Ammonia → 3-Amino-4-methoxybenzo[b]thiophene-2-carboxamide

Participants

Reaction Steps

Lithium amide in liquid ammonia is prepared as described by Unangst P. C., Carethers M. E., J. Heterocyclic. Chem. 21, 709 (1984), from lithium metal ribbon (0.16 g, 23 mmol). A solution of methyl 3-amino-4-methoxybenzo[b]thiophene-2-carboxylate (1.3 g, 5.5 mmol) [Beck J. R., supra] in 10 mL of tetrahydrofuran is added dropwise. The mixture is stirred for 18 hours as the excess ammonia is permitted to evaporate. The residue is treated with 250 g of ice and water. The solid product is filtered, washed with water, and recrystallized from aqueous ethanol to yield 0.70 g (58%) of product; mp=151°-153° C.

Provenance & Evidence