Iridium-catalyzed dehydrogenation of substituted amine boranes: kinetics, thermodynamics, and implications for
Brandon L Dietrich1, Karen I Goldberg, D Michael Heinekey
1Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, USA.
Abstract:
Dehydrogenation of amine boranes is catalyzed efficiently by the iridium pincer complex (kappa (3)-1,3-(OP ( t )Bu 2) 2C 6H 3)Ir(H) 2 ( 1). With CH 3NH 2BH 3 (MeAB) and with AB/MeAB mixtures (AB = NH 3BH 3), the rapid release of 1 equiv of H 2 is observed to yield soluble oligomeric products at rates similar to those previously reported for the dehydrogenation of AB catalyzed by 1. Delta H for the dehydrogenation of AB, MeAB, and AB/MeAB mixtures has been determined by calorimetry. The experimental heats of reaction are compared to results from computational studies.
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