反应详情

2-(4-Nitrophenoxy)propionic acid 2-[2-(4-nitrophenoxy)acetoxy]-ethyl ester 38 (20 g, 50 mmol) was dissolved in dry dimethylformamide (150 ml) in a pressure vessel. Palladium on carbon (5%, 5 g) was added and the mixture stirred under an atmos-phere of hydrogen (4 kg) for 3 hrs. The catalyst was removed by filtration and ice water (1 L) added to the filtrate. Crude 39 was extracted into ethyl acetate, dried over Na2SO4, distilled and purified by column chromatography on silica gel using chloroform:ethyl acetate (8:2) to give pure 39 (10 g, 58%) as a dark brown syrup.

1. customThe catalyst was removed by filtration and ice water (1 L)
2. additionadded to the filtrate
3. extractionCrude 39 was extracted into ethyl acetate
4. dry with materialdried over Na2SO4
5. distillationdistilled
6. custompurified by column chromatography on silica gel