Short-RInChIKey=SA-FUHFF-UHFFFADPSC-PEQHIRFAKI-UHFFFADPSC-NUHFF-NUHFF-NUHFF-ZZZ

In a 500 mL round bottom flask,4-tritylaniline hydrochloride (23.2 g, 62.3 mmol, 1.00 equiv) was suspended in 235 mL of N,N-dimethylformamide and cooled to -15 °C. At this temperature, sulfuric acid (36.7 g, 19.9 mL, 374 mmol, 6.00 equiv) and isoamylnitrit (14.9 g, 17.0 mL, 127 mmol, 2.04 equiv) were added. The reaction mixture was stirred for 1 hour at this temperature and then phosphinic acid (20.6 g, 17.0 mL, 311 mmol, 5.00 equiv) was added carefully. The reaction mixture was then heated to 50 °C until no further gas evolution was observed (around 4 hours). The resulting solid was filtered off and washed twice with 250 mL of N,N-dimethylformamide, 250 mL water and 250 mL ethanol to give tetraphenylmenthan (15.7 g, 49.0 mmol, quant.) as a brownish solid.