Diastereoselective Formation of Cyclopropanols by a Chromium(II)-mediated Cross-coupling Reaction
نویسندگان
چکیده
Steffen Lang and Ulrich Groth Fachbereich Chemie and Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany Reprint requests to Prof. Ulrich Groth. Fax ++49(7531)884155. E-mail: [email protected] Z. Naturforsch. 2009, 64b, 980 – 984; received April 27, 2009 Various 2-(α-hydroxyalkyl)cyclopropanols were generated by chromium(II)-mediated crosscoupling of acroleins and aldehydes with high diastereoselectivities up to 95%. The unstable diols were converted selectively to the stable monosilyl ethers by treatment with TBDMS-Cl in the presence of the second secondary alcohol.
منابع مشابه
Chromium-catalyzed pinacol-type cross-coupling: studies on stereoselectivity.
A chromium-catalyzed pinacol-type cross-coupling reaction between alpha,beta-unsaturated carbonyl compounds and aldehydes is reported. Even sterically demanding substrates could be coupled to afford the corresponding pinacols in good yields. Systematic studies concerning the origin of the diastereoselectivities led to the proposal of a mechanism for this synthetically useful reaction. Acroleins...
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