title: Stereoselective [4 + 1] annulation reactions with silyl vinylketenes derived from Fischer carbene complexes.
abstract: Stable silyl vinylketenes were prepared via the thermal reaction of Fischer carbene complexes with triisopropylsilyl- or tert-butyldimethylsilyl-substituted alkynes. The ability of these silyl vinylketenes to participate with carbenoid reagents in [4 + 1] annulation reactions was investigated. The best results were obtained with diazomethane and substituted diazomethane reagents, which provided cyclopentenone products in excellent yields and essentially complete stereoselectivity.
authors.affiliation: Department of Chemistry, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, USA. wmoser@mmm.com
authors.forename: William H
authors.initials: WH
authors.lastname: Moser
authors.forename: Laura A
authors.initials: LA
authors.lastname: Feltes
authors.forename: Liangdong
authors.initials: L
authors.lastname: Sun
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Giese
authors.forename: Ryan W
authors.initials: RW
authors.lastname: Farrell