UN PROCEDIMIENTO PARA LA PREPARACION DE ALGUNAS 3(2H)-1,2-DIAZIN-2-ONAS SUSTITUIDAS

摘要

3(2h)1,2-diazin-3(2H)-ones of formula (I); are made by (a) reacting a 1,2-diazin-3(2H)-one of formula (II) with an alcohol of formula (III) to give derivs. of formula (I) in which R4 and R5 together form a 5-membered ring with two substits. R6R7C; (b) reacting these with a diluted mineral or organic acd at 20-110 deg. C for 10 mins. to 10 hours to obtn. derivs. of formula (I) in which R4 and R5 are H; and (c) opt. subjecting these to catalytic hydro-halogenation in presence of hydrogen; to give cpds. of formula (I) in which R2 or R3 is H.