反应详情

To a solution of intermediate 58 (164 mg, 1.0 mmol) in chlorobenzene (5 mL) was added bis(2-chloroethyl)amine hydrochloric acid (285 mg, 1.6 mmol) and the mixture was heated to reflux for 100 h. The reaction mixture was concentrated in vacuo and the residue was stirred in EtOAc for 2 h. The resulting brown solid was filtered and purified by silica gel chromatography to give 8-(piperazin-1-yl)-2H-benzo[b][1,4]oxazin-3(4H)-one (intermediate 59) (150 mg, 64%). HPLC: 99%, RT 1.344 min. MS (ESI) m/z 234.1[M+H]+.

1. temperaturethe mixture was heated
2. temperatureto reflux for 100 h
3. concentrationThe reaction mixture was concentrated in vacuo
4. filtrationThe resulting brown solid was filtered
5. custompurified by silica gel chromatography