Abstract2,4‐Diaryl‐4‐(2,4‐dinitroaryl)‐5(4H)‐oxazolones2were prepared by arylation of the corresponding 5(4H)‐oxazolones1under phase‐transfer conditions with the corresponding 1‐halo‐2,4‐dinitrobenzenes. 2,4‐Diaryl‐4‐(3,5‐dinitro‐2‐pyridyl)‐5(4H)‐oxazolones5were obtained similarly from the corresponding1and 2‐chloro‐3,5‐dinitropyridine. On reaction with methanol andp‐toluenesulfonic acid, oxazolones2rearranged to the corresponding 1‐hydroxy‐1H‐indazole derivatives8. Under the same conditions oxazolones5afforded a mixture of the correspondingly substituted 1H‐pyrazolo[4,3‐b]pyridines7and substituted imidazo[1,5‐a]pyridines12. In all cases the solvolysis reaction, yielding substituted glycine esters9and11, was competi