实验操作An inert reactor was charged with 11·TsOH (32.9 kg, 1.0 equiv), pTsOH·H2O (7.2 kg, 0.8 equiv), and i-PrOH (180 kg, L). The reactor was inerted, and the mixture was agitated at 60 °C for 20 h. To the reactor was charged 12·TsOH (0.2 kg, 0.05 wt %), and the mixture was aged for 1 h. The mixture was cooled to 20 °C over 4 h and then filtered. The filter cake was washed with i-PrOH (79 kg, L) and then dried under vacuum at 40 °C to yield 12·TsOH as a white crystalline solid (23.2 kg, 85.1% yield, 99.0% purity, 95.1% assay purity)
