A one-pot, three-component coupling of aldehydes with hydrazines and 1-aryl-1-alkenyl sulfones or 2-aryl-1-alkenyl sulfones for the regioselective synthesis of 1,3,4-and 1,3,5-triarylpyrazoles was developed. In our developed procedure, 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) worked as

Regioselective, One-Pot, Three-Component Synthesis of 1,3,4-and 1,3,5-Triarylpyrazoles from 1-and 2-Aryl-1-alkenyl Sulfones. -Aldehydes and hydrazines are used together with the title sulfones which control the regioselectivity of the product formation. DDQ is found to be an effective oxidant and the addition of the strong acid TFA is not required. Thus, products like (VIII), (X), (XII), and (XIV) bearing aryl moieties with acid-labile functionality can be synthesized in one pot. -(FUSE*, S.; SUGIYAMA, H.; KOBAYASHI, D.; IIJIMA, Y.; MATSUMURA, K.; TANAKA, H.; TAKAHASHI, T.; Eur. J. Org. Chem. 2015, 21, 4756-4764, http://dx.