反应详情

Sodium triacetoxyborohydride (396 mg, 1.87 mmol) was added portionwise to ethyl 5-(1,4-diazepan-1-yl)thiophene-2-carboxylate (190 mg, 0.75 mmol) and acetic acid (0.086 ml, 1.49 mmol) in acetone (1.917 ml) at room temperature. The resulting solution was stirred at ambient temperature for 18 h under nitrogen. The reaction mixture was concentrated and diluted with water (200 mL) and basified with 2M NaOH. The aqueous was extracted with diethyl ether (3×100 mL) and washed sequentially with water (200 mL) and saturated brine (200 mL). The organic layer was dried over MgSO4, filtered and evaporated to afford desired product ethyl 5-(4-isopropyl-1,4-diazepan-1-yl)thiophene-2-carboxylate (181 mg, 82%). This was used directly with no further purification.

1. concentrationThe reaction mixture was concentrated
2. additiondiluted with water (200 mL)
3. extractionThe aqueous was extracted with diethyl ether (3×100 mL)
4. washwashed sequentially with water (200 mL) and saturated brine (200 mL)
5. dry with materialThe organic layer was dried over MgSO4
6. filtrationfiltered
7. customevaporated