反应详情

A solution of butyl lithium in hexane (2.7M, 104 ml) was added slowly to a stirred solution of 1,5-dimethyltetrazole (27.5 g) in dry tetrahydrofuran (500 ml) at -5° to 0° under nitrogen. After stirring for 1.5 hours, 7-bromo-1H-3,1-benzoxazine-2,4-dione (22.6 g) was added and stirring continued for 18 hours at room temperature and for 3.5 hours at 40° to 50°. The mixture was cooled to room temperature, industrial methylated spirit (15 ml) added and most of the solvents distilled off. The residue was added to water (200 ml) and acidified with 5N hydrochloric acid to pH 1. The resulting solid was collected by filtration and crystallised from ethyl acetate to give the novel compound 1-(2-amino-4-bromophenyl)-2-(1-methyl-1H-tetrazol-5-yl)ethanone, m.p. 159°-160°.

1. stirringstirring
2. waitcontinued for 18 hours at room temperature and for 3.5 hours at 40° to 50°
3. distillationdistilled off
4. additionThe residue was added to water (200 ml)
5. filtrationThe resulting solid was collected by filtration
6. customcrystallised from ethyl acetate