[4+1]-anionic annulation approach to phenylsulfonyl substituted cyclopentenes

Article abstract of DOI:10.1016/0040-4039(93)89019-M

2,3-Bis(phenysulfonyl)-1,3-butadiene undergoes a [4+1]-annulation reaction with a variety of soft carbanions to give phenylsulfonyl substituted cyclopentenes in good yield.