title: Efficient synthesis of 1,3-diaryl-4-halo-1H-pyrazoles from 3-arylsydnones and 2-aryl-1,1-dihalo-1-alkenes.
abstract: An efficient synthesis of 1,3-diaryl-4-halo-1H-pyrazoles was achieved. The synthesis involves the [3 + 2] dipolar cycloaddition of 3-arylsydnones and 2-aryl-1,1-dihalo-1-alkenes. The process proceeds smoothly in moderate to excellent yields. 1,3-Diaryl-4-halo-1H-pyrazoles are found to be important intermediates that can easily be converted into 1,2,5-triaryl-substituted pyrazoles via Pd-catalyzed C-H bond activation.
authors.affiliation: Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092, China.
authors.forename: Yiwen
authors.initials: Y
authors.lastname: Yang
authors.forename: Chunxiang
authors.initials: C
authors.lastname: Kuang
authors.forename: Hui
authors.initials: H
authors.lastname: Jin
authors.forename: Qing
authors.initials: Q
authors.lastname: Yang
authors.forename: Zhongkui
authors.initials: Z
authors.lastname: Zhang