Methanesulfonic Acid → 3,5-Diamino-2,6-di(methylamino)pyridine

Participants

Reaction Steps

A 250 ml Parr bottle was charged with 2,6-di(methylamino)-3,5-dinitropyridine (20.0 g, 0.088 mole), 30 ml methanesulfonic acid, 200 ml methanol and 1.0 g 5% Pd/charcoal catalyst. The mixture was subjected to hydrogenation at ambient temperature with an initial hydrogen pressure of 65 psig. When no further uptake of hydrogen was observed, the mixture was treated with anhydrous silica gel (25 g), filtered free of catalyst and drying agent under a nitrogen atmosphere, and methanol removed under vacuum. The trimethanesulfonate salt of 3,5-diamino-2,6-di(methylamino)pyridine was obtained under nitrogen by addition of cold i-butanol-benzene to the concentrate, followed by vacuum drying (40°-50°C) over P2O5.

Provenance & Evidence