反应详情

温度

2.5 °C

To a solution of benzylamine (10.92 ml, 100 mmol) in dichloromethane (DCM) (150 ml) was added triethylamine (13.67 ml, 100 mmol) followed by a solution of 2-nitrobenzene-1-sulfonyl chloride (22.16 g, 100 mmol) in DCM (70 ml) at 5-10° C. with stirring. The mixture was stirred for 1 hour (complete by HPLC), stirring continued for 1 hour, washed with water, brine, most of DCM removed on a rotavap, Ethyl acetate (150 ml) was added, another 25-30 ml distilled off under reduced pressure. To the resulting solution potassium tert-butoxide (0.561 g, 5.00 mmol) was added followed by methyl vinyl ketone (9.07 ml, 110 mmol) with stirring in one portion at 20-25° C. The mixture was stirred for 1 hour at 20-25° C., diluted with heptane (70 ml), washed with brine+1N HCl (5 ml), organic phase was dried (MgSO4), evaporated to approx 100 ml, seeded with crystals of compound F (crystallisation started), cooled to 0-5° C., diluted slowly with heptane to approx 200 ml. The mixture was aged in ice for 1 hour, crystals collected, washed with heptane, dried on air to give N-benzyl-2-nitro-N-(3-oxobutyl)benzenesulfonamide (31.4 g, 87 mmol, 87% yield).

1. stirringThe mixture was stirred for 1 hour (complete by HPLC)
2. stirringstirring
3. washwashed with water, brine, most of DCM
4. customremoved on a rotavap
5. additionEthyl acetate (150 ml) was added
6. distillationanother 25-30 ml distilled off under reduced pressure
7. stirringwith stirring in one portion at 20-25° C
8. stirringThe mixture was stirred for 1 hour at 20-25° C.
9. washwashed with brine+1N HCl (5 ml), organic phase
10. dry with materialwas dried (MgSO4)
11. customevaporated to approx 100 ml
12. additiondiluted slowly with heptane to approx 200 ml
13. waitThe mixture was aged in ice for 1 hour
14. customcrystals collected
15. washwashed with heptane
16. customdried on air