A variety of arenes, including anilines, pyrroles, indoles, aminooxazoles, aminothiazoles, aminoquinolines, and aminopyridines, underwent regioselective Friedel−Crafts alkylation in neat hexafluoroacetone sesquihydrate in a broad range of temperatures, reaction times, and yields (2%−94%) depending strongly on the electron density of the substrate. Prior N,N-dibenzylation of aniline and 2-aminopyridine

Regioselective Friedel-Crafts Alkylation of Anilines and Amino-Substituted Heteroarenes with Hexafluoroacetone Sesquihydrate. -The alkylation of anilines takes place regioselectively at the para position, and heteroarenes are attacked at the position β to the sp 2 -hybridized N-atom. Yields strongly depend on the electron density of the substrates. -(MASCIADRI*, R.; KAMER, M.; NOCK, N.; Eur.