Acetyl chloride → HCID 10867425, compound

Participants

Reaction Conditions

Reaction Steps

2,3-Dihydroxy-1H-indole-2-carboxamide (0.030 mol) was suspended in trichloromethane (400 ml). The mixture was cooled to 0° C. Triethylamine (0.045 mol) was added. Acetyl chloride (0.045 mol) was added over 2 minutes. After 30 minutes, TLC showed the reaction was incomplete. While the flask was still cool, more Triethylamine (6.26 ml) was added, followed 15 minutes later with more acetyl chloride (3.21 ml). TLC showed the reaction was still incomplete. The reaction was continued to allow to stir, cooled to 0° C., and more triethylamine (6.26 ml) was added. Over 2 minutes, more acetyl chloride (3.21 ml) was added neat. TLC showed 80% completion after 60 minutes, and no progress after 30 more minutes. A third portion of acetyl chloride and triethylamine was added. After an additional 15 minutes, ice cold water (200 ml) was added. The mixture was stirred for 10 minutes, filtered, and rinsed with water (3×100 ml) and trichloromethane (2×75 ml). The sample was allowed to dry overnight, yielding 4.71 g of (S)-1-acetyl-2,3-dihydro-1H-indole-2-carboxamide (intermediate 1, mp. >260° C.).

Provenance & Evidence