反应详情

A solution of the alcohol (50 g, 0.13 moles) produced in Example 22 and pyridine (10.7 ml, 0.13 moles) in 500 ml of methylene chloride was added dropwise under nitrogen to a solution of 4-nitrophenyl chloroformate (26.64 g, 0.13 mol) in 500 ml of methylene chloride at room temperature. After the addition, the reaction was stirred overnight at room temperature. A solid had formed which was removed by filtration. The filtrate was extracted two times with 1N HCl, multiple times with saturated Na2CO3, dried (MgSO4) and the solvent removed under reduced pressure. Recrystallization of the crude reaction product from hexane gave 27.9 g (39%) of the title compound as a light yellow crystalline solid, mp 78-80° C.

1. additionAfter the addition
2. customA solid had formed which
3. customwas removed by filtration
4. extractionThe filtrate was extracted two times with 1N HCl, multiple times with saturated Na2CO3
5. dry with materialdried (MgSO4)
6. customthe solvent removed under reduced pressure
7. customRecrystallization of the crude
8. customreaction product from hexane