By using a charcoal supported nano Cu0 catalyst (Cu/C), a highly efficient oxidation of α-diazo esters to α-ketoesters with molecular oxygen as the sole oxidant has been developed. In the presence of the Cu/C catalyst, 2-aryl-α-diazo esters with both electron-donating and electron-withdrawing groups can be oxidized to the corresponding α-ketoesters efficiently. Furthermore, this Cu/C catalyst can catalyse
Esters of .alpha.-hydroperoxy-bis-p-halo-phenylacetic acids
申请人:Yeda Research & Development Co., Ltd.
公开号:US04066785A1
公开(公告)日:1978-01-03
New esters of the .alpha.-hydroperoxy-bis-p-chloro-(or-bromo)-phenylacetic acids useful as acaricides, process for the preparation of same and compositions containing such materials.
新的α-过氧基双对氯(或溴)苯乙酸酯类化合物,可用作杀螨剂,制备方法及含有这类物质的组合物。
Boron‐Catalyzed C−C Functionalization of Allyl Alcohols
talyzed C−C bond functionalization of arylallyl alcohols using donor‐acceptor carbenes is presented. The allylic hydroxyl group is found to assist the product formation by neighboring group participation providing a clue towards mechanistic understanding. This method can also be employed to effect homologation of allylalcohols to homoallyl alcohols. Overall, this metal‐free transformation presents
Catalyst-free, visible-light-promoted S–H insertion reaction between thiols and α-diazoesters
作者:Jingya Yang、Ganggang Wang、Shuwen Chen、Ben Ma、Hongyan Zhou、Menghui Song、Cai Liu、Congde Huo
DOI:10.1039/d0ob02006k
日期:——
A visible-light-promoted S–H insertion reaction betweenthiols and α-diazoesters was developed. The reaction proceeded smoothly at room temperature with a broad substrate scope, affording various thioethers in moderate to excellent yields. The catalyst- and additive-free nature, sustainable energy source and mild reaction conditions make this strategy more eco-friendly.
Tetraarylphosphonium-Supported Carbodiimide Reagents: Synthesis, Structure Optimization and Applications
作者:Maryon Ginisty、Marie-Noelle Roy、André B. Charette
DOI:10.1021/jo702417v
日期:2008.4.1
esterification reactions, amidation reactions and dehydration reactions of hydroxyesters. Taking advantage of the solubility properties imparted by the tetraarylphosphonium unit, a simple precipitation and filtration allowed complete separation of the urea by-products. This paper describes the structure optimization study of the various TAP-supported carbodiimide reagents to obtain the desired reactivity and