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Two Faces of the Bi-O Bond: Photochemically and Thermally Induced Dehydrocoupling for Si-O Bond Formation.

ABSTRACT: The diorgano(bismuth)alcoholate [Bi((C₆H₄CH₂)₂S)OPh] (1-OPh) has been synthesized and fully characterized. Stoichiometric reactions, UV/Vis spectroscopy, and (TD-)DFT calculations suggest its susceptibility to homolytic and heterolytic Bi-O bond cleavage under given reaction conditions. Using the dehydrocoupling of silanes with either TEMPO or phenol as model reactions, the catalytic competency of 1-OPh has been investigated (TEMPO=(tetramethyl-piperidin-1-yl)-oxyl). Different reaction pathways can deliberately be addressed by applying photochemical or thermal reaction conditions and by choosing radical or closed-shell substrates (TEMPO vs. phenol). Applied analytical techniques include NMR, UV/Vis, and EPR spectroscopy, mass spectrometry, single-crystal X-ray diffraction analysis, and (TD)-DFT calculations.

SUBMITTER: Ramler J

PROVIDER: S-EPMC9300068 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Two Faces of the Bi-O Bond: Photochemically and Thermally Induced Dehydrocoupling for Si-O Bond Formation.

Ramler Jacqueline J Schwarzmann Johannes J Stoy Andreas A Lichtenberg Crispin C

European journal of inorganic chemistry 20211218 7

The diorgano(bismuth)alcoholate [Bi((C6H4CH2)2S)OPh] (1-OPh) has been synthesized and fully characterized. Stoichiometric reactions, UV/Vis spectroscopy, and (TD-)DFT calculations suggest its susceptibility to homolytic and heterolytic Bi-O bond cleavage under given reaction conditions. Using the dehydrocoupling of silanes with either TEMPO or phenol as model reactions, the catalytic competency of 1-OPh has been investigated (TEMPO=(tetra ...[more]

PMID: 35873275

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