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Updated: Feb 24, 2026
Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Metal-Free Synthesis of Homopropargylic Alcohols from Aldehydes
Bruno V M Teodoro1, Luiz F Silva1
1Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo , São Paulo, SP 05508-000, Brazil.
Abstract:
The synthesis of homopropargylic alcohols under metal-free and mild condition is described. This transformation is based on a one-pot procedure involving sequential α-alkynylation of acyclic aldehydes using hypervalent iodine reagents and borohydride reduction. The chemistry exhibits broad substrate scope and good scalability, providing a convenient route for the α-alkynylation of aldehydes along with the formation of a quaternary carbon center. The applicability of the method is demonstrated by the gram-scale synthesis of the key synthetic precursor of botulinum toxin inhibitors.
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