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CO/CO and NO/NO coupling at a hidden frustrated Lewis pair template.

ABSTRACT: N-Allyltetramethylpiperidine is readily isomerized to the corresponding enamine by treatment with catalytic amounts of B(C₆F₅)₃. It adds HB(C₆F₅)₂ at the nucleophilic enamine carbon atom to form a C/B Lewis adduct. This reacts with two molar equivalents of carbon monoxide by selective head to tail coupling to give a five-membered C₂O₂B heterocycle. In contrast the enamine/HB(C₆F₅)₂ Lewis pair reacts with two molar equiv. of nitric oxide by head to head coupling. This reaction probably proceeds via equilibrium with the corresponding vicinal N/B Lewis pair. Most products were characterized by X-ray diffraction.

SUBMITTER: Wang T

PROVIDER: S-EPMC5369402 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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CO/CO and NO/NO coupling at a hidden frustrated Lewis pair template.

Wang Tongdao T Wang Long L Daniliuc Constantin G CG Samigullin Kamil K Wagner Matthias M Kehr Gerald G Erker Gerhard G

Chemical science 20170104 3

N-Allyltetramethylpiperidine is readily isomerized to the corresponding enamine by treatment with catalytic amounts of B(C6F5)3. It adds HB(C6F5)2 at the nucleophilic enamine carbon atom to form a C/B Lewis adduct. This reacts with two molar equivalents of carbon monoxide by selective head to tail coupling to give a five-membered C2O2B heterocycle. In contrast the enamine/HB(C6F5) ...[more]

PMID: 28451352

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