title: Highly stereoselective intramolecular Michael addition using alpha-sulfinyl vinyllithium as an unprecedented Michael donor.
abstract: [figure: see text] The first example of an asymmetric intramolecular Michael addition reaction using alpha-lithiated vinylic sulfoxide as a Michael donor is reported. Michael addition of the alpha-lithiated vinylic sulfoxide to (Z)-enoates proceeds with high diastereoselectivity to give the adducts having a stereogenic center with (R)-configuration at the beta-position of the ester in the cyclopentene ring formation. The selectivity was reversed in the six-membered ring formation. On the other hand, the corresponding (E)-enoates provided Michael adducts with poor diastereoselectivity.
authors: Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: N
authors: N
authors: Maezaki
authors: S
authors: S
authors: Yuyama
authors: H
authors: H
authors: Sawamoto
authors: T
authors: T
authors: Suzuki
authors: M
authors: M
authors: Izumi
authors: T
authors: T
authors: Tanaka