Synthesis and Asymmetric Resolution of α-Azido-peroxides
摘要:
An unprecedented synthesis of alpha-azido-peroxides has been developed using an FeCl3-catalyst starting from carbonyl, TMS-azide, and hydroperoxide. Further, a base promoted decomposition of synthesized secondary alpha-azido-peroxides to provide the corresponding tert-butyl esters has been disclosed. Finally, an asymmetric kinetic resolution of such alpha-azido-peroxides has also been developed to provide chiral a-azido-peroxides in excellent enantiopurity.
Copper-catalyzed oxidative esterification of aldehydes with dialkyl peroxides: efficient synthesis of esters of tertiary alcohols
作者:Yefeng Zhu、Yunyang Wei
DOI:10.1039/c3ra40246k
日期:——
Copper-catalyzed oxidative esterification of aldehydes with dialkyl peroxides has been developed. This protocol affords a novel approach for the synthesis of carboxylic esters of tertiary alcohols under mild conditions. Depending on the catalyst system, a variety of tertiary esters were produced in good to excellent yields.
Silver/manganese dioxide nanorod catalyzed hydrogen-borrowing reactions and <i>tert</i>-butyl ester synthesis
作者:Huanhuan Luo、Yike Yang、Bobin Yang、Zhaojun Xu、Dawei Wang
DOI:10.1177/1747519821989963
日期:2021.7
hydrogen-borrowing reactions in high yields and are also effective for the synthesis of tert-butylesters from aryl cyanides and tert-butyl hydroperoxide in a short period of time. Mechanistic experiments revealed that this catalytic system acts as a Lewis acid in hydrogen-borrowing reactions, while the synthesis of tert-butylesters occurs through a radical pathway. This is the first report on the excellent catalytic
Metal-free radical aromatic carbonylations mediated by weak bases
作者:Denis Koziakov、Axel Jacobi von Wangelin
DOI:10.1039/c7ob01572k
日期:——
We report a new method of metal-free alkoxycarbonylation. This reaction involves the generation of aryl radicals from arenediazonium salts by a very weak base (HCO2Na) under mild conditions. Subsequent radical trapping with carbon monoxide and alcohols gives alkyl benzoates. The conditions (metal-free, 1 equiv. base, MeCN, r.t., 3 h) tolerate various functional groups (I, Br, Cl, CF3, SF5, NO2, ester)
Aluminum Bases for the Highly Chemoselective Preparation of Aryl and Heteroaryl Aluminum Compounds
作者:Stefan H. Wunderlich、Paul Knochel
DOI:10.1002/anie.200804966
日期:2009.2.9
Selective CH activation with a series of neutral aluminum trisamide bases led to a wide range of polyfunctional aryl and heteroarylaluminum reagents. Ester and cyano groups are stable under the reaction conditions for this direct alumination, and donor oxygen substituents are efficient directing groups. High metalation regioselectivities were observed with O,S and N,S heterocycles (see example).