反应详情

A suspension of 5.8 g (0.020 mol) of 8-fluoro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxamidoxime in 60 ml of dimethylformamide was treated with 3.9 g (0.023 mol) of chloroacetic anhydride. The yellow solution obtained was stirred at 100° for 11/2 hr. and then completely freed from solvents. The oily product crystallized from acetonitrile and was filtered off. The mother liquor was concentrated, the residue was chromatographed over silica gel with dichloromethane/methanol 97:3 as the eluent and the additional portion of product obtained was recrystallized from acetonitrile. There were obtained a total of 4.05 g (59%) of 3-(5-chloromethyl-1,2,4-oxadiazol-3-yl)-8-fluoro-5-methyl-5,6-dihydro-4H-imidazo[1,5-a][1,4]benzodiazepin-6-one as white crystals; m.p. 245°-247°.

1. customThe yellow solution obtained
2. customThe oily product crystallized from acetonitrile
3. filtrationwas filtered off
4. concentrationThe mother liquor was concentrated
5. customthe residue was chromatographed over silica gel with dichloromethane/methanol 97:3 as the eluent
6. customthe additional portion of product obtained
7. customwas recrystallized from acetonitrile