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Versatile reactivity of a rhodium(I) boryl complex towards ketones and imines
Sabrina I Kalläne1, Thomas Braun, Beatrice Braun
1Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Straße 2, D-12489 Berlin, Germany. thomas.braun@chemie.hu-berlin.de.
Abstract:
The rhodium(I) boryl complex [Rh(Bpin)(PEt3)3] (1) reacts with the ketones α,α,α-trifluoroacetophenone and 9-fluorenone by insertion of the C=O bond to give [Rh{η(3)-C(CF3)(OBpin)C6H5}(PEt3)2] (4) and [Rh{η(5)-C13H8(OBpin)}(PEt3)2] (6), whereas the reaction with acetophenone leads to the formation of [Rh(H)(PEt3)3] (2), [Rh(OBpin)(PEt3)3] (3) and (E)-(Ph)CH=CHBpin. Treatment 1 of with ketimines generates [Rh{η(3)-C6H5=C(Ph)N(Ph)(Bpin)}(PEt3)2] (7), [Rh{(η(3)-C12H8)N(Ph)(Bpin)}(PEt3)2] (8) or [Rh{CPh2N(H)(Bpin)}(PEt3)2] (9). The insertion of aldimines into the Rh-B bond gives access to [Rh[η(3)-CH{N(C6H13)Bpin}C6H5](PEt3)2] (11) or [Rh[η(3)-CH{N(Ph)Bpin}C6H5](PEt3)2] (12). The latter is converted into the C-H activation product [Rh{(C6H4)-o-N(Bpin)(CH2Ph)}(PEt3)3] (13). Complex 13 reacts with B2pin2 to yield the boryl complex 1 and the amine PhCH2N(Bpin)(C6H4-o-Bpin).
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