Water → 5-Bromo-8-(4-methylpiperazin-1-yl)tetrazolo[1,5-a]pyrazine

Participants

Reaction Conditions

Reaction Steps

8-(4-Methylpiperazin-1-yl)tetrazolo[1,5-a]pyrazine (100 g, 0.456 mol, 1.0 eq.) was suspended in acetic acid (110 ml) under nitrogen and stirred at 35° C. until a solution was obtained. The solution was cooled to 16° C. and N-Bromosuccinimide (82.14 g, 0.461 mol, 1.01 eq.) is added at such a rate that the temperature of the reaction was maintained at 14-18° C. The reaction was monitored and additional aliquots of N-bromosuccinimide added as necessary to ensure conversion was ≧99.5% after 2-3 hours stirring at 20° C. stirring. Water was added, and the solution is cooled to 13° C. The pH of the suspension is adjusted to 8.3-8.5 by addition of triethylamine. The resulting suspension was filtered, washed with water, and dried to afford the desired product (136.02 g, 100% yield).

Provenance & Evidence