1616468-53-1Relevant articles and documents
One-Pot Synthesis of Highly Substituted 1H-Pyrazole-5-carboxylates from 4-Aryl-2,4-diketoesters and Arylhydrazines
Zhai, Jiao-Jiao,Gu, Chun-Hui,Guo, Ying,Liao, Dao-Hua,Zhu, Dun-Ru,Ji, Ya-Fei
, p. 840 - 848 (2016)
A one-pot synthesis of highly substituted 1H-pyrazole-5-carboxylates 1 has been developed starting from easily available 4-aryl-2,4-diketoesters 2 and arylhydrazine hydrochlorides 3. More active 2-carbonyl group of 2 was blocked with methoxyamine hydrochloride to give 2-methoxy imine intermediates, which were then subjected to condensation cyclization with 3 in situ to provide the desired products 1. In addition, the geometrical configuration of 1aa was unambiguously confirmed by single crystal X-ray crystallography.
One-pot tandem synthesis of tetrasubstituted pyrazoles via 1,3-dipolar cycloaddition between aryl hydrazones and ethyl but-2-ynoate
Ningaiah, Srikantamurthy,Doddaramappa, Shridevi D.,Chandra,Madegowda, Mahendra,Keshavamurthy, Shubakara,Bhadraiah, Umesha K.
, p. 2222 - 2231 (2014/07/07)
1,3,4,5-Tetrasubstituted pyrazoles are rapidly and regioselectively synthesized in a one-pot, three-step sequence consisting of condensation, nitrilimine generation, and cycloaddition using mercuric acetate. Newly synthesized compounds were characterized by spectral studies. Regiochemistry of compounds 6a and 8a was determined as 1,4- and 1,5-regioisomers respectively by X-ray crystallography. Copyright