Nitration of mesitylene and difluoromesitylene in anhydrous hydrofluoric acid gave near quantitative yields of dinitromesitylene and 2,4-difluoro-6-nitromesitylene, respectively. Difluoro- and trifluoromesitylene were synthesized by the Schiemann reaction in record yields reported for this type of reaction. Various intermediates and derivatives are reported for the fluoromesitylenes. Among the products of exhaustive chlorination of trifluoromesitylene, 2,4,6-tris-(trichloromethyl)-1,-3,5-trifluorobenzene and 2,4,6-trichloro-1,3,5-trifluorobenzene were identified.