Ligand-Controlled Cobalt-Catalyzed Regiodivergent Alkyne Hydroalkylation

Abstract

Regiodivergent alkyne hydroalkylation to generate different isomers of an alkene from the same alkyne starting material would be beneficial; however, it remains a challenge. Herein, we report a ligand-controlled cobalt-catalyzed regiodivergent alkyne hydroalkylation. The sensible selection of bisoxazoline (<b>L1</b>) and pyridine-oxazoline (<b>L8</b>) ligands led to reliable and predictable protocols that provided (<i>E</i>)-1,2-disubstituted and 1,1-disubstituted alkenes with high <i>E</i>/<i>Z</i> stereoselectivity and regioisomeric ratio starting from identical terminal alkyne and alkyl halide substrates and produced trisubstituted alkenes in the case of internal alkynes. This method exhibits a broad scope for terminal and internal alkynes with a wide range of activated and unactivated alkyl halides and shows excellent functional group compatibility.