Prepn. of 3-aryl-quinazolin-2,4-di:one derivs., useful as intermediates for pharmaceuticals and plant-protecting agents

摘要

Prepn. of substd. 3-arylquinazolin-2,4-diones of formula (I) comprises: (A) reacting a nitro cpd. of formula (II) with an anthranilic acid deriv. of formula (III) and carbon monoxide in the presence of a catalyst, a ligand and a solvent to give (I); or (B) (a) reacting (II) with an alcohol of formula R10OH (IV) and carbon monoxide in the presence of a catalyst, a ligand and a solvent to give a carbamate of formula (V); and (b) treating (V) with (III) in the presence of a base and in an aprotic solvent to give (I): R1-R4 = H, halo, 1-12C alkyl, 1-12C alkoxy, Ar or ArO; Ar = a gp. of formula (a); R5-R9 = H, halo, 1-12C alkyl, 1-12C alkoxy, phenyl, phenoxy or any pair of adjacent R groups may form an additional aromatic ring; and R10 = 1-12C alkyl.