N-Acetyl-L-Cysteine → Palladium

Participants

Reaction Steps

Crude 5′-(5-cyano-1-methyl-1H-pyrrol-2-yl)spiro[cyclohexane-1,3′-[3H]indol]-2′-ylidenecyanamide (1.0 g) containing residual Pd (5100 ppm) was suspended in THF (5 mL). Upon addition of aqueous 1M KOH (5 mL), a clear orange solution was obtained. N-Acetylcysteine (1.3 g) was added, the mixture was stirred for 1 hour, and filtered. Ten percent aqueous HCl (3 mL) was added dropwise to the filtrate causing precipitation of a white solid. The solution was filtered, the solid washed with methanol, and the washed solid dried to give 5′-(5-cyano-1-methyl-1H-pyrrol-2-yl)spiro[cyclohexane-1,3′-[3H]indol])-2′-ylidenecyanamide (0.6 g; 60% yield; 96 ppm Pd).

Provenance & Evidence