iraj,Abedin, Masoumeh
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experimental part
p. 1187 - 1190
(2011/10/05)
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- Microwave-assisted rapid and efficient deprotection and direct esterification and silylation of MOM and EOM ethers catalyzed by [Hmim][HSO 4] as a Bronsted acidic ionic liquid
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1-Methylimidazolium hydrogensulfate, [Hmim] [HSO4], a Bronsted acidic room temperature ionic liquid, is used as a catalyst and reaction medium for facile and ecofriendly deprotection of methoxymethyl (MOM) and ethoxymethyl (EOM) ethers to their corresponding alcohols under thermal conditions (Δ) and microwave irradiation (MW). Furthermore, one-pot interconversion to the respective acetates and trimethylsilyl (TMS) ethers was also achieved. Springer-Verlag 2010.
- Mohammadpoor-Baltork, Iraj,Moghadam, Majid,Tangestaninejad, Shahram,Mirkhani, Valiollah,Khosropour, Ahmad Reza,Mirjafari, Arsalan
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experimental part
p. 1083 - 1088
(2012/06/18)
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- Microwave-assisted synthesis of nano-sized cadmium oxide as a new and highly efficient catalyst for solvent free acylation of amines and alcohols
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In present studies, a new and efficient method for synthesis of cadmium oxide nanoparticles by using microwave (MW) activation is reported. To ensure the specific efficiency of microwave irradiation versus conventional heating, the synthesis of Cd(OH)2 as precursor of CdO was carried out under similar temperature (80 °C), time and reaction conditions without microwave irradiation. The formation of CdO was characterized by XRD, TEM, FT-IR analysis. Catalytic activity of CdO nanopowder for acylation of alcohols, phenols and amines has been investigated. The results show that the reaction times and yields of desired products were improved by using CdO.
- Mazaheritehrani,Asghari,Orimi, R. Lotfi,Pahlavan
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experimental part
p. 2554 - 2564
(2010/10/21)
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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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- Enzymatic production of l-menthol by a high substrate concentration tolerable esterase from newly isolated Bacillus subtilis ECU0554
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Enzymatic preparation of l-menthol has been attracting much attention in the flavor and fragrance industry. A new ideal strain, Bacillus subtilis ECU0554, which exhibited high hydrolytic activity and excellent enantioselectivity towards l-menthyl ester, has been successfully isolated from soil samples through enrichment culture and identified as Bacillus subtilis by 16S rDNA gene sequencing. The esterase extracted from B. subtilis ECU0554 (BSE) showed the best catalytic properties (E > 200) for dl-menthyl acetate among the five menthyl esters examined. Enantioselective hydrolysis of 100 mM dl-menthyl acetate at 30°C and pH 7.0, using crude BSE as biocatalyst and 10% ethanol (v/v) as cosolvent, resulted in 49.0% conversion (3 h) and 98.0% ee for the l-menthol produced, which were much better than those using commercial enzymes tested. Moreover, BSE exhibited strong tolerance against high substrate concentration (up to 500 mM), and the concentration of l-menthol produced could reach as high as 182 mM, and more importantly, the optical purity of l-menthol produced was kept above 97% ee, which were not found in previous reports. These results imply that BSE is a potentially promising bio-catalyst for the large-scale enzymatic preparation of l-menthol. Using this excellent biocatalyst, the enzymatic production of l-menthol will become a mild, efficient, inexpensive and easy-to-use "green chemistry" methodology.
- Zheng, Gao-Wei,Yu, Hui-Lei,Zhang, Jian-Dong,Xu, Jian-He
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experimental part
p. 405 - 414
(2009/11/30)
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- Counterattack mode differential acetylative deprotection of phenylmethyl ethers: Applications to solid phase organic reactions
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A counterattack protocol for differential acetylative cleavage of phenylmethyl ether has been developed. The phenylmethyl moiety is liberated as benzyl bromide that is isolated and reused providing advantages in terms of waste minimization/utilization and atom economy. The applicability of this methodology has been extended for solid phase organic reactions with the feasibility of reuse of the solid support.
- Chakraborti, Asit K.,Chankeshwara, Sunay V.
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supporting information; experimental part
p. 1367 - 1370
(2009/07/04)
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- A simple, general, and highly chemoselective acetylation of alcohols using ethyl acetate as the acetyl donor catalyzed by a tetranuclear zinc cluster
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In the presence of a Zn-cluster catalyst, alcohols are efficiently converted to the corresponding acetate just by refluxing in EtOAc. The mild reaction conditions enabled the reactions of various functionalized alcohols to proceed in good to excellent yield. Moreover, even when a large excess of the acetyl donor is used, the hydroxyl groups are selectively acetylated in the presence of highly nucleophilic aliphatic amino groups, approaching chemoselectivity to that of enzymatic system. Georg Thieme Verlag Stuttgart.
- Iwasaki, Takanori,Maegawa, Yusuke,Hayashi, Yukiko,Ohshima, Takashi,Mashima, Kazushi
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experimental part
p. 1659 - 1663
(2009/12/04)
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- Dual behavior of alcohols in iodine-catalyzed esterification under solvent-free reaction conditions
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The dual behavior phenomenon of alcohols in iodine-catalyzed esterification under solvent-free reaction conditions (SFRCs) is described; the governing factor is the stability of the carbonium ion generated from the alcohol; high concentration reaction conditions (HCRCs) or dilute solutions are much less suitable. In the case of benzylic alcohols, loss of optical activity was noted, whereas alkyl alcohols furnished a product with retention of stereochemistry.
- Jereb, Marjan,Vra?i?, Dejan,Zupan, Marko
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scheme or table
p. 2347 - 2352
(2009/09/06)
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- Enantiomeric differentiation of oxygenated p-menthane derivatives by 13C NMR using Yb(hfc)3
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The 13C NMR behaviour of 21 p-menthanic terpene bearing an oxygenated function (alcohol, ketone, acetate) was examined in the presence of a chiral lanthanide shift reagent (Yb(hfc)3). For each monocyclic compound, we measured the lanthanide-induced shift (LIS) on the signals of the carbons and the splitting of signals allowing the enantiomeric differentiation. Some general features were found about their LIS behaviour: experimental data establishing distinct patterns for carvomenthone-like compounds and menthone-like compounds. The enantiomeric splitting was observed for the majority of signals in the spectrum of each compound. In the case of alcohols and acetates, the influence of the relative stereochemistry (cis vs trans) of isopropyl(ene) and the binding function was discussed. Copyright
- Lanfranchi, Don Antoine,Blanc, Marie-Cecile,Vellutini, Muriel,Bradesi, Pascale,Casanova, Joseph,Tomi, Felix
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experimental part
p. 1188 - 1194
(2009/05/26)
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- N, O-ligand accelerated zinc-catalyzed transesterification of alcohols with vinyl esters
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N-Phenyldiethanolamine (1f) is an efficient ligand for zinc-catalyzed transesterification of alcohols with vinyl acetate (R3 = Me) at room temperature. In the case of using other vinyl esters (R3 = Et, n-Pr, Ph), the corresponding products were easily obtained in the presence of pyridine-type ligand 2 instead of aminoalcohol 1f.
- Mino, Takashi,Hasegawa, Tae,Shirae, Yoshiaki,Sakamoto, Masami,Fujita, Tsutomu
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p. 4389 - 4396
(2008/02/13)
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- Erbium(III) chloride: A very active acylation catalyst
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Erbium(iii) chloride is a powerful catalyst for the acylation of alcohols and phenols. The reaction works well for a large variety of simple and functionalized substrates by using different kinds of acidic anhydrides (Ac 2O, (EtCO)2O, (PriCO)2O, (Bu tCO)2O, and (CF3CO)2), without isomerization of chiral centres. Moreover, the catalyst can be easily recycled and reused without significant loss of activity. CSIRO 2007.
- Dalpozzo, Renato,De Nino, Antonio,Maiuolo, Loredana,Oliverio, Manuela,Procopio, Antonio,Russo, Beatrice,Tocci, Amedeo
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- A mild and efficient acetylation of alcohols, phenols and amines with acetic anhydride using La(NO3)3·6H2O as a catalyst under solvent-free conditions
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A wide variety of alcohols, phenols and amines are efficiently and selectively converted into the corresponding acetates by treatment with acetic anhydride in the presence of catalytic amounts of La(NO3)3·6H2O under solvent-free conditions at room temperature. The method is compatible with acid sensitive hydroxyl protecting groups such as TBDMS, THP, OBz, OBn, Boc and some isopropylidenes and offers excellent yields of the mono acetates of 1,3-, 1,4- and 1,5-diols.
- Reddy, T. Srikanth,Narasimhulu,Suryakiran,Mahesh, K. Chinni,Ashalatha,Venkateswarlu
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p. 6825 - 6829
(2007/10/03)
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- Magnesium bistrifluoromethanesulfonimide as a new and efficient acylation catalyst
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Magnesium bistrifluoromethanesulfonimide catalyzed the acetylation of phenols, alcohols, and thiols under solvent-free conditions at room temperature and in short times. Electron-deficient and sterically hindered phenols provided excellent yields. The catalyst was found to be general for acylation with other anhydrides, such as propionic, isobutyric, pivalic, chloroacetic, and benzoic anhydrides. The rate of acylation was influenced by the electronic and steric factors associated with the anhydride. The reaction with less electrophilic anhydrides (e.g., chloroacetic and benzoic anhydrides) required higher temperature (~80 °C). Chemoselective acetylation, pivalation, and benzoylation took place with acid-sensitive alcohols without any competitive dehydration/rearrangement.
- Chakraborti, Asit K.,Shivani
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p. 5785 - 5788
(2007/10/03)
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- Molecular iodine catalyzed selective acetylation of alcohols with vinyl acetate
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Molecular iodine is found to catalyze the acetylation of alcohols efficiently with vinyl acetate. The reaction is mild and selective with good to high yields. Molecular iodine displays significant functional group tolerance, being compatible with methoxy, double bonds, spiroketals, ketals and phenolic hydroxyl functions.
- Bosco, J.W. John,Agrahari, Aditya,Saikia, Anil K.
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p. 4065 - 4068
(2007/10/03)
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- Synthesis, structure and reactivity of hydrated and dehydrated organotin cations
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Monomeric organotin dications {[nBu2Sn(H2O) 4]2+· 2C6H5SO 3-} and {[nBu2Sn(H2O) 4]2+·1,5-C10H6(SO 3-)2} have been synthesized by the reaction of [nBu2SnO]n and the corresponding arylsulfonic acid. Dodecanuclear organooxotin macrocations {[(nBuSn)12(μ3- O)14(μ2-OH)6]2+·2RSO 3-} (R = C6H5; 2,5-Me 2C6H3) have been synthesized by the reaction of nBuSn(O)(OH) and the corresponding arylsulfonic acid. The X-ray crystal structure of one of the dodecanuclear cages is reported. These organotin cations have been shown to be effective catalysts in acetylation and transacetylation reactions. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Chandrasekhar, Vadapalli,Boomishankar, Ramamoorthy,Gopal, Kandasamy,Sasikumar, Palani,Singh, Puja,Steiner, Alexander,Zacchini, Stefano
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p. 4129 - 4136
(2007/10/03)
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- Efficient one-step conversion of tetrahydropyranyl ethers into acetates and formates in the presence of potassium dodecatungstocobaltate K 5CoW12O40·3H2O
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Tetrahydropyranyl ethers derived from primary alcohols were directly and efficiently converted into the corresponding acetates and formates by the action of ethyl acetate, acetic acid, acetic anhydride, and ethyl formate in the presence of a catalytic amount of potassium dodecatungstocobaltate K 5CoW12O40 ? 3H2O. Tetrahydropyranyl ethers derived from secondary alcohols and phenols can also be transformed into the corresponding acetates with the use of acetic anhydride, but K5CoW12O40 ? 3H2O was ineffective for esterification with ethyl acetate, acetic acid, and ethyl formate.
- Rafiee,Tangestaninejad,Habibi,Mohammadpoor-Baltork,Mirkhani
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p. 393 - 395
(2007/10/03)
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- Nucleophilic acyl substitutions of anhydrides with protic nucleophiles catalyzed by amphoteric, oxomolybdenum species
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(Chemical Equation Presented) Among six different group VIb oxometallic species examined, dioxomolybdenum dichloride and oxomolybdenum tetrachloride were the most efficient catalysts to facilitate nucleophilic acyl substitution (NAS) of anhydrides with a myriad array of alcohols, amines, and thiols in high yields and high chemoselectivity. In contrast to the well-recognized redox chemical behaviors associated with oxomolybdenum(VI) species, the catalytic NAS was unprecedented and tolerates virtually all kinds of functional groups. By using benzoic anhydride as a mediator for in situ generation of an incipient mixed anhydride-MoO2Cl2 adduct with a given functional alkanoic acid, one can achieve oleate, dipeptide, diphenylmethyl, N-Fmoc-α-amino, pyruvic, and tert-butylthio ester, N-tert-butylamide, and trityl methacrylate syntheses with appropriate protic nucleophiles. The amphoteric character of the Mo=O unit in oxomolybdenum chlorides was found to be responsible for the catalytic NAS profile as supported by a control NAS reaction of using an authentic adduct-MoOCl2(O2-CBu t)2 between pivalic anhydride and MoO2Cl 2 as the catalyst.
- Chen, Chien-Tien,Kuo, Jen-Huang,Pawar, Vijay D.,Munot, Yogesh S.,Weng, Shieu-Shien,Ku, Cheng-Hsiu,Liu, Cheng-Yuan
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p. 1188 - 1197
(2007/10/03)
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- Fluoride-promoted oxidation of Fischer alkoxy carbene complexes: Stoichiometric and catalytic conditions
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The utility of fluoride anion as promoter of the oxidation of Fischer carbene complexes is presented. Two different and complementary methods that allow the fast and convenient preparation of carbene-derived esters in good yields have been developed using
- Barluenga, Jose,Andina, Facundo,Fernandez-Rodriguez, Manuel A.,Garcia-Garcia, Patricia,Merino, Isabel,Aguilar, Enrique
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p. 7352 - 7354
(2007/10/03)
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