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Carboxylation of sodium arylsulfinates with CO2over mesoporous K-Cu-20TiO2
A mesoporous ternary metal oxide (K-Cu-20TiO2) from a simple sol-gel method was prepared to catalyze heterogeneously the carboxylation reaction of various sodium arylsulfinates under atmospheric carbon dioxide. The catalyst showed excellent selectivity and good functional group tolerance to carboxylation recycle. The oxidation state of active copper(i) by characterization using FTIR, XRD, TG, XPS and TEM techniques proved to be efficacious to conduct atom economical reactions.
Chen, Lei,Chen, Yanjiao,Dai, Xuan,Peng, Xinhua,Wu, Tao,Zhang, Wenwei
p. 772 - 776
(2022/01/22)

Oxidative carbon-carbon bond cleavage of 1,2-diols to carboxylic acids/ketones by an inorganic-ligand supported iron catalyst
The carbon-carbon bond cleavage of 1,2-diols is an important chemical transformation. Although traditional stoichiometric and catalytic oxidation methods have been widely used for this transformation, an efficient and valuable method should be further explored from the views of reusable catalysts, less waste, and convenient procedures. Herein an inorganic-ligand supported iron catalyst (NH4)3[FeMo6O18(OH)6]·7H2O was described as a heterogeneous molecular catalyst in acetic acid for this transformation in which hydrogen peroxide was used as the terminal oxidant. Under the optimized reaction conditions, carbon-carbon bond cleavage of 1,2-diols could be achieved in almost all cases and carboxylic acids or ketones could be afforded with a high conversion rate and high selectivity. Furthermore, the catalytic system was used efficiently to degrade renewable biomass oleic acid. Mechanistic insights based on the observation of the possible intermediates and control experiments are presented.
Chen, Weiming,Xie, Xin,Zhang, Jian,Qu, Jian,Luo, Can,Lai, Yaozhu,Jiang, Feng,Yu, Han,Wei, Yongge
supporting information
p. 9140 - 9146
(2021/11/23)

Photoredox-Catalyzed Simultaneous Olefin Hydrogenation and Alcohol Oxidation over Crystalline Porous Polymeric Carbon Nitride
Booming of photocatalytic water splitting technology (PWST) opens a new avenue for the sustainable synthesis of high-value-added hydrogenated and oxidized fine chemicals, in which the design of efficient semiconductors for the in-situ and synergistic utilization of photogenerated redox centers are key roles. Herein, a porous polymeric carbon nitride (PPCN) with a crystalline backbone was constructed for visible light-induced photocatalytic hydrogen generation by photoexcited electrons, followed by in-situ utilization for olefin hydrogenation. Simultaneously, various alcohols were selectively transformed to valuable aldehydes or ketones by photoexcited holes. The porosity of PPCN provided it with a large surface area and a short transfer path for photogenerated carriers from the bulk to the surface, and the crystalline structure facilitated photogenerated charge transfer and separation, thus enhancing the overall photocatalytic performance. High reactivity and selectivity, good functionality tolerance, and broad reaction scope were achieved by this concerted photocatalysis system. The results contribute to the development of highly efficient semiconductor photocatalysts and synergistic redox reaction systems based on PWST for high-value-added fine chemical production.
Qiu, Chuntian,Sun, Yangyang,Xu, Yangsen,Zhang, Bing,Zhang, Xu,Yu, Lei,Su, Chenliang
p. 3344 - 3350
(2021/07/26)

Synthesis method of 4-ethylbenzoic acid
The invention relates to the field of chemical synthesis, in particular to a synthesis method of 4-ethylbenzoic acid. The synthesis method comprises the following steps: mixing 4-ethylacetophenone with a ketone catalyst, dropwise adding an aqueous solution of sodium hypochlorite, carrying out heating, keeping a temperature, carrying out standing for liquid separation, and carrying out acidity regulation on a water phase. The method is short in reaction period, high in yield (which can reach 96.4%), high in product content (which can reach 97.4%), excellent in product quality, simple to operateand low in energy consumption.
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Paragraph 0007; 0018-0033

(2020/05/11)

Palladium-catalyzed carbonylative synthesis of acylstannanes from aryl iodides and hexamethyldistannane
In this communication, we describe a new method for the carbonylative synthesis of acylstannanes from aryl iodides and hexamethyldistannane. With Pd(PPh3)4 as the catalyst and toluene as the solvent at 60 °C under 10 bar CO for 16 h, the desired acylstannanes were obtained in good to excellent yields. In order to facilitate isolation and analysis, the obtained acylstannanes were transformed into the corresponding benzoic acids by simply stirring under air for 5 h.
Chen, Bo,Franke, Robert,Wu, Xiao-Feng,Xu, Jian-Xing,Yuan, Yang
(2020/07/21)

A Zn(II)-Coordination Polymer for the Instantaneous Cleavage of Csp3-Csp3 Bond and Simultaneous Reduction of Ketone to Alcohol
Two coordination polymers of Zn(II) and Cu(II) with n-butylmalonic acid have been achieved in this work. The crystallographic structural descriptions along with the sedimentary rock-type microstructural morphology of these two coordination polymers (CPs) have been explored. The reactivity of β-hydroxy ketones with these two CPs has also been investigated. The Zn(II)-CP shows a specific reactivity with β-hydroxy ketone at room temperature and in open air conditions. Through a microcolumn-based filtration technique, the Zn(II)-CP shows the capability to break the Csp3-Csp3 σ bonds of β-hydroxy ketone and simultaneously reduce the associated ketone to alcohol. Such conversion has been progressed without the use of any additional external reducing agent and any chemical workup or column chromatographic purification protocol. Other similar type CPs of Cu(II) and Mn(II) with n-butylmalonic acid completely failed to show similar reactivity with β-hydroxy ketone. On the basis of much experimental evidence, the most possible mechanistic pathway of the reactivity between β-hydroxy ketone and Zn(II)-CP has also been proposed through this work.
Das, Gourab Kanti,Dey, Biswajit,Dhibar, Subhendu,Ghosh, Debasish,Gupta, Vivek K.
(2020/04/10)

Hydrogenation reaction method
The invention relates to a hydrogenation reaction method, and belongs to the technical field of organic synthesis. The hydrogenation reaction method provided by the invention comprises the following steps: carrying out a hydrogen transfer reaction on a hydrogen acceptor compound, pinacol borane and a catalyst in a solvent in the presence of proton hydrogen, so that the hydrogen acceptor compound is subjected to a hydrogenation reaction; the catalyst is one or more than two of a palladium catalyst, an iridium catalyst and a rhodium catalyst; the hydrogen acceptor compound comprises one or morethan two functional groups of carbon-carbon double bonds, carbon-carbon triple bonds, carbon-oxygen double bonds, carbon-nitrogen double bonds, nitrogen-nitrogen double bonds, nitryl, carbon-nitrogentriple bonds and epoxy. The method is mild in reaction condition, easy to operate, high in yield, short in reaction time, wide in substrate application range, suitable for carbon-carbon double bonds,carbon-carbon triple bonds, carbon-oxygen double bonds, carbon-nitrogen double bonds, nitrogen-nitrogen double bonds, nitryl, carbon-nitrogen triple bonds and epoxy functional groups, good in selectivity and high in reaction specificity.
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Paragraph 0034; 0065-0068

(2020/05/14)

Generalized Chemoselective Transfer Hydrogenation/Hydrodeuteration
A generalized, simple and efficient transfer hydrogenation of unsaturated bonds has been developed using HBPin and various proton reagents as hydrogen sources. The substrates, including alkenes, alkynes, aromatic heterocycles, aldehydes, ketones, imines, azo, nitro, epoxy and nitrile compounds, are all applied to this catalytic system. Various groups, which cannot survive under the Pd/C/H2 combination, are tolerated. The activity of the reactants was studied and the trends are as follows: styrene'diphenylmethanimine'benzaldehyde'azobenzene'nitrobenzene'quinoline'acetophenone'benzonitrile. Substrates bearing two or more different unsaturated bonds were also investigated and transfer hydrogenation occurred with excellent chemoselectivity. Nano-palladium catalyst in situ generated from Pd(OAc)2 and HBPin extremely improved the TH efficiency. Furthermore, chemoselective anti-Markovnikov hydrodeuteration of terminal aromatic olefins was achieved using D2O and HBPin via in situ HD generation and discrimination. (Figure presented.).
Wang, Yong,Cao, Xinyi,Zhao, Leyao,Pi, Chao,Ji, Jingfei,Cui, Xiuling,Wu, Yangjie
supporting information
p. 4119 - 4129
(2020/08/10)

N-Doped carbon nanofibers derived from bacterial cellulose as an excellent metal-free catalyst for selective oxidation of arylalkanes
N-Doped carbon nanofibers derived from one-step pyrolysis of low-cost bacterial cellulose with the assistance of urea were reported. Owing to their interconnected nanofibrous structure and high specific surface area as well as high N doping, they exhibited excellent catalytic performance for selective oxidation of arylalkanes even with O2 as an oxidant in aqueous solution.
Huang, Runkun,Cao, Changyan,Liu, Jian,Sun, Dongping,Song, Weiguo
supporting information
p. 1935 - 1938
(2019/05/02)

Selective oxidation method for toluene compounds
The invention discloses a selective oxidation method for toluene compounds. The method comprises the following steps: 1, putting a toluene compound represented by a formula (I) shown in the specification, a metalloporphyrin catalyst, an oxidant and a dispersing agent into a ball milling tank, sealing the ball milling tank, carrying out ball milling for 3-24 hours at room temperature and the rotating speed of 100-800 rpm, stopping ball milling once every 1-3 hours in the ball milling process, discharging gas in the ball milling tank, and after the reaction is finished, carrying out post-treatment on the reaction mixture to obtain a product benzoic acid compound represented by a formula (II) shown in the specification. Oxidation conversion of methylbenzene and derivatives thereof is achievedthrough solid-phase ball milling, the reaction mode is novel, the operation is convenient, and the energy consumption is low; an organic solvent and other auxiliaries are not needed, so that use of toxic and harmful organic reagents is effectively avoided, and the method is green and environmentally friendly; the peroxide content is low, and the safety coefficient is high; and benzoic acid and derivatives thereof have high selectivity and meet the social requirements of a green chemical process, an environmental compatibility chemical process and a biological compatibility chemical process inthe prior art.
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Paragraph 0112; 0113

(2019/12/25)

Method for copper-catalyzed carboxylation reaction of arylboronic acid and carbon dioxide
The invention discloses a method for a copper-catalyzed carboxylation reaction of arylboronic acid and carbon dioxide. According to the method, carbon dioxide is used as a C1 source, copper catalysisis adopted, alkoxide serves as alkali, and a reaction is carried out in an organic solvent; the method is simple in process and easy to implement, and shows wide functional group compatibility; the method allows various arylboronic acids such as monosubstituted or polysubstituted phenylboronic acid, polycyclic aromatic hydrocarbon boronic acid and benzoheterocyclic boronic acid to be converted into corresponding arylcarboxylic acids with considerable yield under mild conditions; and the produced carboxylic acids have important application value, and can be used for deriving a great number of other common chemical substances, such as acyl halide, acid anhydride, ester and amide.
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Paragraph 0077; 0078

(2019/12/29)

Palladium-Catalyzed Ligand-Controlled Selective Synthesis of Aldehydes and Acids from Aryl Halides and Formic Acid
Selective synthesis is in the core of modern organic chemistry. In this communication, a novel ligand-dependent palladium-catalyzed carbonylation procedure for the divergent synthesis of aldehydes and carboxylic acids from easily available aryl halides was established. Under the same reaction conditions, the reaction pathway could be controlled by the ligands applied to give formylated and carboxylated products selectively. Sterically hindered monodentate ligands facilitated the reductive carbonylation and provided aldehydes, whereas bidentate ligands preferred the carboxylation reaction and produced carboxylic acids. A wide range of functional groups were tolerated, and the products were, in general, obtained in moderate to excellent yields.
Wu, Fu-Peng,Peng, Jin-Bao,Meng, Ling-Shen,Qi, Xinxin,Wu, Xiao-Feng
p. 3121 - 3124
(2017/08/29)

An outstanding catalyst for the oxygen-mediated oxidation of arylcarbinols, arylmethylene and arylacetylene compounds
A convenient and sustainable protocol for the aerobic oxidation of benzyl alcohols to carbonyl compounds, based on the use of 1,2,4-triazole-type ligands and nickel(ii) bromide, is described. This combination leads to the formation of an exceedingly active, enzyme-like system that allows for other oxidative processes, such as benzylic C-H oxidation and oxygen-mediated cleavage of C-C triple bond, a pioneering procedure for transformation of alkynes into carboxylic acids.
Urgoitia,Sanmartin,Herrero,Domínguez
supporting information
p. 4799 - 4802
(2015/03/18)

Aerobic oxidation at benzylic positions catalyzed by a simple Pd(OAc)2/bis-triazole system
An efficient catalyst system for the Pd-catalyzed aerobic oxidation of benzylic positions has been developed. The combination of palladium(ii) acetate and 3,5-bis((1H-1,2,4-triazol-1-yl)methyl)benzoate ligand allows the selective oxidation at carbon adjacent to arene rings (primary and secondary benzylic alcohols, and other benzyl compounds) to provide the corresponding carbonyl and carboxy derivatives, employing molecular oxygen as oxidizing agent and a very low metal loading (10-5 mol%).
Urgoitia, Garazi,Maiztegi, Ainhoa,Sanmartin, Raul,Herrero, María Teresa,Domínguez, Esther
p. 103210 - 103217
(2015/12/23)

Efficient and convenient oxidation of aldehydes and ketones to carboxylic acids and esters with H2O2 catalyzed by Co4HP2Mo15V3O62 in ionic liquid [TEBSA][BF4]
A simple, efficient, and eco-friendly procedure for the oxidation of aldehydes and ketones to carboxylic acids and esters with H2O2 catalyzed by Co4HP2Mo15V3O62 in ionic liquid [TEBSA][BF4] has been developed. This atom-economical protocol affords the target products in good to high yields. The products can be separated by a simple extraction with organic solvent, and the catalytic system can be recycled and reused without loss of catalytic activity. Additionally, the possible mechanism of oxidation in the catalytic system is proposed. This journal is
Hu, Yu-Lin,Li, De-Jiang,Li, Dong-Sheng
p. 24936 - 24943
(2015/03/30)

Metal Catalyzed Oxidation of Lignin and Related Compounds
Disclosed are methods for the benzylic oxidation of the lignin and related compounds. The methods include contacting lignin with a mixture containing manganese and iron, in the presence of oxygen to produce a carboxylic acid from lignin or a related compound. In some embodiments, the mixture includes cobalt.
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Page/Page column

(2014/09/16)

Two-chamber hydrogen generation and application: Access to pressurized deuterium gas
Hydrogen and deuterium gas were produced and directly applied in a two-chamber system. These gaseous reagents were generated by the simple reaction of metallic zinc with HCl in water for H2 and DCl in deuterated water for D2. The setup proved efficient in classical Pd-catalyzed reductions of ketones, alkynes, alkenes, etc. in near-quantitative yields. The method was extended to the synthesis and isotope labeling of quinoline and 1,2,3,4-tetrahydroquinoline derivatives. Finally, CX-546 and Olaparib underwent efficient Ir-catalyzed hydrogen isotope exchange reactions.
Modvig, Amalie,Andersen, Thomas L.,Taaning, Rolf H.,Lindhardt, Anders T.,Skrydstrup, Troels
p. 5861 - 5868
(2014/07/08)

Commutative reduction of aromatic ketones to arylmethylenes/alcohols by hypophosphites catalyzed by Pd/C under biphasic conditions
An efficient method is reported to reduce aromatic ketones selectively into arylmethylenes or alcohols with hypophosphites and Pd/C, depending on the selected conditions. This study could represent a promising alternative to the classical uses of standard hydrides or molecular hydrogen involved in reduction and deoxygenation procedures.
Guyon, Carole,Baron, Marc,Lemaire, Marc,Popowycz, Florence,Métay, Estelle
p. 2088 - 2095
(2014/03/21)

Inclusion complex containing epoxy resin composition for semiconductor encapsulation
The invention is an epoxy resin composition for sealing a semiconductor, including (A) an epoxy resin and (B) a clathrate complex. The clathrate complex is one of (b1) an aromatic carboxylic acid compound, and (b2) at least one imidazole compound represented by formula (II): wherein R2 represents a hydrogen atom, C1-C10 alkyl group, phenyl group, benzyl group or cyanoethyl group, and R3 to R5 represent a hydrogen atom, nitro group, halogen atom, C1-C20 alkyl group, phenyl group, benzyl group, hydroxymethyl group or C1-C20 acyl group. The composition has improved storage stability, retains flowability when sealing, and achieves an effective curing rate applicable for sealing delicate semiconductors.
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(2014/03/21)

Electrophilicity and nucleophilicity of commonly used aldehydes
The present approach for determining the electrophilicity (E) and nucleophilicity (N) of aldehydes includes a kinetic study of KMNO4 oxidation and NaBH4 reduction of aldehydes. A transition state analysis of the KMNO4 promoted aldehyde oxidation reaction has been performed, which shows a very good correlation with experimental results. The validity of the experimental method has been tested using the experimental activation parameters of the two reactions. The utility of the present approach is further demonstrated by the theoretical versus experimental relationship, which provides easy access to E and N values for various aldehydes and offers an at-a-glance assessment of the chemical reactivity of aldehydes in various reactions. the Partner Organisations 2014.
Pratihar, Sanjay
p. 5781 - 5788
(2014/07/22)

Carbon nitride-catalyzed oxidative cleavage of carbon-carbon bond of α-hydroxy ketones with visible light and thermal radiation
Mesoporous carbon nitride (mpg-C3N4) as a photocatalyst showed higher photocatalytic activities in organic synthesis. Herein we reported a mpg-C3N4-catalyzed oxidation of α-hydroxy ketones to synthesize benzoic acids with visible light. This reaction represented a green and facile route to synthesize benzoic acids for which catalytic approaches were scarce.
Zhan, Haiying,Liu, Wenjie,Fu, Minling,Cen, Jinghe,Lin, Jingxin,Cao, Hua
p. 184 - 189
(2013/10/01)

Direct carboxylation of arenes and halobenzenes with CO2 by the combined use of AlBr3 and R3SiCl
The Lewis acid-mediated direct carboxylation of aromatic compounds with CO2 is efficiently promoted by the addition of silyl chlorides bearing three alkyl and/or aryl substituents in total on the silicon atom. Thus, toluene, xylenes, mesitylene, and some other alkylbenzenes are treated with a 1:1 mixture of AlBr3 and Ph3SiCl in neat substrates under CO2 pressure (3.0 MPa) at room temperature, to give the corresponding carboxylic acids in 60-97% yields, based on AlBr3. Polycyclic arenes, including naphthalene, phenanthrene, and biphenyl, are regioselectively carboxylated in 91-98% yields with the aid of 1 molar equiv of AlBr3 and Ph3SiCl in an appropriate solvent, chosen from benzene, chlorobenzene, and fluorobenzene. These solvents, as well as bromobenzene, resist carboxylation; however, they are also carboxylated in moderate yields when treated with a 1:5 mixture of AlBr3 and iPrSiCl at elevated temperatures. The FT-IR spectrum of a mixture prepared by exposing a suspension of AlBr3 and Ph3SiCl in cyclohexane to CO 2 exhibits an absorption band around 1650 cm-1, assigned to the C=O stretching vibration of a species consisting of CO2, AlBr3, and Ph3SiCl, which suggests that the silyl chlorides activate CO2 in cooperation with AlBr3. 1H NMR analysis of unworked-up reaction mixtures reveals that the products merge as aluminum carboxylates. The mass balance concerning silicon indicates that the silyl chlorides are recycled during the reaction sequence. On the basis of these observations, a feasible mechanism is proposed for the present carboxylation.
Nemoto, Koji,Yoshida, Hiroki,Egusa, Naoki,Morohashi, Naoya,Hattori, Tetsutaro
experimental part
p. 7855 - 7862
(2011/02/21)

Selective oxidation of acetophenones bearing various functional groups to benzoic acid derivatives with molecular oxygen
Acetophenones substituted by alkyl, alkoxy, acetoxy, and halogen groups were selectively oxidized with molecular oxygen to the corresponding benzoic acids by using the N,N',N"-trihydroxyisocyanuric acid (THICA)/cobalt(II) acetate [Co(OAc)2] and THICA/Co(OAc)2/manganese(II) acetate.
Nakamura, Ryota,Obora, Yasushi,Ishii, Yasutaka
experimental part
p. 1677 - 1684
(2011/02/25)

A general and efficient suzuki-miyaura cross-coupling protocol using weak base and no water: The essential mole of acetate
A weak base, CsOAc, promotes Suzuki-Miyaura cross-coupling and related Pd-catalyzed reactions under anhydrous conditions as effectively as stronger bases. Aryl triflates exhibit unusual reaction rates, which are comparable to that: of bromoarenes. A negle
Wang, Bing,Sun, Hui-Xia,Sun, Zhi-Hua
experimental part
p. 3688 - 3692
(2009/12/03)

B-Alkyl Suzuki-Miyaura cross-coupling of tri-n-alkylboranes with arylbromides bearing acidic functions under mild non-aqueous conditions
An efficient and chemoselective Pd-catalyzed B-alkyl Suzuki-Miyaura cross-coupling of tri-n-alkylboranes with arylbromides possessing acidic functions is described. This protocol features the relatively weak base Cs2CO3 and mild non-
Sun, Hui-Xia,Sun, Zhi-Hua,Wang, Bing
experimental part
p. 1596 - 1599
(2009/06/18)

Direct B-alkyl Suzuki-Miyaura cross-coupling of trialkyl-boranes with aryl bromides in the presence of unmasked acidic or basic functions and base-labile protections under mild non-aqueous conditions
An efficient and chemoselective palladium-catalyzed direct B-alkyl Suzuki-Miyaura cross-coupling of trialkylboranes with diversely functionalized aryl bromides is described. A wide variety of unmasked acidic or basic functions are tolerated. The mild non-
Wang, Bing,Sun, Hui-Xia,Sun, Zhi-Hua,Lin, Guo-Qiang
experimental part
p. 415 - 422
(2009/10/23)

Bioavailable diacylhydrazine ligands for modulating the expression of exogenous genes via an ecdysone receptor complex
The present invention relates to non-steroidal ligands for use in nuclear receptor-based inducible gene expression system, and a method to modulate exogenous gene expression in which an ecdysone receptor complex comprising: a DNA binding domain; a ligand binding domain; a transactivation domain; and a ligand is contacted with a DNA construct comprising: the exogenous gene and a response element; wherein the exogenous gene is under the control of the response element and binding of the DNA binding domain to the response element in the presence of the ligand results in activation or suppression of the gene.
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Page/Page column 29

(2008/06/13)

Facile electrochemical transformation of diazonium salts into carboxylic acids
The electrolyses of aryldiazonium tetrafluoroborates in dry DMF and Bu4NHSO4 as solvent-supporting electrolyte system, in the presence of CO2 led to the corresponding arylcarboxylic acids in very good yields.
Otero, M. Dolores,Batanero, Belen,Barba, Fructuoso
p. 8215 - 8216
(2007/10/03)

Selective reduction of alkenes, α,β-unsaturated carbonyl compounds, nitroarenes, nitroso compounds, N,N-hydrogenolysis of azo and hydrazo functions as well as simultaneous hydrodehalogenation and reduction of substituted aryl halides over PdMCM-41 catalyst under transfer hydrogen conditions
Chemoselective reductions of alkenes, α,β-unsaturated carbonyl compounds, nitro and nitroso compounds, N,N-hydrogenolysis of azo and hydrazo functions as well as simultaneous reduction and hydrodehalogenation of substituted aryl halides, including bulkier substrates, were achieved by catalytic transfer hydrogenation (CTH) using mesoporous PdMCM-41 catalyst. The yields were practically unaffected upon recycling of the catalyst. Further, the CTH process is accomplished without affecting the reduction of any other reducible functional group.
Selvam, Parasuraman,Sonavane, Sachin U.,Mohapatra, Susanta K.,Jayaram, Radha V.
p. 3071 - 3075
(2007/10/03)

Highly selective and efficient conversion of alkyl aryl and alkyl cyclopropyl ketones to aromatic and cyclopropane carboxylic acids by aerobic catalytic oxidation: A free-radical redox chain mechanism
An efficient and convenient method has been developed for the oxidation of aryl alkyl and cyclopropyl alkyl ketones to aromatic and cyclopropane carboxylic acids by molecular oxygen at atmospheric pressure, catalysed by Mn(NQ3)2 in combination with Co(NO3)2 or Cu(NO3)2. This simple, cheap and highly selective process has a general character for the synthesis of carboxylic acids and it is particularly suitable for industrial applications.
Minisci, Francesco,Recupero, Francesco,Fontana, Francesca,Bj?rsvik, Hans-Rene?,Liguori, Lucia
p. 610 - 612
(2007/10/03)

Efficient chemoselective carboxylation of aromatics to arylcarboxylic acids with a superelectrophilically activated carbon dioxide-Al2Cl6/Al system
Aromatic carboxylic acids are obtained in good to excellent yield essentially free of diaryl ketones by carboxylation of aromatics with a carbon dioxide-Al2Cl6/Al system at moderate temperatures (20-80°C). To optimize reaction condit
Olah, George A.,Toeroek, Bela,Joschek, Jens P.,Bucsi, Imre,Esteves, Pierre M.,Rasul, Golam,Prakash, G. K. Surya
p. 11379 - 11391
(2007/10/03)

Hydrogenation of alkenes or alkynes using decaborane in methanol
Alkenes and alkynes were reduced to corresponding alkanes in methanol using decaborane (B10H14) in the presence of Pd/C as catalyst under nitrogen in high yields. (C) 2000 Elsevier Science Ltd.
Lee, Seung Hwan,Park, Yong June,Yoon, Cheol Min
p. 887 - 889
(2007/10/03)

Oxidation catalytic system and oxidation process using the same
A substrate (e.g., a cycloalkane, a polycyclic hydrocarbon, an aromatic compound having a methyl group or methylene group adjacent to an aromatic ring) is oxidized with oxygen in the presence of an oxidation catalyst comprising an imide compound of the following formula (1) (e.g., N-hydroxyphthalimide), and a co-catalyst (except phosphovanadomolybdic acid) containing an element selected from the group consisting of Group 2A elements of the Periodic Table of Elements, transition metals (Group 3A to 7A elements, Group 8 elements, Group 1B elements and Group 2B elements of the Periodic Table of Elements) and Group 3B elements of the Periodic Table of Elements, for the formation of an oxide (e.g., a ketone, an alcohol, a carboxylic acid): STR1 wherein R1 and R2 represent a substituent such as a hydrogen atom or a halogen atom, or R1 and R2 may together form a double bond or an aromatic or nonaromatic 5- to 12-membered ring, X is O or OH, and n is 1 to 3.
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(2008/06/13)

Effect of substituent character on carbonylation of aryl halides in two-phase systems
Effect of substituent character in the ring of aryl bromides on their reactivity in carbonylation resulting in aromatic acids. The reaction was carried out in two-phase system p-xylene - water in the presence of palladium-phosphinic catalysts. Optimal conditions of preparation of arylcarboxylic acids were developed.
Lapidus,Petrovskii,Bruk,Beletskaya
p. 1636 - 1639
(2007/10/03)

Synthesis of Derivatives of 4-Ethylbenzoic and 4-Ethylcyclohexanecarboxylic Acids
A procedure has been developed for preparation of derivatives of 4-ethylbenzoic and 4-ethycyclohexanecarboxylic acids via liquid-phase catalytic oxidation and hydrogenation. From 4-ethylbenzoyl chloride the corresponding esters and N-arylamides have been synthesized, and from 4-ethylcyclohexanecarbonyl chloride, the corresponding N-arylamides.
Betnev,Obukhova,Budanov,Danilova,Obukhov
p. 86 - 89
(2007/10/03)

Reduction of olefins on solid support using diimide
The reduction of solid supported olefinic substrate using diimide is described. The diimide, prepared from sulfonylhydrazide, was found to efficiently reduce the olefinic substrates. Typically, the reaction proceeds in over 90% yield to afford the reduction product cleanly after cleavage from the Wang resin.
Lacombe, Patrick,Castagner, Bastien,Gareau, Yves,Ruel, Rejean
p. 6785 - 6786
(2007/10/03)

Carbonylation of aryl halides in a two-phase system in the presence of palladium complexes
Carbonylation of aryl halides in aqueous-organic systems in the presence of palladium complexes has been studied. The effects of the ligand nature (hydrophobic or hydrophilic phosphine) and its amount, phase-transfer catalyst, concentration of the base, solvent, and other factors have been examined. Watersoluble catalysts are less efficient than those soluble in organic solvents. Iodobenzene and p-dibromobenzene react more readily than bromobenzene, whereas carbonylation of p- and o-bromotoluenes is more difficult. The carbonylation of bromobenzene in a mixture with iodobenzene is faster than in the absence of the latter. When the rate-determining stage in the carbonylation of aryl bromides is oxidative addition of the substrate to Pd(0) complex, quaternary ammonium salts and iodine compounds act as catalyst promotors.
Beletskaya,Lapidus,Petrovskii
p. 1464 - 1470
(2007/10/03)

Palladium catalyzed cross-coupling reaction of Grignard reagents with halobenzoic acids, halophenols and haloanilines
Convenient syntheses of substituted benzoic acids, phenols and anilines have been achieved by using palladium catalyzed cross-coupling reactions between Grignard reagents and aryl halides containing carboxy, hydroxy and amino groups without a protection-deprotection sequence.
Bumagin, Nikolai A.,Luzikova, Elena V.
p. 271 - 273
(2007/10/03)

Process for preparation of 1-acyl-2-substituted hydrazines
The present invention can provide a process for the preparation of an 1-acyl-2-substituted hydrazine compound from a mixture containing the 1-acyl-2-substituted hydrazine and an 1-acyl-1-substituted hydrazine by selective hydrolysis or alcoholysis of the 1-acyl-yl-1-substituted hydrazine in the presence of an acid catalyst, and by separation of the resulting carboxylic acid and derivative thereof. The 1-acyl-2-alkyl hydrazine obtained has a high purity.
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(2008/06/13)

Kinetics and mechanism of oxidation of γ-oxoacids by acid permanganate
Kinetics of oxidation of unsubstituted and substituted γ-oxoacids by acid permanganate in aqueous acetic acid medium have been studied at high and low +>.At high +>, the reaction is first order each in , -> and +>.At low +> the reaction is zero order in -> and first order each in +> and the .Variation in ionic strength of the reaction medium has no significant effect on the rate of oxidation.But the rate of the reaction is enhanced by lowering the dielectric constant of the reaction medium.Electron-releasing substituents in the aromatic ring accelerate the reaction rates and electron-withdrawing substituents retard them.The value of the reaction constant (ρ) at 303 K (at+) = 1M) obtained from the Hammett's plot is - 1.49 (corr. coeff. = 0.998) A mechanism consistent with the observed results has been suggested and the related rate laws deduced.Activation parameters have been computed.
Sikkandar, G.,Ahamed, K. A. Basheer,Kannan, S.
p. 845 - 848
(2007/10/02)

Oxidation of aldehydes by sodium chlorite
Oxidation of aldehydes by sodium chlorite.Sodium chlorite is an efficient reagent for the oxidation of aldehydes to the corresponding acids.The reactions were carried out at room temperature in dichloromethane-acetic acid solution for all aldehydes except salicylaldehydes.We show that these compounds can be oxidized using a DMSO-sodium methanolate solution.Yields are good, even in the case of aromatic aldehydes with electron donating groups.
Bayle, J. P.,Perez, F.,Courtieu, J.
p. 565 - 567
(2007/10/02)

On the Generation and Characterization of the Spirooctadienyl Anion in the Gas Phase
Three routes have been explored in both a high-pressure chemical ionization (CI) source and a low-pressure Fourier transform ion cyclotron resonance (FT-ICR) cell to generate the spirooctadienyl anion in the gas phase: (i) proton abstraction from spiroocta-4,6-diene; (ii) expulsion of trimethylsilyl fluoride by phenyl ring participation following fluoride anion attack upon the silicon centre of 2-phenylethyl trimethylsilane; and (iii) collisionally induced dissociation (CID) of the carboxylate anion of 3-phenylpropanoic acid via carbon dioxide loss.From comparison of the CID spectra of various reference (1-) ions with those of the (1-) ions with those of the (1-) ions which could be generated via the routes (i) and (iii) in the CI source it can be concluded that only the third route yields a (1-) in whose CID spectrum is not inconsistent with the one expected for the spirooctadienyl anion.In the FT-ICR cell (1-) ions are generated along all three routes; their structures have been identified by specific ion-molecule reactions and appear to be different.Route (i) yields an α-methyl benzyl anion, probably due to isomerization within the ion-molecule complex formed.An ortho-ethylphenyl anions is formed along route (ii), presumably due to an intramolecular ortho proton abstraction in the generated trimethylsilyl fluoride solvated 2-phenylethyl primary carbanion.The (1-) ion formed along route (iii) shows reactions similar to those of the 1,1-dimethylcyclohexadienyl anion which is structurally related to the spirooctadienyl anion.Furthermore, the (1-) ion generated via route (iii) reacts with hexafluorobenzene under expulsion of only one hydrogen fluoride molecule which contains exclusively one of the original phenyl ring hydrogen atoms.On the basis of all these observations it is therefore quite likely that the spirooctadienyl anion is formed by collisionally induced decarboxylation of the 3-phenylpropanoic acid carboxylate anion and can be a long-lived and stable species in the gas phase.
Maas, Wilfrid P. M.,Veelen, Peter A. van,Nibbering, Nico M. M.
p. 546 - 558
(2007/10/02)

CARBOXYLATION OF ARENES
A two-step procedure for the carboxylation of aromatic rings is described, involving the intermediate preparation of 1-aryl-2,2,2-trichloroethanols (1), which form the corresponding benzoic acids by treatment with NaOH/H2O2.
Menegheli, Paulo,Rezende, Marcos Caroli,Zucco, Cezar
p. 457 - 464
(2007/10/02)

OXIDATIVE COUPLING THE TOLUIC ACID DIANION SYSTEM
The behavior of all three toluic acid isomers upon treatment with two equivalents of base followed by the addition of iodide-containing reagents is described.
Belletire, J. L.,Spletzer, E. G.
p. 575 - 584
(2007/10/02)

Oxidation by Metal Ions. 6. Intramolecular Selectivity in the Side-Chain Oxidation of p-Ethyltoluene and Isodurene by Cobalt(III), Cerium(IV), and Manganese(III)
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Baciocchi, Enrico,Mandolini, Luigi,Rol, Cesare
p. 3906 - 3909
(2007/10/02)