Perchloric Acid → 1-amino-4-(methoxycarbonyl)pyridin-2(1H)-iminium 2,4,6-trimethylbenzenesulfonate

Participants

Reaction Conditions

Reaction Steps

70% Perchloric acid (18.9 ml) was added to a 1,4-dioxane (26 ml) solution of (Z)-ethyl N-(mesitylsulfonyl)oxyacetimidate (11.7 g) at 4° C. over 20 minutes. Thereafter, the reaction solution was stirred at 3° C. for 30 minutes, and it was then poured into water (100 ml). The precipitated solid was collected by filtration, and was then washed with water (45 ml) to obtain a white solid as a crude product. Methyl 2-aminoisonicotinate (5 g) was added to methylene chloride (35 ml), and the obtained mixture was then cooled to 3° C. The obtained crude product was dissolved in methylene chloride (40 ml), and only an organic layer was added to a methylene chloride solution of 2-aminoisonicotinate. The obtained mixture was stirred at 3° C. for 30 minutes. Thereafter, methyl tert-butyl ether (50 ml) was added to the reaction solution, and the precipitated solid was collected by filtration. The collected solid was washed with methyl tert-butyl ether (20 nil), and was then dried at 45° C., so as to obtain the title compound (10.7 g) in the form of a light yellow solid.

Provenance & Evidence