Ce-catalyzed regioselective synthesis of pyrazoles from 1,2-diols via tandem oxidation and C-C/C-N bond formation

A novel and efficient cerium-catalyzed tandem oxidation and intermolecular ring cyclization of vicinal diols with hydrazones has been achieved for the regioselective synthesis of pyrazole derivatives. The corresponding 1,3-di- and 1,3,5-trisubstituted pyrazoles were obtained in moderate to excellent yields. The reaction has the advantages of mild conditions, easily available starting materials, broad substrate scope and good functional group tolerance.

Automated summary

A novel and efficient tandem oxidation and intermolecular ring cyclization reaction catalyzed by cerium has been developed for the regioselective synthesis of pyrazole derivatives. The corresponding 1,3-di- and 1,3,5-trisubstituted pyrazoles were obtained in moderate to excellent yields. The reaction offers the advantages of mild conditions, readily available starting materials, broad substrate scope, and good functional group tolerance.