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Geminal bis-borane formation by borane Lewis acid induced cyclopropyl rearrangement and its frustrated Lewis pair reaction with carbon dioxide.

ABSTRACT: Cyclopropylacetylene reacts with two molar equivalents of Piers' borane [HB(C₆F₅)₂] under mild conditions by an addition/rearrangement sequence with cyclopropyl ring opening to give a mixture of two α-B(C₆F₅)₂ substituted tetrahydroboroles. This compound forms an active frustrated Lewis pair with P ^t Bu₃ that heterolytically splits dihydrogen and adds carbon dioxide as a geminal chelate bis-boryl component. The respective reactions of the two-fold HB(C₆F₅)₂ addition to Ph-CH₂CH₂C[triple bond, length as m-dash]CH were studied as a geminal Lewis acid reference. Most of the products were characterized by X-ray diffraction.

SUBMITTER: Liu YL

PROVIDER: S-EPMC5369401 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Geminal bis-borane formation by borane Lewis acid induced cyclopropyl rearrangement and its frustrated Lewis pair reaction with carbon dioxide.

Liu Yun-Lin YL Kehr Gerald G Daniliuc Constantin G CG Erker Gerhard G

Chemical science 20160916 2

Cyclopropylacetylene reacts with two molar equivalents of Piers' borane [HB(C6F5)2] under mild conditions by an addition/rearrangement sequence with cyclopropyl ring opening to give a mixture of two α-B(C6F5)2 substituted tetrahydroboroles. This compound forms an active frustrated Lewis pair with P t Bu3 that heterolytically splits dihydrogen and adds carbon dioxide as a geminal chelate bis-boryl compo ...[more]

PMID: 28451249

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