反应详情

tert-Butyl-chloro-silane (0.25 ml) was added to a mixture of 2-bromo-4-methoxy-6-nitro-phenol (0.124 g), chromium (II) chloride (0.012 g) and manganese (0) powder (0.137 g) in dimethylformamide (3 mL). The mixture was subjected to microwaves for 4 min at 150° C. Benzaldehyde (0.06 mL) was added and the reaction was subjected to microwaves for 6 min at 150° C. Water (0.5 mL) was added, then after 30 min the mixture was filtered through a pad of celite. The above procedure was repeated three more times. The combined filtrate was partitioned between dilute aq. HCl (100 mL) and ethyl acetate (100 mL). The organic layer was dried over sodium sulfate, filtered through celite and concentrated. Chromatography on silica gel (eluant: gradient 0 to 30% ethyl acetate:hexane) afforded 7-bromo-5-methoxy-2-phenyl-benzooxazole (0.13 g). MS: 304 (95%), 306.4 (100%) (MH+); HPLC tR: 2.79 min.

1. waitthe reaction was subjected to microwaves for 6 min at 150° C
2. filtrationafter 30 min the mixture was filtered through a pad of celite
3. customThe combined filtrate was partitioned between dilute aq. HCl (100 mL) and ethyl acetate (100 mL)
4. dry with materialThe organic layer was dried over sodium sulfate
5. filtrationfiltered through celite and
6. concentrationconcentrated