反应详情

To 1,1-dimethylethyl 4-(methylsulfonyl)-1-piperazinecarboxylate (360 g, 1.36 mol) in MeOH (1 L) was added HCl (6 M in MeOH, 2 L) dropwise. The mixture was stirred at rt for 1 h. About 1 L of MeOH was rotovapped off. The resultant precipitate was filtered, washed with MeOH, and dried on high vacuum to provide the title compound of Step B (A combination of 2 batches, 570 g) which was used without further purification. 1H NMR (400 MHz, D2O) δ 2.95 (s, 3H), 3.27-3.29 (m, 4H), 3.42-3.46 (m, 4H).

1. filtrationThe resultant precipitate was filtered
2. washwashed with MeOH
3. customdried on high vacuum