Novel [4 + 2]-Cycloaddition of 1-Phenyl-1-benzothiophenium Salts with Dienes. Experimental Evidence for a Lack of Aromaticity in the Thiophene Ring
作者:Tsugio Kitamura、Bian-Xiang Zhang、Yuzo Fujiwara
DOI:10.1021/jo020406p
日期:2003.2.1
The [4 + 2]-cycloaddition reaction of 1-phenyl-1-benzothiophenium triflates has been conducted for the first time. [4 + 2]-Cycloaddition with dienes such as cyclopentadiene and 1,3-diphenylisobenzofuran occurs successfully to give cycloadducts. This result indicates that the C=C bond of the thiophene ring acts as a 2pi electron component in the cycloadditionreaction. Cycloadducts were formed in high