iodides through a palladium-catalyzed carbonylation followed by an inter- or intramolecular coupling reaction with alcohols to afford the corresponding esters or lactones, respectively. Styrene derivatives were also efficient substrates in an in-situ Mizoroki-Heck-type cross-coupling reaction with aryl iodides, leading to the effective formation of asymmetric stilbenes. The decarbonylation of cinnamaldehyde
Copper-catalyzed highly efficient ester formation from carboxylic acids/esters and formates
作者:Jun Liu、Changdong Shao、Yanghui Zhang、Guangfa Shi、Shulei Pan
DOI:10.1039/c4ob00193a
日期:——
A highly efficient copper-catalyzed protocol for the synthesis of esters has been developed from formates. This protocol is applicable to reactions with either esters or acids as the substrates, and shows broad substrate scopes and high yields.
aldehydes with alcohols as well as dehydrogentive cross-coupling of primary alcohols to produce esters have been developed using a Rh-terpyridine catalyst. The catalyst demonstrates broad substrate scope and good functional group tolerance, affording esters highly selectively. The high chemoselectivity of the catalyst stems from its preference for dehydrogenation of benzylic alcohols over aliphatic ones. Preliminary
已经使用 Rh-三联吡啶催化剂开发了醛与醇的脱氢交叉偶联以及伯醇的脱氢交叉偶联以生产酯。该催化剂表现出广泛的底物范围和良好的官能团耐受性,可高度选择性地提供酯。该催化剂的高化学选择性源于其对苄醇脱氢的偏好优于脂肪醇。初步机理研究表明,活性催化剂是二聚 Rh( II ) 物种,通过涉及金属-基础-金属协同作用的机制进行操作。
Solvent- and Metal-free Oxidative Esterification of Aromatic Aldehydes Using Urea-2,2-dihydroperoxypropane as a New Solid Oxidant
作者:Kaveh Khosravi、Kobra Khalaji、Shirin Naserifar
DOI:10.1002/jccs.201600777
日期:2017.3
Urea‐2,2‐dihydroperoxypropane as a noble and solid gem‐dihydroperoxide derivative was used to transform various aromaticaldehydes to their corresponding benzoate derivatives in the presence of HBr under mild conditions at room temperature in high yields and short reaction times.