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
Studies on Electrophilic Interaction of 2,3-Allenols with Electrophilic Halogen Reagents: Selective Synthesis of 2,5-Dihydrofurans, 3-Halo-3-alkenals, or 2-Halo-2-alkenyl Ketones
作者:Jing Li、Chunling Fu、Guofei Chen、Guobi Chai、Shengming Ma
DOI:10.1002/adsc.200800088
日期:2008.6.9
iodine (I2) afforded 2,5-dihydrofurans while that of readily available 1-aryl or 1-methyl substituted 2,3-allenols with bromine (Br2), N-bromosuccinimide (NBS), I2 or N-iodosuccinimide (NIS) formed the not easily available but synthetically useful 3-halo-3-alkenals and 2-halo-2-alkenyl ketones with good selectivity and yields via a sequential electrophilic interaction of X+ with the allene moiety, 1,2-aryl
Efficient two-step synthesis of 3-halo-3-enals or 2-halo-2-alkenyl ketones from propargylic bromides via a unique cationic 1,2-aryl or proton shift in electrophilic addition reaction of 2,3-allenols with X+
作者:Chunling Fu、Jing Li、Shengming Ma
DOI:10.1039/b508069j
日期:——
The reaction of readily available 1-substituted 2,3-allenols with Br2, NBS, or I2 afforded the not-easily-available but synthetically useful 3-halo-3-alkenals or 2-halo-2-alkenyl ketones in good yields via a sequential electrophilic interaction of X+ with the allene moiety , a 1,2-aryl or proton shift, and a H+-elimination process; the structures of the products were established by X-ray diffraction