2-(N-arylimino)-3,3,3-trifluoropropanoic acid esters with a chiral oxazaborolidine catalyst and subsequent oxidative removal of N-aromatic moiety with retention of the configuration. Detailed optimization studies revealed that the effects of solvents, temperature, and the structural modification of the substrate were drastic on the enantioselectivity. The absolute configuration of 1 was determined to be (R) by
converted to trifluoromethylated indoles by the tin-radical promoted homolysis of the carbon–iodine bond followed by intramolecular cyclization. The photolysis of trifluoroacetimidoyl iodides enabled both intra- and intermolecular cyclization to indoles and quinolines. Likewise, thermal reactions of N-(2,2,2-trifluoro-1-tritylazoethylidene)anilines provided trifluoromethylatedquinolines and indoles
Trifluoroacetimidoyl chlorides 1 were obtained in 80-90 % yields when a mixture of trifluoroacetic acid and a primary amine was heated in carbon tetrachloride in the presence of triphenylphosphine and triethylamine. The corresponding bromides 2 were obtained when carbon tetrabromide was used instead of carbon tetrachloride. Imidoyl iodides 3 were prepared by substitution of the chloro group of 1 by iodide ion in acetone.
Homologation of trifluoroacetimidoyl iodides by palladium-catalyzed carbonylation. An approach to α-amino perfluoroalkanoic acids.
Homologation of trinuoroacetimidoyl iodides and the related perfluoro-compounds by palladium-catalyst under CO(1atm)-atmosphere in the presence of alcohols gives alpha-imino perfluoroatkanoates which are transformed to alpha-amino perfluoroalkanoic acids.