Potassium Hydroxide → Ethyl [4-(5-oxo-4,5-dihydropyrazin-2-yl)phenyl]carbamate

Participants

Reaction Steps

Ethyl N-hydroxy-N-phenylcarbamate (7.9 g) was added to a solution of potassium hydroxide (2.45 g) in ethanol (125 ml). After the solution had been stirred for 30 minutes, chloropyrazine (5 g) and a small amount of molecular sieve (4 A) pellets were added. The solution was stirred for two hours and allowed to stand for 144 hours to give a dark brown solution. This solution was evaporated under reduced pressure to give an oil which was washed with dilute acetic acid and solidified. This solid was recrystallised from n-propanol, stirred with water for two hours to remove salts, collected and dried to afford the title compound (1.8 g), m.p. 260°-262° C.

Provenance & Evidence