Facile Synthesis of Benzo[d]azol-2(3H)-ones Using 2-Phenoxycarbonyl-4,5-dichloropyridazin-3(2H)-one as Green CO Source.

Using title reagent (II), a number of benzo[d]oxazolones (III), -imidazolones (V) and -thiazolones (VII) and (IX) are easily prepared from 2-aminophenols (I), ortho-phenylenediamines (IV) and 2-aminothiophenols (VI) and (VIII) in high yields.