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Updated: Jun 7, 2025

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Synthesis of α-Boryl-α-Substituted Allylboronates from Propyne
Hiro Takayanagi1, Naoki Oku1,2, Ken Yamazaki1
1Division of Applied Chemistry, Okayama University, Tsushimanaka, Okayama 700-8530, Japan.
Abstract:
A novel method for the two-step synthesis of α-boryl-α-substituted allylboronates from propyne is described. These allylboronates are prepared by the Co-catalyzed 1,1-diboration reaction of propyne with B2pin2, followed by the base-mediated alkylation reaction of 1,1-di(boryl)propene at the α-position. Computational studies revealed the origins of observed reactivity and selectivity in the base-mediated alkylation reaction. The resulting α-boryl-α-methyl-allylboronate is applied to the allylation of aldehydes, which gives homoallylic alcohols with a trisubstituted alkene moiety.
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