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Updated: Jun 17, 2026
Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Synthesis of dialkyl ethers from organotrifluoroborates and acetals
T Andrew Mitchell1, Jeffrey W Bode
1Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA.
Abstract:
The formation of ethers by C-O bond formation under harsh basic or acidic conditions is an entrenched synthetic disconnection in organic chemistry. We report a strategic alternative that involves the BF(3).OEt(2)-promoted coupling of stable, easily prepared acetals with widely available potassium aryl-, alkenyl-, and alkynyltrifluoroborates. This fast, operationally simple process offers straightforward access to dialkyl ethers, many of which would be difficult to prepare using classical methods. The use of MOM-protected alcohols and acetal-protected aldehydes enables ether formation without recourse to protecting-group manipulations or strong bases.
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