Diastereoselective Addition of Organocerium(III) Reagents Derived from 3-Substituted Propargyl Bromides to Aldehydes [1]

Abstract

Various cerium allenyl reagents were generated by transmetallation of allenyl Grignard compounds with CeCl₃ and sub­sequent conversion into homopropargylic alcohols by addition to various aliphatic and aromatic aldehydes. The α-acetylenic alcohols were obtained with regioselectivities and diastereoselectivities up to 98% de in favor of the threo-diastereomers.

lanthanides - organometallic reagents - addition reactions - diastereoselectivity - regioselectivity

References and Notes

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