Polyfluorocarbanion chemistry. Part IV. Some reactions of 2H- and 1H-pentafluoropropene with nucleophiles

Abstract

2H-Pentafluoropropene reacts with sodium methanethiolate in ether to give cis-1,3,3,3-tetrafluoroprop-1-enyl methyl sulphide; sodium thiophenolate or sodium 1,1-dimethylethanethiolate similarly give mainly the corresponding cis-tetrafluoropropenyl sulphides, but small amounts of the corresponding trans-isomers and the 1,1,3,3-tetrafluoroprop-2-enyl sulphides are also formed. In contrast dimethylamine in ether gives a mixture of NN-dimethyl-1,1,3,3,3-pentafluoropropylamine and trans-NN-dimethyl-1,3,3,3-tetrafluoroprop-1-enylamine. Reaction of the propene with sodium methanethiolate or 1,1-dimethylethanethiolate in the presence of the respective thiols gives mixtures of the three tetrafluoropropenyl alkyl sulphides and the 1,1,3,3,3-pentafluoropropyl alkyl sulphide. 1H-Pentafluoropropene (95%cis-isomer) reacts with sodium methoxide in methanol or m-xylene, sodium methane-thiolate in methanethiol or m-xylene, and dimethylamine to give the corresponding trans-2,3,3,3-tetrafluoroprop-1-enyl compounds as the exclusive products.