2-Amino-4-bromopyridine → 1,2-Diamino-4-bromo-pyridinium 2,4,6-trimethyl-benzenesulfonate

Participants

Reaction Steps

To a cooled suspension of O-(mesitylsulfonyl)hydroxylamine (11.22 g, 52.1 mmol, 1 eq) in dichloromethane (130 ml) is portionwise added 4-bromopyridin-2-amine (9.3 g, 52.1 mmol, 1 eq.) (exothermic reaction, some cooling is needed) giving a white suspension. After 1 hour the white suspension is diluted with diethyl ether (120 ml). The white solid is collected by filtration, washed with diethyl ether and dried affording 1,2-diamino-4-bromo-pyridinium 2,4,6-trimethyl-benzenesulfonate (16.74 g, 82.7%) as white crystals. mp.: 176-180° C. MS: m/z=188.2, 190.2 (M+H+).

Provenance & Evidence