PdCl<sub>2</sub>/NaI-Catalyzed Homodimeric Coupling-Cyclization Reaction of 2,3-Allenols: An Efficient Synthesis of 4-(1‘,3‘-Dien-2‘-yl)-2,5-dihydrofuran Derivatives
作者:Youqian Deng、Yihua Yu、Shengming Ma
DOI:10.1021/jo702332m
日期:2008.1.1
A PdCl2/NaI-catalyzed homodimeric coupling-cyclizationreaction of 2,3-allenols was observed to provide an efficient route to 4-(1‘,3‘-dien-2‘-yl)-2,5-dihydrofuranderivatives. By using the easily available optically active starting materials, 2,5-dihydrofurans with high enantiopurity may be prepared. A Pd(II)-catalyzed mechanism was also discussed.
One-Pot Construction of Aza- or Oxa-Bridged Benzocycloheptanes from Readily Available 2,3-Allenyl Malonates or 2,3-Allenols and<i>o</i>-Iodobenzaldehyde or Imine
作者:Qiankun Li、Xinpeng Jiang、Chunling Fu、Shengming Ma
DOI:10.1021/ol102811x
日期:2011.2.4
A Pd(OAc)(2)-catalyzed reaction of 2,3-alkadienyl malonates or 2,3-allenols with o-lodobenzaldehyde or Its N-tosyl imine occurred smoothly In MeCN at 80 degrees C to form the oxa- or aza-bridged benzocycloheptane derivatives with Important biological potential. With the optically active 2,3-allenols, the absolute configurations of all the three chiral centers have been conveniently established.
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.