Brønsted acid mediated nitrogenation of propargylic alcohols: an efficient approach to alkenyl nitriles
作者:Xiaoqiang Huang、Ning Jiao
DOI:10.1039/c4ob00888j
日期:——
A novel and efficient approach to alkenyl nitriles from readily available propargylic alcohols has been developed. This nitrogenation reaction is transition-metal-free and could be conducted under air at ambient temperature, which makes this protocol promising and practical. Moreover, NH4Br is disclosed as an efficient additive to promote the stereoselectivity of this reaction.
Alpha,beta-unsaturated nitriles are readily synthesized by eliminating MgO from beta-hydroxynitriles. Deprotonating acyclic, and cyclic, beta-hydroxynitriles with excess MeMgCl smoothly generates dianion intermediates that eject MgO with concurrent formation of alpha,beta-unsaturated nitriles. Alternatively, sequential addition of lithioacetonitrile and MgBr(2) to aldehydes and ketones generates magnesium
Highly Efficient Rh-Catalyzed Asymmetric Hydrogenation of α,β-Unsaturated Nitriles
作者:Qiaozhi Yan、Duanyang Kong、Meina Li、Guohua Hou、Guofu Zi
DOI:10.1021/jacs.5b06418
日期:2015.8.19
A highly efficient enantioselectivehydrogenation of α,β-unsaturated nitriles catalyzed by Rh-(R,R)-f-spiroPhos complex has been developed. With Rh-(R,R)-f-spiroPhos catalyst and under mild conditions, a wide range of α,β-unsaturated nitriles including the (E)- and (Z)-isomers of 3-alkyl-3-aryl, 3,3-diaryl, and 3,3-dialkyl α,β-unsaturated nitriles were hydrogenated to the corresponding chiral nitriles