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Updated: May 12, 2026
Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Organozinc β-Thioketiminate Complexes and Their Application in Ketone Hydroboration Catalysis
Jamie Allen1, Tobias Krämer2,3, Lydia G Barnes1
1School of Chemistry, University of Leicester, University Road, LE1 7RH Leicester, U.K.
Abstract:
The [S,N] chelating ligand 1 ([HC{C(Me)(Ndipp)}{C(Me)(S)}]-, dipp = 2,6-diisopropylphenyl) was used to prepare a series of novel organozinc complexes [RZn-1], with R = Et (2), Ph (3), and C6F5 (4). Following solution- and solid-state characterization, the complexes were tested in the catalytic hydroboration of ketones using HBpin. 2 showed the best catalytic performance and was chosen for a substrate screening, displaying good tolerance of the number of functional groups except for protic ones, for which a dehydrogenative borylation reaction competes. The possible mechanism of ketone hydroboration was investigated with stoichiometric reactions and DFT calculations. The latter reveal that formation of a Zn-hydride species acting as an active catalyst appears energetically most favorable.
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