Firstly, triarylmethanes bearing formyl groups (TRAM-CHOs) have been synthesized by the reaction of arenes with aromatic dialdehydes catalyzed by sulfuric acid immobilized on SiO₂ under solvent-free grinding conditions in good yields and short grinding time. Secondly, condensation of TRAM-CHOs with several arenes proceeded rapidly within a few minutes to afford the new corresponding mixed-bistriarylmethanes in excellent yields. TRAM-CHOs were also found to be valuable precursors for the Biginelli reaction to synthesize a variety of 3,4-dihydropyrimidin-2(1H)-one-triarylmethane hybrid derivatives.