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Updated: Apr 7, 2026

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Difluoromethylation of Terminal Alkynes by Fluoroform
Satoshi Okusu1, Etsuko Tokunaga1, Norio Shibata1
1†Department of Frontier Materials and ‡Department of Nanopharmaceutical Sciences, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan.
Abstract:
The difluoromethylation of terminal alkynes through the use of fluoroform as a source of difluorocarbene is described. The choice of solvents and bases was found to be crucial for the transformation. A series of terminal alkynes 1 were nicely converted into the corresponding difluoromethyl alkynes 2 using potassium tert-butoxide in n-decane in moderate to good yields. Functional groups such as methoxy, dimethylamino, and bromo as well as phenyl, heteroaryl, and sterically demanding naphthyl were well tolerated under the reaction conditions. One-step transformations of difluoromethyl alkynes 2 to difluoromethylated isoxazoles 3 and 1,2,3-triazoles 4 were also achieved.
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