Stereoselective Tandem Bis-Electrophile Couplings of Diborylmethane
Stephanie A Murray1, Michael Z Liang1, Simon J Meek1
1Department of Chemistry, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
Abstract:
A copper-catalyzed three-component linchpin coupling method for the stereoselective union of readily available epoxides and allyl electrophiles is disclosed. Transformations employ [B(pin)]2-methane as a conjunctive reagent, resulting in the formation of two C-C bonds at a single carbon center bearing a C(sp3) organoboron functional group. Products are obtained in 42-99% yield, and up to >20:1 dr. The utility of the approach is highlighted by stereospecific transformations entailing allylation, tandem cross coupling, and application to the synthesis 1,3-polyol motifs.
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