6-benzyloxy-8-(2-chloro-acetyl)-4H-benzo[1,4]oxazin-3-one synthesis

Yield:869478-10-4 86%

Reaction Conditions:

with N,N,N-trimethylbenzenemethanaminium dichloroiodate in 1,1-dichloroethane;water;acetic acid at 65; for 5 h;

Steps:

1.d

13.8 g (46.0 mmol) 8-acetyl-6-benzyloxy-4H-benzo[1,4]oxazin-3-one and 35.3 g (101.5 mmol) benzyltrimethylammonium-dichloriodate are stirred in 250 mL dichloroethane, 84 mL glacial acetic acid and 14 mL water for 5 hours at 65° C. After cooling to ambient temperature the mixture is combined with 5% sodium hydrogen sulphite solution and stirred for 30 minutes. The precipitated solid is suction filtered, washed with water and diethyl ether and dried. Yield: 13.2 g (86%); mass spectroscopy [M+H]⁺=330/32.

References:

US2005/267106,2005,A1 Location in patent:Page/Page column 7