Insight into novel cyclization reactions using acetic anhydride in the presence of 4-dimethylaminopyridine
Reactions of acetic anhydride in the presence of 4-dimethylaminopyridine with 1,3-disubstituted ureas and hydrazobenzenes gave uracils and pyrazolines respectively.Unsymmetrical 1,3-disubstituted ureas react regioselectively.