title: PTSA-catalyzed Mannich-type-cyclization-oxidation tandem reactions: one-pot synthesis of 1,3,5-substituted pyrazoles from aldehydes, hydrazines and alkynes.
abstract: A convenient one-pot Mannich-type-cyclization-oxidation tandem process has been developed for the synthesis of 1,3,5-trisubstituted pyrazoles derivatives from aldehydes, hydrazines and alkynes using p-toluenesulfonic acid monohydrate (PTSA) as a multifunctional catalyst. This method provides a flexible and rapid route to 1,3,5-trisubstituted pyrazoles.
authors.affiliation: Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Chemical Engineering of Guangxi Normal University, Guilin 541004, People's Republic of China.
authors.forename: Pei
authors.initials: P
authors.lastname: Liu
authors.forename: Ying-Ming
authors.initials: YM
authors.lastname: Pan
authors.forename: Yan-Li
authors.initials: YL
authors.lastname: Xu
authors.forename: Heng-Shan
authors.initials: HS
authors.lastname: Wang
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D000480:Alkynes / Q000737:chemistry*; D001557:Benzenesulfonates / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D006834:Hydrazines / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011720:Pyrazoles / Q000138:chemical synthesis*
chemical_list: D000447:Aldehydes; D000480:Alkynes; D001557:Benzenesulfonates; D006834:Hydrazines; D011720:Pyrazoles; C029501:4-toluenesulfonic acid