Cobalt-catalyzed regio- and stereoselective intermolecular enyne coupling: an efficient route to 1,3-diene derivatives
作者:Subramaniyan Mannathan、Chien-Hong Cheng
DOI:10.1039/b920071a
日期:——
The reaction of alkynes with vinyl arenes or vinyl trimethyl silane in the presence of a cobalt(II) complex, Zn and ZnI(2) in CH(2)Cl(2) at rt to 50 degrees C provides 1,3-dienes in good to excellent yields.
PBu<sub>3</sub>-Mediated Vinylogous Wittig Reaction of α-Methyl Allenoates with Aldehydes and Mechanistic Investigations
作者:Silong Xu、Rongshun Chen、Zhengjie He
DOI:10.1021/jo201466k
日期:2011.9.16
A highly stereoselective PBu3-mediated vinylogous Wittigolefination between α-methyl allenoates and a variety of aldehydes is presented as the first example of a practical and synthetically useful vinylogous Wittig reaction. Mechanistic experiments including deuterium-labeling, intermediate entrapment, and NMR monitoring have been deliberately conducted. On the basis of mechanistic investigations