反应详情

A stirred solution of the crude 5-chloro-1H-spiro[indole-3,3′-pyrrolidine]-2,2′,5′-trione, intermediate 9 (800 mg, 3.19 mmol) in anhydrous N,N-dimethylformamide (6 ml) was treated with potassium tert-butoxide (377 mg, 3.19 mmol). After stirring at ambient temperature for 40 min, benzyl bromide (0.38 ml, 3.19 mmol) was added. The mixture was stirred for 2 hours and left to stand overnight. The resultant mixture was diluted with water (50 ml) and extracted with ethyl acetate (3×50 ml). The combined extracts were dried (MgSO4) and the solvent removed in vacuo to give the crude 1′-benzyl-5-chloro-1H-spiro[indole-3,3′-pyrrolidine]-2,2′,5′-trione which was purified by flash chromatography (silica) eluting with petroleum ether (40-60) containing an increasing amount (0 to 75%) of ethyl acetate. This gave 789 mg (73%) of a yellow solid.

1. stirringThe mixture was stirred for 2 hours
2. waitleft
3. waitto stand overnight
4. extractionextracted with ethyl acetate (3×50 ml)
5. dry with materialThe combined extracts were dried (MgSO4)
6. customthe solvent removed in vacuo