反应详情

13.4 g (0.1 mol) of benzimidazolone are reacted with 50.2 g (0.24 mol) of methyl 6-bromohexanoate in a solvent mixture of 100 ml of dimethylformamide and 100 ml of benzene, 15.2 g of dry potassium carbonate powder being used as the acid acceptor. The reaction is carried out at 98°-99° C., whilst stirring well, the water formed during the reaction being removed azeotropically. Thereafter, the hot reaction mixture is filtered and the filtrate is concentrated to dryness. A yellowish oil (39.0 g), which completely crystallises on standing, is obtained in quantitative yield. The purification can be carried out in the customary manner. The product thus prepared shows a proton magnetic resonance spectrum which agrees with the following structure: ##STR20##

1. customis carried out at 98°-99° C.
2. custombeing removed azeotropically
3. filtrationThereafter, the hot reaction mixture is filtered
4. concentrationthe filtrate is concentrated to dryness
5. customA yellowish oil (39.0 g), which completely crystallises on standing
6. customis obtained in quantitative yield
7. customThe purification