反应详情

To a solution of intermediate from step B (484 mg, 2.51 mmol) in 17 mL anhydrous methylene chloride cooled to 0° C. was added N,O-dimethylhydroxylamine hydrochloride (368 mg, 3.77 mmol) followed by pyridine (0.61 mL, 7.54 mmol). The reaction was warmed to room temperature and stirred overnight after which it was quenched with water. The aqueous layer was extracted with methylene chloride (2×) and the combined organic layers were dried over anhydrous MgSO4, filtered and concentrated in vacuo. The resulting oil was purified by flash column chromatography using 40% EtOAc/Hexanes to give the product as a colorless oil. 1H NMR (CDCl3, 500 MHz): 3.45 (d, J=2.5 Hz, 3H), 3.59 (d, J=2.5 Hz, 3H), 8.05 (m, 1H), 8.15 (dd, J=8.7, 3.2 Hz, 1H), 8.46 (d, J=1.8 Hz, 1H), 8.91 (d, J=2.5, 2H). LC-MS: 1.11 min. (M+H)=111.

1. customwas quenched with water
2. extractionThe aqueous layer was extracted with methylene chloride (2×)
3. dry with materialthe combined organic layers were dried over anhydrous MgSO4
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe resulting oil was purified by flash column chromatography