E-Selective Semi-Hydrogenation of Alkynes by Heterobimetallic Catalysis
Malkanthi K Karunananda1, Neal P Mankad1
1Department of Chemistry, University of Illinois at Chicago , 845 West Taylor Street, Chicago, Illinois 60607, United States.
Abstract:
A unique cooperative H2 activation reaction by heterobimetallic (NHC)M'-MCp(CO)2 complexes (NHC = N-heterocyclic carbene, M' = Cu or Ag, M = Fe or Ru) has been leveraged to develop a catalytic alkyne semi-hydrogenation transformation. The optimal Ag-Ru catalyst gives high selectivity for converting alkynes to E-alkenes, a rare selectivity mode for reduction reactions with H2. The transformation is tolerant of many reducible functional groups. Computational analysis of H2 activation thermodynamics guided rational catalyst development. Bimetallic alkyne hydrogenation and alkene isomerization mechanisms are proposed.
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