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It is used as pharmaceutical intermediate. Reactions of aldehydes with triphenylphosphine and sodium chlorodifluoroacetate yield 1,1-difluoro olefins. It is a general reaction and a one step synthesis.
Samuel A. Fuqua.; Warren G. Duncan.; Robert M. Silverstein.Synthesis of 1,1-Difluoro Olefins. II. Reactions of Ketones with Tributylphosphine and Sodium Chlorodifluoroacetate. J. Org. Chem. 1965, 30 (8),2543-2545 .
Samuel A. Fuqua.; Warren G. Duncan.; Robert M. Silverstein.A One-Step Synthesis of 1,1-Difluoro Olefins from Aldehydes. J. Org. Chem. 1965, 30 (4),1027-1029 .
Thermolysis in refluxing diglyme generates difluorocarbene: Proc. Chem. Soc., 81 (1960); Tetrahedron, 25, 1219 (1969); Tetrahedron Lett., 1319 (1973). In triglyme at 165o, gave better results in comparison with most other difluorocarbene precursors in cyclopropanation of an enol ether: Tetrahedron, 46, 5213 (1990).
In the presence of triphenyl- or tributylphosphine, the carbene is intercepted to give the difluoromethylenephosphorane, which can be used to convert aldehydes and ketones to 1,1-difluoroalkenes: Tetrahedron Lett., 1461 (1964); J. Org. Chem., 30, 1027, 2543 (1965); Org. Synth. Coll., 5, 390, 949 (1973):
Dichiarazioni di rischio (UE): H315-H319-H335
Causes skin irritation. Causes serious eye irritation. May cause respiratory irritation.
Dichiarazioni precauzionali: P261-P280a-P305+P351+P338-P304+P340-P405-P501a
Avoid breathing dust/fume/gas/mist/vapours/spray. Wear protective gloves and eye/face protection. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. IF INHALED: Remove to fresh air and keep at rest in a position comfortable for breathing. Store locked up. Dispose of contents/container in accordance with local/regional/national/international regulations.