Regioselectively fluoro-, trifluoromethyl-and trifluoromethoxy-substituted 3- methyleneindolines have been prepared using a four-step procedure involving metalation/ bromination of fluorinated Boc-protected anilines, N-propargylation of the resulting o- bromoarylcarbamate and reductive radical cyclization of the product with tributyltin hydride/AIBN. 3-Methyleneindolines, as valuable, versatile intermediates, can be ...