反应详情

To a solution of 2-methyl-3-nitrophenol K1 (1.1 g; 7.18 mmol) in THF (13 mL) was added cyclohexane (27 mL; a solution was maintained). tert-Butyl trichloroacetimidate K2 (5.36 mL; 28.73 mmol) was added followed by a catalytic amount of boron trifluoride etherate (143.8 μL; 1.14 mmol) and the reaction was stirred at room temperature for 15 h. The reaction was incomplete (by analytical HPLC) and an additional amount of tert-butyl trichloroacetimidate (1.4 mL; 7.51 mmol) was added (reaction remains in solution). The reaction was complete after stirring at room temperature for 5 h. Solid sodium bicarbonate was added, and the mixture was filtered, rinsed with dichloromethane and evaporated to dryness to provide a white solid. The solid was triturated with dichloromethane, the white solid filtered and discarded (=trichloroacetimide). The filtrate was concentrated and loaded onto a flash column for purification (hexane:EtOAc 9:1) to provide the pure 2-methyl-3-tert-butoxynitrobenzene K3 (1.17 g; 78%). Homogeneity by HPLC (TFA) @ 220 nm: 96%

1. temperaturea solution was maintained)
2. custom(reaction remains in solution)
3. stirringafter stirring at room temperature for 5 h
4. filtrationthe mixture was filtered
5. washrinsed with dichloromethane
6. customevaporated to dryness
7. customto provide a white solid
8. customThe solid was triturated with dichloromethane
9. filtrationthe white solid filtered
10. concentrationThe filtrate was concentrated
11. customloaded onto a flash column for purification (hexane:EtOAc 9:1)