Dimethylformamide → 5-Methoxy-2-methyl-1H-indole-3-carbonitrile

Participants

Reaction Steps

To a 0° C. solution of 5-Methoxy-2-methyl-1H-indole (5 g, 31.0 mmol), dry acetonitrile, (90 mL) was slowly added chlorosulfonyl isocyanate (3 mL, 34.1 mmol). The reaction was stirred and allowed to warm to room temperature and stirred for an additional four hours followed by the addition of dimethyl formamide (4.8 mL (62.0 mmol)and then stirred for an additional 1.5 hours at room temperature. The reaction was poured into water and extracted with diethyl ether. The aqueous layer was adjusted to pH 9 with 1M potassium carbonate, and extracted with diethyl ether. The ether layers were combined and dried over magnesium sulfate, filtered and concentrated. Crystallization of the residue from ether and hexane gave 5-methoxy-2-methyl-1H-indole-3-carbonitrile (3.86 g) in 67% yield as a light pink solid. C11H10N2O: GC/MS r.t.=4.06 min., m/z 186; 1H NMR (CDCl3): δ 7.22 (d, 1H, J=8.3 Hz), 7.08 (s, 1H), 6.86 (d, 1H, J=8.3 Hz), 3.86 (s, 3H), 2.60 (s, 3H) ppm.

Provenance & Evidence