反应详情

To a solution of (1R)-3-methyl-1-trichloromethyl-2-butenyl acetoacetate (1.63 g., 5.68 mmole) from Example IA.2.(a) and triethylamine (0.57 g, 5.68 mmole) in 10 ml of acetonitrile was added dropwise in small portions at 7-10 minute intervals over a total period of 30 minutes a solution of tosyl azide (1.12 g, 5.68 mmole) in 2 ml of acetonitrile. After stirring at room temperature for 21/4 hours, the mixture was poured into 17 ml of aqueous 1N NaOH. After stirring an additional 45 minutes, the mixture was extracted three times with ether, and the combined ethereal extracts were dried over MgSO4. The dried solution was concentrated to give an orange oil. The oil was chromatographed on 8 (20×20 cm) preparative tlc plates (silica gel) with CH2Cl2 as eluent to afford (1R)-3-methyl-1-trichloromethyl-2-butenyl diazoacetate (0.96 g, 62% isolated yield) as a yellow oil; [α]D31 =+59° (hexane).

1. customwas added dropwise in small portions at 7-10 minute
2. customof 30 minutes
3. stirringAfter stirring an additional 45 minutes
4. extractionthe mixture was extracted three times with ether
5. dry with materialthe combined ethereal extracts were dried over MgSO4
6. concentrationThe dried solution was concentrated
7. customto give an orange oil
8. customThe oil was chromatographed on 8 (20×20 cm) preparative tlc plates (silica gel) with CH2Cl2 as eluent