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Magnesocenophane-Catalyzed Amine Borane Dehydrocoupling.

ABSTRACT: The Lewis acidities of a series of [n]magnesocenophanes (1?a-d) have been investigated computationally and found to be a function of the tilt of the cyclopentadienyl moieties. Their catalytic abilities in amine borane dehydrogenation/dehydrocoupling reactions have been probed, and C[1]magnesocenophane (1?a) has been shown to effectively catalyze the dehydrogenation/dehydrocoupling of dimethylamine borane (2?a) and diisopropylamine borane (2?b) under ambient conditions. Furthermore, the mechanism of the reaction with 2?a has been investigated experimentally and computationally, and the results imply a ligand-assisted mechanism involving stepwise proton and hydride transfer, with dimethylaminoborane as the key intermediate.

SUBMITTER: Wirtz L

PROVIDER: S-EPMC7318289 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Magnesocenophane-Catalyzed Amine Borane Dehydrocoupling.

Wirtz Lisa L Haider Wasim W Huch Volker V Zimmer Michael M Schäfer André A

Chemistry (Weinheim an der Bergstrasse, Germany) 20200428 28

The Lewis acidities of a series of [n]magnesocenophanes (1 a-d) have been investigated computationally and found to be a function of the tilt of the cyclopentadienyl moieties. Their catalytic abilities in amine borane dehydrogenation/dehydrocoupling reactions have been probed, and C[1]magnesocenophane (1 a) has been shown to effectively catalyze the dehydrogenation/dehydrocoupling of dimethylamine borane (2 a) and diisopropylamine borane (2 b) under ambient conditions. Furthermore, the mechanism ...[more]

PMID: 32052880

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