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The Simplest Amino-borane H2 B=NH2 Trapped on a Rhodium Dimer: Pre-Catalysts for Amine-Borane Dehydropolymerization.

ABSTRACT: The μ-amino-borane complexes [Rh2 (L(R) )2 (μ-H)(μ-H2 B=NHR')][BAr(F) 4 ] (L(R) =R2 P(CH2 )3 PR2 ; R=Ph, (i) Pr; R'=H, Me) form by addition of H3 B⋅NMeR'H2 to [Rh(L(R) )(η(6) -C6 H5 F)][BAr(F) 4 ]. DFT calculations demonstrate that the amino-borane interacts with the Rh centers through strong Rh-H and Rh-B interactions. Mechanistic investigations show that these dimers can form by a boronium-mediated route, and are pre-catalysts for amine-borane dehydropolymerization, suggesting a possible role for bimetallic motifs in catalysis.

SUBMITTER: Kumar A

PROVIDER: S-EPMC5074255 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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The Simplest Amino-borane H2 B=NH2 Trapped on a Rhodium Dimer: Pre-Catalysts for Amine-Borane Dehydropolymerization.

Kumar Amit A Beattie Nicholas A NA Pike Sebastian D SD Macgregor Stuart A SA Weller Andrew S AS

Angewandte Chemie (International ed. in English) 20160421 23

The μ-amino-borane complexes [Rh2 (L(R) )2 (μ-H)(μ-H2 B=NHR')][BAr(F) 4 ] (L(R) =R2 P(CH2 )3 PR2 ; R=Ph, (i) Pr; R'=H, Me) form by addition of H3 B⋅NMeR'H2 to [Rh(L(R) )(η(6) -C6 H5 F)][BAr(F) 4 ]. DFT calculations demonstrate that the amino-borane interacts with the Rh centers through strong Rh-H and Rh-B interactions. Mechanistic investigations show that these dimers can form by a boronium-mediated route, and are pre-catalysts for amine-borane dehydropolymerization, suggesting a possible role ...[more]

PMID: 27100775

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