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Oxidation, Coordination, and Nickel-Mediated Deconstruction of a Highly Electron-Rich Diboron Analogue of 1,3,5-Hexatriene.

ABSTRACT: The reductive coupling of an N-heterocyclic carbene (NHC) stabilized (dibromo)vinylborane yields a 1,2-divinyldiborene, which, although isoelectronic to a 1,3,5-triene, displays no extended ? conjugation because of twisting of the C2 B2 C2 chain. While this divinyldiborene coordinates to copper(I) and platinum(0) in an ?2 -B2 and ?4 -C2 B2 fashion, respectively, it undergoes a complex rearrangement to an ?4 -1,3-diborete upon complexation with nickel(0).

SUBMITTER: Hermann A

PROVIDER: S-EPMC7497145 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Oxidation, Coordination, and Nickel-Mediated Deconstruction of a Highly Electron-Rich Diboron Analogue of 1,3,5-Hexatriene.

Hermann Alexander A Fantuzzi Felipe F Arrowsmith Merle M Zorn Theresa T Krummenacher Ivo I Ritschel Benedikt B Radacki Krzysztof K Engels Bernd B Braunschweig Holger H

Angewandte Chemie (International ed. in English) 20200701 36

The reductive coupling of an N-heterocyclic carbene (NHC) stabilized (dibromo)vinylborane yields a 1,2-divinyldiborene, which, although isoelectronic to a 1,3,5-triene, displays no extended π conjugation because of twisting of the C2 B2 C2 chain. While this divinyldiborene coordinates to copper(I) and platinum(0) in an η2 -B2 and η4 -C2 B2 fashion, respectively, it undergoes a complex rearrangement to an η<su ...[more]

PMID: 32449598

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