反应详情

To a solution of 8.4 g of 4-chlorobenzenesulfonyl chloride (0.04 mole) and 6.9 g of N-trimethylsilyl-2-pyrrolidone (0.044 mole) in 50 ml of anhydrous tetrahydrofuran was added 0.2 ml of trimethylamine, and the mixture was stirred at the reflux temperature for 30.5 hours. The solvent was removed from the reaction under reduced pressure, and the residue was dissolved in 50 ml of chloroform. After addition of 15 g of silica gel (Wako Gel C-200) to the solution, chloroform was again removed under reduced pressure. The powdery residue thus obtained was supended in a mixed solvent of hexane-ethyl acetate (7:3). The suspension was subjected to chromatography on a column (D 40 mm×L 500 mm) of 300 g of silica gel (Wako Gel C-200). Elution with a mixed solvent of hexane-ethyl acetate (7:3) followed by a mixed solvent of hexane-ethyl acetate (3:2) gave a crystalline product, which was recrystallized from a mixed solvent of chloroform-ether to give 5.83 g of N-(4'-chlorobenzenesulfonyl)-2-pyrrolidone as crystals.

1. customThe solvent was removed from the reaction under reduced pressure
2. dissolutionthe residue was dissolved in 50 ml of chloroform
3. additionAfter addition of 15 g of silica gel (Wako Gel C-200) to the solution, chloroform
4. customwas again removed under reduced pressure
5. customThe powdery residue thus obtained
6. washElution with a mixed solvent of hexane-ethyl acetate (7:3)
7. customgave a crystalline product, which
8. customwas recrystallized from a mixed solvent of chloroform-ether