Reaction of hydrazobenzene with schiff bases, aldehydes and acetonylacetone in acetic acid

The reaction of hydrazobenzene with benzylideneaniline in acetic acid gives dibenzylidenebenzidine. It has been shown that in this reaction, acetic acid functions as an acid catalyst causing benzidine rearrangement, while benzylideneaniline serves as a potential source of aldehyde. The driving force for the observed transarylidenation reaction appears to be the enhanced conjugation in the resulting product. The reaction between dibenzylidenebenzidine and cinnamalaniline (cinnamaldehyde) has yielded the dicinnamylidene benzidine, supporting the above conclusion.