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Updated: Jan 12, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Cyclopropylmethyl Boronic Esters as General Reagents in Transition-Metal Catalyzed Homoallylation Reactions
Blanca Lozano1, Javier Teresa1, Israel Fernández2
1Organic Chemistry Department, Universidad Autónoma de Madrid (UAM), 28049 Madrid, Spain.
Abstract:
Herein we disclose the use of cyclopropylmethyl boronates as general reagents in Negishi-type homoallylation reactions. This strategy provides a novel approach to generate enantioenriched homoallyl-Zn species through boron-to-zinc transmetalation. Subsequent sp2-sp3 cross-coupling offers a platform for the preparation of arenes, ketones, and 1,5-dienes containing a chiral homoallylic scaffold. The method has been applied to the late-stage functionalization of known drugs and the preparation of precursors of biologically relevant compounds. Mechanistic experiments and DFT calculations provide insight into the transmetalation/ring-opening sequence.
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