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Molybdenum catalyzed ammonia borane dehydrogenation: oxidation state specific mechanisms.

ABSTRACT: Though numerous catalysts for the dehydrogenation of ammonia borane (AB) are known, those that release >2 equiv of H2 are uncommon. Herein, we report the synthesis of Mo complexes supported by a para-terphenyl diphosphine ligand, 1, displaying metal-arene interactions. Both a Mo(0) N2 complex, 5, and a Mo(II) bis(acetonitrile) complex, 4, exhibit high levels of AB dehydrogenation, releasing over 2.0 equiv of H2. The reaction rate, extent of dehydrogenation, and reaction mechanism vary as a function of the precatalyst oxidation state. Several Mo hydrides (Mo(II)(H)2, [Mo(II)(H)](+), and [Mo(IV)(H)3](+)) relevant to AB chemistry were characterized.

SUBMITTER: Buss JA

PROVIDER: S-EPMC4140452 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Molybdenum catalyzed ammonia borane dehydrogenation: oxidation state specific mechanisms.

Buss Joshua A JA Edouard Guy A GA Cheng Christine C Shi Jade J Agapie Theodor T

Journal of the American Chemical Society 20140730 32

Though numerous catalysts for the dehydrogenation of ammonia borane (AB) are known, those that release >2 equiv of H2 are uncommon. Herein, we report the synthesis of Mo complexes supported by a para-terphenyl diphosphine ligand, 1, displaying metal-arene interactions. Both a Mo(0) N2 complex, 5, and a Mo(II) bis(acetonitrile) complex, 4, exhibit high levels of AB dehydrogenation, releasing over 2.0 equiv of H2. The reaction rate, extent of dehydrogenation, and reaction mechanism vary as a funct ...[more]

PMID: 25034459

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Correction to Molybdenum catalyzed ammonia borane dehydrogenation: oxidation state specific mechanisms.

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