反应详情

N-(tert-butyloxycarbonyl)-S-methylisothiourea (2 g) was dissolved in dichloromethane (20 ml). To the solution, a 4N sodium hydroxide solution (2 ml) was added with stirring. The reaction mixture was placed in an ice bath; N-(benzyloxy-carbonyloxy)-succinimid (2.62 g) in dichloromethane (20 ml) was added dropwise together with a 2N sodium hydroxide solution to keep the pH around 11. After addition was complete, the reaction mixture was stirred overnight at room temperature. The dichloromethane layer was separated, and the aqueous layer was washed twice with dichloromethane. The combined organic layers were washed with water and dried over sodium sulfate, filtered and evaporated in vacuo. The residue was purified by chromatography on silica (eluent: heptane/ethyl acetate=3/2 v/v %) to yield N-(benzyloxy-carbonyl)-N'-(tert-butyloxycarbonyl)-S-methylisothiourea (3.15 g).

1. customThe reaction mixture was placed in an ice bath
2. additionAfter addition
3. stirringthe reaction mixture was stirred overnight at room temperature
4. customThe dichloromethane layer was separated
5. washthe aqueous layer was washed twice with dichloromethane
6. washThe combined organic layers were washed with water
7. dry with materialdried over sodium sulfate
8. filtrationfiltered
9. customevaporated in vacuo
10. customThe residue was purified by chromatography on silica (eluent: heptane/ethyl acetate=3/2 v/v %)