Synthesis of 2‐( o ‐chloropheny)‐ and 2‐(2′,6′‐dichlorophenyl)‐4‐formyl‐1,2,3‐triazoles

Mesoaldehyde 1,3‐dioxime was treated with either o ‐chlorophenyl‐ or 2,6 dichloro‐phenylhydrazine to give the corresponding 2‐chlorophenylhydrazone. Hydrazones 1a and 1b were treated with acetic anhydride and cyclized to triazoles ( 3a and 6a ) with cesium carbonate. These were then hydrolized to the previously unknown chlorophenyltriazole aldehydes ( 4a and 4b ). They were also converted to a number of acid derivatives, alcohols, and amines.