title: P-C-Activated Bimetallic Rhodium Xantphos Complexes: Formation and Catalytic Dehydrocoupling of Amine-Boranes.
abstract: {Rh(xantphos)}-based phosphido dimers form by P-C activation of xantphos (4,5-bis(diphenylphosphino)-9,9-dimethylxanthene) in the presence of amine-boranes. These dimers are active dehydrocoupling catalysts, forming polymeric [H2 BNMeH]n from H3 B⋅NMeH2 and dimeric [H2 BNMe2 ]2 from H3 B⋅NMe2 H at low catalyst loadings (0.1 mol %). Mechanistic investigations support a dimeric active species, suggesting that bimetallic catalysis may be possible in amine-borane dehydropolymerization.
authors.affiliation: Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA (UK).
authors.forename: Heather C
authors.initials: HC
authors.lastname: Johnson
authors.affiliation: Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA (UK). andrew.weller@chem.ox.ac.uk.
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Weller
keywords: P ligands; X-ray diffraction; amine-boranes; homogeneous catalysis; rhodium