P–C-Activated Bimetallic Rhodium Xantphos Complexes: Formation and Catalytic Dehydrocoupling of Amine–Boranes**
نویسندگان
چکیده
{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.
منابع مشابه
Catalytic dehydrocoupling of amine-boranes and amines into diaminoboranes: isolation of a Pt(ii), Shimoi-type, η(1)-BH complex.
The platinum complex [Pt(I(t)Bu')(I(t)Bu)][BAr(F)] is a very efficient catalyst in the synthesis of diaminoboranes through dehydrocoupling of amine-boranes and amines. Shimoi-type, η(1)-BH complexes are key intermediates in the process.
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