Molybdenum Catalyzed Ammonia Borane Dehydrogenation: Oxidation State Specific Mechanisms
نویسندگان
چکیده
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.
منابع مشابه
Correction to Molybdenum Catalyzed Ammonia Borane Dehydrogenation: Oxidation State Specific Mechanisms
Experimental Details S3 General Considerations S3 Synthesis of 2 S3 Synthesis of 3 S4 Synthesis of 4 S4 Synthesis of 5 S5 Synthesis of 6 S6 Synthesis of 6-HD S6 Synthesis of 7 S6 Synthesis of 8 S7 Reaction of 8 with D2 S7 Reactivity with AB Analogs S7 Time Resolved AB Dehydrogenation Experiments S8 NH2BH2 Trapping Experiments S8 Eudiometric Measurement Details S8 Figure S1—Eudiometer Diagram S9...
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