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Updated: Jun 7, 2025

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
Zinc borylation and reduction by a diborane(4) species via B-O bond formation
Liam P Griffin1, Simon Aldridge1
1Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford South Parks Road Oxford OX1 3QR UK simon.aldridge@chem.ox.ac.uk.
Abstract:
We report a convenient synthesis of the zinc-boryl complex (NacnacMes)ZnBpin under mild conditions via formal disproportionation of bis(pinacolato)diboron(4), aided thermodynamically by B-O bond formation. This species can be isolated both base-free and as the DMAP adduct (NacnacMes)Zn(DMAP)Bpin and crystallographically characterised in the latter form. Onward reactivity of the base free zinc boryl complex with CO2 occurs reductively, yielding further B-O bonds as well as CO gas. The strength of this driving force can then be harnessed in the reaction between (NacnacMes)ZnBpin and a Zn-O bonded species (NacnacMes)ZnOB{(NDippCH)2}, which yields the metal-metal bonded dimer [(NacnacMes)Zn]2, the overall formation of which utilizes a diboron(4) species as the stoichiometric reductant of Zn(ii) to Zn(i).
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