反应详情

温度

23 °C

To a solution of 1,8-diazabicyclo[5.4.0]undec-7-ene (10.6 g, 10.5 ml, 69.6 mmol, Eq: 1.04) in THF (59.0 ml) at 5° C. was added dropwise a solution of allyl 2-(3-nitrophenyl)acetate (intermediate B3a) (14.8 g, 66.9 mmol, Eq: 1.00) and 4-acetamidobenzenesulfonyl azide (16.6 g, 68.9 mmol, Eq: 1.03) in THF (118 ml) within 40 min and the mixture was stirred at 23° C. for 18 h protected from light. Quenched with sat. NH4Cl-sol., diluted with ethyl acetate, separated phases, the organic layer was washed with brine and dried over Na2SO4. Removal of the solvent in vacuum left an orange semisolid, diluted with diethyl ether, filtered the solid off, washed with diethyl ether, the filtrate was concentrated in vacuum to give an orange semisolid. The crude material was purified by flash chromatography (silica gel, 300 g, 25% to 30% EtOAc in heptane) to give the title compound as a yellow solid (15.62 g, 94%).

1. customQuenched with sat. NH4Cl-sol
2. addition, diluted with ethyl acetate
3. customseparated phases
4. washthe organic layer was washed with brine
5. dry with materialdried over Na2SO4
6. customRemoval of the solvent in vacuum
7. waitleft an orange semisolid
8. additiondiluted with diethyl ether
9. filtrationfiltered the solid off,
10. washwashed with diethyl ether
11. concentrationthe filtrate was concentrated in vacuum
12. customto give an orange semisolid
13. customThe crude material was purified by flash chromatography (silica gel, 300 g, 25% to 30% EtOAc in heptane)