Tandem ring-closing metathesis/transfer hydrogenation: practical chemoselective hydrogenation of alkenes
Timothy Connolly1, Zhongyu Wang, Michael A Walker
1Bristol-Myers Squibb Research & Development , Department of Discovery Chemistry, 5 Research Parkway, Wallingford, Connecticut 06492, United States.
Abstract:
An operationally simple chemoselective transfer hydrogenation of alkenes using ruthenium metathesis catalysts is presented. Of great practicality, the transfer hydrogenation reagents can be added directly to a metathesis reaction and effect hydrogenation of the product alkene in a single pot at ambient temperature without the need to seal the vessel to prevent hydrogen gas escape. The reduction is applicable to a range of alkenes and can be performed in the presence of aryl halides and benzyl groups, a notable weakness of Pd-catalyzed hydrogenations. Scope and mechanistic considerations are presented.
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