Synthesis of 2-methyl-1,5-dinitro-3- and 2-methyl-1,3-dinitro-5-(trifluoromethyl)benzenes and their transformation into 6-nitro-4-(trifluoromethyl)- and 4-nitro-6-(trifluoromethyl)-1H-indoles

Abstract A facile two-step synthesis of 2-methyl-1,5-dinitro-3- and 2-methyl-1,3-dinitro-5-(trifluoromethyl)benzenes is described. The first step is the nitration of otho- and para -methylbenzoic acids to furnish the corresponding dinitroacids. The dinitroacids then react with sulfur tetrafluoride to provide the corresponding trifluoromethylated products. The latter are easily transformed into 6-nitro-4-(trifluoromethyl)- and 4-nitro-6-(trifluoromethyl)-1 H -indoles by applying the Batcho–Leimgruber synthetic protocol.