Sodium Hydroxide → 2,3,4,9-Tetrahydro-1H-carbazol-2-amine

Participants

Reaction Steps

A suspension of the crude 1,3,4,9-tetrahydrocarbazole-2-one oxime (1.093 g, 5.45 mmol) in ethanol (27.5 mL) was treated while cooling in ice bath with 2.5 N aqueous sodium hydroxide (22 mL). To the stirred dark solution kept under nitrogen was added portionwise over 15 minutes Al—Ni alloy (2.05 g). After 5 minutes the cooling bath was removed and the mixture stirred at room temperature for one hour. The catalysts was filtered off over Celite, the cake quickly washed under nitrogen with a small amount of 1:1 (v/v) ethanol-water and the filtrate was extracted three times with dichloromethane. The combined extracts were washed with water and brine and dried over anhydrous magnesium sulfate. Removal of the solvent provided a dark brown foam that crystallized upon standing. The residue was purified by flash chromatography over silica gel Merck 60 using a gradient from 3% to 10% of ammonia saturated methanol in dichloromethane to provide the title amine as a foam (0.791 g). MS (ES): [M+H]+ @m/z 187.1

Provenance & Evidence