Sodium Dithionite → HCID 18315463, compound

Participants

Reaction Steps

A mixture of 3-[(2-chlorophenyl)methyl]amino-4-nitrobenzoic acid (6 g, 19.6 mmol), tetrahydrofuran (60 mL) and 5% sodium bicarbonate solution (50 mL) was treated portionwise with sodium hydrosulfite (4 g). The resulting clear solution had a pH of 6.29 that was adjusted to pH 7.15 by the addition of solid sodium bicarbonate. Additional sodium hydrosulfite was added (12 g) over several hours, and the mixture was stirred overnight. The tetrahydrofuran phase was separated, concentrated and triturated with ether/methylene chloride/hexane to afford 5.07 g of solid. Crystallization from methanol followed by washing with cold dilute aqueous methanol provided 4.79 g (88%) of pink-to-white crystals of 4-amino-3-[(2-chlorophenyl)methyl]aminobenzoic acid; mp 176°-177° C.

Provenance & Evidence