反应详情

2 M HCl (14 ml) was added to a solution of benzyl 7,7-dimethyl-1,4-dioxaspiro[4.5]decan-8-ylcarbamate (1.4 g, 4.3887 mmol, 1 eq) in MeOH (14 ml), and stirring was carried out for 18 h at RT. The solvent was concentrated under reduced pressure and the residue was diluted with water (10 ml) and rendered basic with sat. sodium hydrogen carbonate solution (20 ml). Then extraction with ethyl acetate (2×50 ml) was carried out. The combined organic phases were washed with water (50 ml) and sat. NaCl solution (50 ml), dried over sodium sulfate and concentrated under reduced pressure. The crude product was used in the next step without being purified further. Yield: 91% (1.1 g, 4.0 mmol).

1. concentrationThe solvent was concentrated under reduced pressure
2. additionthe residue was diluted with water (10 ml)
3. extractionThen extraction with ethyl acetate (2×50 ml)
4. washThe combined organic phases were washed with water (50 ml) and sat. NaCl solution (50 ml)
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated under reduced pressure
7. customwithout being purified further