title: Synthesis of 4-Alkyl-4-alkoxybutenolides Having Unsaturated Side Chains via Chromium Carbene Complex Photochemistry: (+)-Cerulenin.
abstract: The photochemical reaction between optically active ene carbamates and chromium alkoxycarbene complexes containing unsaturated aliphatic side chains was further developed. Although remote olefinic groups, including conjugated dienes, were tolerated, a homoallylic side chain underwent intramolecular reaction to give a strained cyclobutanone. (+)-Cerulenin was synthesized utilizing the photochemical reaction of an alkynylcarbene complex with an optically active ene carbamate and the bis(pi-crotyl)nickel halide alkylation of a vinyl bromide as key steps.
authors.affiliation: Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523.
authors.forename: Tracey E.
authors.initials: TE
authors.lastname: Kedar
authors.forename: Michael W.
authors.initials: MW
authors.lastname: Miller
authors.forename: Louis S.
authors.initials: LS
authors.lastname: Hegedus