Aluminum Hydride Catalyzed Hydroboration of Alkynes.

Angew Chem Int Ed Engl

University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburg, EH9 3FJ, UK.

Published: December 2016

An aluminum-catalyzed hydroboration of alkynes using either the commercially available aluminum hydride DIBAL-H or bench-stable Et Al⋅DABCO as the catalyst and H-Bpin as both the boron reagent and stoichiometric hydride source has been developed. Mechanistic studies revealed a unique mode of reactivity in which the reaction is proposed to proceed through hydroalumination and σ-bond metathesis between the resultant alkenyl aluminum species and HBpin, which acts to drive turnover of the catalytic cycle.

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http://dx.doi.org/10.1002/anie.201609690DOI Listing

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