Recyclable Hypervalent Iodine(III) Reagent Iodosodilactone as an Efficient Coupling Reagent for Direct Esterification, Amidation, and Peptide Coupling
作者:Jun Tian、Wen-Chao Gao、Dong-Mei Zhou、Chi Zhang
DOI:10.1021/ol301085v
日期:2012.6.15
hypervalent iodine(III) reagent plays a novel role as an efficient coupling reagent to promote the direct condensation between carboxylicacids and alcohols or amines to provide esters, macrocyclic lactones, amides, as well as peptides without racemization. The regeneration of iodosodilactone (1) can also be readily achieved. The intermediate acyloxyphosphonium ion C from the activation of a carboxylic acid
Cp(2)Sm(thf)(2) was found to be an efficient catalyst for the acylation of alcohols and amines with esters under mild conditions. In the present acylation, vinyl and isopropenyl acetates served as good acylating agents. Thus, a variety of alcohols and amines underwent acylation with vinyl and isopropenyl acetates in the presence of Cp(2)Sm(thf)(2) to give the corresponding esters and amides in good
Novel Brønsted Acidic Ionic Liquids and Their Use as Dual Solvent−Catalysts
作者:Amanda C. Cole、Jessica L. Jensen、Ioanna Ntai、Kim Loan T. Tran、Kristin J. Weaver、David C. Forbes、James H. Davis
DOI:10.1021/ja026290w
日期:2002.5.1
The reaction of triphenylphosphine or N-butylimidazole with cyclic sultones gives zwitterions that are subsequently converted into ionic liquids by reaction with trifluoromethane sulfonic acid or p-toluenesulfonic acid. The resulting ionic liquids have cations to which are tethered alkane sulfonic acid groups. These Brønsted acidic ionic liquids are useful solvent/catalysts for several organic reactions
[EN] PROCESSES FOR PRODUCING CARBOXYLIC ACIDS<br/>[FR] PROCÉDÉS DE PRODUCTION D'ACIDES CARBOXYLIQUES
申请人:EASTMAN CHEM CO
公开号:WO2020205348A1
公开(公告)日:2020-10-08
Processes are disclosed for preparing carboxylic acids from organic esters, the processes comprising contacting an ester with water in the presence of an acid catalyst and a homogenizing solvent at conditions effective to form a carboxylic acid. The homogenizing solvent is present in an amount sufficient to form a single-phase reaction mixture comprising the ester, water, and homogenizing solvent. The homogenizing solvent may be selected from acetonitrile, dimethyl sulfoxide, and 1,4-dioxane.
alcohols catalyzed by mesoporous metal oxides (manganese and cobalt oxides) is reported under base and solvent free conditions. For a range of aliphatic alcohols, up to 90 % conversions to esters was achieved. The catalytic reaction is likewise applicable to neat aldehydes as substrates with yields of up to 86 %. High pressure batch reaction for ethanol to ethyl acetate led to 22 % yield. Isotope labeling