An Efficient CuCN-Catalyzed Synthesis of Optically Active 2,3-Allenols from Optically Active 1-Substituted 4-Chloro-2-butyn-1-ols
作者:Jing Li、Wangqing Kong、Chunling Fu、Shengming Ma
DOI:10.1021/jo900710e
日期:2009.7.17
The sequential treatment of opticallyactive terminal propargylic alcohols with n-BuLi/(HCHO)n and regioselective chlorination afforded the corresponding opticallyactive 4-chloro-2-butyn-1-ols. With R1 being a methyl or an ethyl group, an alternative for the synthesis of the corresponding opticallyactive propargylic alcohols is the Novozym 435-catalyzed kinetic resolution of these racemic 4-chloro-2-butyn-1-ols
Indium and zinc-mediated Barbier-type addition reaction of 2,3-allenals with allyl bromide: an efficient synthesis of 1,5,6-alkatrien-4-ols
作者:Wangqing Kong、Chunling Fu、Shengming Ma
DOI:10.1039/b812869c
日期:——
A zinc or indium-mediated Barbier-type addition reaction of 2,3-allenals with allyl bromide in a mixed medium of aqueous NH4Cl and THF (5 : 2) was developed to provide an efficient route to 1,5,6-alkatrien-4-ols, which is synthetically very useful. No 1,4-addition reaction was observed. Depending on the substrates, both indium and activated zinc afforded the 1,2-addition products in moderate to excellent yields: for terminal allenals, activated zinc was better while in other cases the yields with indium were relatively higher.