反应详情

Isopropylamine (1.2 g, 20.3 mmol) and 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU, 6 mL) are added to a solution of 2-dimethylamino-4-trifluoromethyl-6H-1,3-oxazin-6-one (4.0 g, 19.2 mmol) in xylene (34 mL). The resultant reaction mixture is held at 100° C. for 3 hours, cooled, washed with 5 wt. % HCl (40 mL), and extracted with ethyl acetate. The combined organic extracts are concentrated and triturated with heptane. The solids are filtered and dried to give the title product as a yellow powder (2.3 g, 54% yield, mp 127°-129° C.) which is identified by 1H NMR (DMSO-d6) δ6.11 (1H, s), 4.96 (1H, sp), 1.35 (6H, d); and 19F NMR δ−68.9 (s).

1. customThe resultant reaction mixture
2. temperaturecooled
3. washwashed with 5 wt. % HCl (40 mL)
4. extractionextracted with ethyl acetate
5. concentrationThe combined organic extracts are concentrated
6. customtriturated with heptane
7. filtrationThe solids are filtered
8. customdried