反应详情

A stirred mixture of the crude product from step (i) and guanidine carbonate (128.1 g) in methanol (915 mL) was heated under reflux for 5 hours. The mixture was cooled to room temperature, diluted with water (923 mL) and nuetralised with acetic acid. The mixture was then cooled to 10° C. and the resulting precipitate collected by filtration, washed with methanol (501 mL) and dried under reduced pressure to give the subtitle compound as a solid, 82.4 g; 1H NMR DMSO-d6: δ 10.91 (brs, 1H), 7.20-7.17 (m, 4H), 6.38 (s, 2H), 3.95 (s, 2H), 3.63 (s, 2H), 2.00 (s, 3H).

1. temperaturewas heated
2. temperatureunder reflux for 5 hours
3. temperatureThe mixture was then cooled to 10° C.
4. filtrationthe resulting precipitate collected by filtration
5. washwashed with methanol (501 mL)
6. customdried under reduced pressure