反应详情

tert-Butyl 1,1-dioxothiomorpholine-4-carboxylate (2.03 g, 8.63 mmol) was dissolved in a mixture of hydrochloric acid-methanol 10 (20 ml) and tetrahydrofuran (20 ml); hydrochloric acid (4.0 ml) was added thereto during stirring at room temperature; and the reaction mixture was stirred at room temperature for 3 hours. The reaction mixture was concentrated; methanol (20 ml), tetrahydrofuran (20 ml) and hydrochloric acid (4.0 ml) were added to the obtained crystals. Furthermore, water (10 ml) was added to this solution to perfectly dissolve the crystals; and this solution was stirred at room temperature for 1 hour. The solvent was concentrated under reduced pressure; and the obtained crystals were suspended in methanol, filtered off, washed with methanol, and dried under aeration to yield the title compound as colorless crystals (1.49 g, 8.65 mmol, quantitative).

1. stirringand the reaction mixture was stirred at room temperature for 3 hours
2. concentrationThe reaction mixture was concentrated
3. additionmethanol (20 ml), tetrahydrofuran (20 ml) and hydrochloric acid (4.0 ml) were added to the obtained crystals
4. additionFurthermore, water (10 ml) was added to this solution
5. dissolutionto perfectly dissolve the crystals
6. stirringand this solution was stirred at room temperature for 1 hour
7. concentrationThe solvent was concentrated under reduced pressure
8. filtrationfiltered off
9. washwashed with methanol
10. customdried under aeration