在伯和仲甲硅烷基醚和芳基醚的存在下,由B(C 6 F 5)3 / Et 3 SiH促进的催化C(sp 3)-O键裂解优先与伯甲苯磺酸盐一起进行。这种反应性的差异使几种1,n-二醇的化学选择性脱官能化,并且正交保护的碳水化合物的羟甲基选择性脱氧突出了新方法的效率。具有邻苯基的甲苯磺酸酯在邻氨基苯甲酸辅助下被裂解。
A straightforward synthesis of amides, ureas, and esters is reported by visible-light cross-dehydrogenating coupling (CDC) of aldehydes (or amine carbaldehydes) and amines/R-OTBS ethers by photoredoxcatalysis. The reaction is found to be general and high yielding. A plausible mechanistic pathway has been proposed for these transformations and is supported by appropriate controlled experiments.
PROTECTION OF ALCOHOLS AND ACIDS WITH ALLYLSILANES CATALYZED BY IODINE OR IODOTRIMETHYLSILANE IN CHLORINATED HYDROCARBON
作者:Akira Hosomi、Hideki Sakurai
DOI:10.1246/cl.1981.85
日期:1981.1.5
Many triorganosilyl ethers and esters were prepared by the reaction of allylsilanes with alcohols catalyzed by iodine or iodotrimethylsilane in excellent yields. Bromine and bromotrimethylsilane were also effective catalysts.
New Strategic Reactions for Organic Synthesis: Catalytic Asymmetric C−H Activation α to Oxygen as a Surrogate to the Aldol Reaction
作者:Huw M. L. Davies、Rohan E. J. Beckwith、Evan G. Antoulinakis、Qihui Jin
DOI:10.1021/jo034533c
日期:2003.8.1
The C-H activation of silyl ethers by means of rhodium carbenoid-induced C-H insertion represents a very direct method for the stereoselective synthesis of silyl-protected beta-hydroxy esters. The reaction can proceed with very high regio-, diastereo-, and enantioselectivity and represents a surrogate to the aldol reaction. The reaction is catalyzed by the rhodium prolinate complex Rh(2)(S-DOSP)(4)
Single-Step Dual Functionalization: One-Pot Bromination-Cross-Dehydrogenative Esterification of Hydroxy Benzaldehydes with CCl3Br – A Comparison with Selectfluor
作者:Ranadeep Talukdar
DOI:10.1055/s-0037-1610717
日期:2019.9
Bromination of phenolic compounds without directly using molecular bromine possesses much importance. In this article an IrIII/CCl3Br-assisted single-step double functionalization of hydroxy benzaldehydes is reported. It involves simultaneous esterification of the aldehyde group and bromination of the aryl ring of phenolic aldehydes in one-pot. The reaction proceeds under mild conditions in the presence
不直接使用分子溴对酚类化合物进行溴化具有重要意义。本文报道了 IrIII/CCl3Br 辅助的羟基苯甲醛单步双官能化。它涉及在一锅中同时进行醛基酯化和酚醛芳环的溴化。在 445 nm 蓝光 LED 光的存在下,反应在温和条件下进行,以中等至良好的产率获得高度官能化的溴羟基苯甲酸酯。相比之下,Selectfluor 作为氧化剂只产生非溴酚酸酯。
Process for the preparation of O-silylated hydroxyl compounds and their
申请人:Bayer Aktiengesellschaft
公开号:US05142081A1
公开(公告)日:1992-08-25
This present invention relates to a process for the preparation of O-silylated aliphatic hydroxyl, compounds by the reaction of aliphatic hydroxyl compounds with triorganochlorosilanes and removal of the resulting gaseous hydrogen chloride from the reaction mixture, characterized in that the reaction is carried out in the presence of phase transfer catalysts in the absence of solvent. The invention also relates to the use of the O-silylated hydroxyl compounds obtained by this process as starting materials for the preparation of isocyanates containing ester groups by a reaction with isocyanato carboxylic acid chlorides.