Acrylate esters of seven n‐1,1‐dihydroperfluoroalkanols have been synthesized. The esters are: 1,1‐dihydroperfluoroethyl‐; 1,1‐dihydroperfluoropropyl‐; 1,1‐dihydroperfluorobutyl‐; 1,1‐dihydroperfluoropentyl‐; 1,1‐dihydroperfluorohexyl‐; 1,1‐dihydroperfluorooctyl‐; and 1,1‐dihydroperfluorodecyl acrylates. Since these alcohols were difficult to esterify using conventional procedures, acrylyl chloride or acrylic acid plus perfluoroacetic anhydride have been empolyed in this work.

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A series of seven vinyl esters (Table I) has been prepared by the mercury catalyzed reaction of perfluoromonocarboxylic acids with acetylene.' Certain physical properties are given.The reaction of acetylene with carboxylic acids was first studied by Klatte,2 the products being vinyl and ethylidene esters. The usual catalyst for such a liquid phase synthesis of vinyl esters of carboxylic acids is one prepared from mercury and a strong inorganic acid such as sulfuric acid.3Vinyl trifluoroacetate has been prepared by Howk and Jacobson4 and by Dickey and Stanins using liquid phase reactions. Coover, Stanin, and Dickey6 prepared this monomer in the vapor phase. Howk and Jacobson prepared their catalyst from mercuric oxide and sulfuric acid; Dickey and Stanin utilized mercuric oxide and oleum. Coover, Stanin, and Dickey used either zinc oxide or cadmium oxide to catalyze the vapor phase reaction of acetylene and trifluoroacetic acid.In the present nork, which involved liquid phase reactions at atmospheric pressure, several catalyst combinations were tried. Use of a catalyst prepared according to the procedure of Howk and Jacobson did not give satisfactory yields (less than 10%) of the higher vinyl esters. Yields of the order of 20 to 50% were obtained using a complex catalyst prepared from acetylene and fuming sulfuric acid which was in turn reacted with mercuric oxide.7It is known that a trace of water has a deleterious effect upon the vinylation of carboxylic acids.7 Therefore, phosphorus pentoxide was added to the reaction mixture containing the mercuric salt of the perfluoro acid with encouraging results. Using such a procedure, it was possible to obtain yields of vinyl esters (based on the acids) in excess of 70%. However, the addition of phosphorus pentoxide caused the formation of an undesirable solid precipitate in the reaction mixture. Therefore, the perfluoro acid anhydride was substituted for phosphorus pentoxide to give the most generally satisfactory reaction mixture which we have used. Since the perfluoro acids are strong acids, the addition of inorganic acids was unnecessary. Using the mercuric salt of the perfluoro acid plus suficient per-