Diastereo- and Enantioselective Synthesis of (E)-δ-Boryl-Substituted anti-Homoallylic Alcohols in Two Steps from Terminal Alkynes.

Angew Chem Int Ed Engl

Department of Synthetic Chemistry and Biological Chemistry, Kyoto University, Katsura, Kyoto, 615-8510, Japan.

Published: October 2019

We report the highly diastereo- and enantioselective preparation of (E)-δ-boryl-substituted anti-homoallylic alcohols in two steps from terminal alkynes. This method consists of a cobalt(II)-catalyzed 1,1-diboration reaction of terminal alkynes with B pin and a palladium(I)-mediated asymmetric allylation reaction of the resulting 1,1-di(boryl)alk-1-enes with aldehydes in the presence of a chiral phosphoric acid. Propyne, which is produced as the byproduct during petroleum refining, could be used as the starting material to construct homoallylic alcohols that are otherwise difficult to synthesize with high stereocontrol.

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http://dx.doi.org/10.1002/anie.201908299DOI Listing

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