反应详情

To a solution of (4-chloro-2-hydroxymethyl-phenyl)-carbamic acid ethyl ester (71) obtained from the previous step in 5 mL of toluene was added 3 mL of DBU (2 equiv) and the resultant solution was heated at 110° C. overnight. After cooling to rt, the mixture was diluted with EtOAc and washed with water. The organic layer was dried over sodium sulfate, filtered and dried in vacuo to give 6-chloro-1,4-dihydro-benzo[d][1,3]oxazin-2-one (72).

1. washwashed with water
2. dry with materialThe organic layer was dried over sodium sulfate
3. filtrationfiltered
4. customdried in vacuo