Enantiomerically pure 1,3,2-dioxaborolanes: new reagents for the hydroboration of alkynes

Abstract

Stable, enantiomerically pure alkenylboronic esters 2 are conveniently prepared by direct hydroboration employing the new 1,3,2-dioxaborolane 4; their highly diastereoselective cyclopropanation can be achieved.

References

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