反应详情

To a stirred solution of Step 2 intermediate (16.5 g, 94.82 mmol) in dry THF (316 ml) was added triphosgene (14.07 g, 47.41 mmol) and the mixture was refluxed for overnight under nitrogen atmosphere. The mixture was cooled to room temperature and diluted with water (200 ml) under stirring. The solid precipitated out was collected by filtration and dried to give 13.8 g of the desired product; 1H NMR (300 MHz, DMSO-d6) δ 2.36 (s, 3H), 6.82 (s, 1H), 11.07 (br. s, 1H), 11.79 (br. s, 1H).

1. temperaturethe mixture was refluxed for overnight under nitrogen atmosphere
2. customThe solid precipitated out
3. filtrationwas collected by filtration
4. customdried