title: Cyclopentannulation of conjugated enones using a vinyldiazomethane-based reagent.
abstract: Herein, we describe a two-step method for the cyclopentannulation of conjugated enones using methyl 3-(tert-butyldimethylsilyloxy)-2-diazo-3-butenoate (1) as a bifunctional reagent. The enol silane and stabilized diazoalkane functionalities are exploited independently in sequential Mukaiyama-Michael and diastereoselective α,α'-diketone coupling. Di-, tri-, and tetrasubstituted enones are amenable to annulation under this protocol. Overall, this chemistry is an effective surrogate for a substituted "acetone 1,3-dipole".
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Del Bel
authors.forename: Alexander
authors.initials: A
authors.lastname: Rovira
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Guerrero