‘One-pot’ synthesis of 4-substituted 1,5-diaryl-1H-pyrazole-3-carboxylates via lithium tert-butoxide-mediated sterically hindered Claisen condensation and Knorr reaction
作者:Jian-An Jiang、Wei-Bin Huang、Jiao-Jiao Zhai、Hong-Wei Liu、Qi Cai、Liu-Xin Xu、Wei Wang、Ya-Fei Ji
DOI:10.1016/j.tet.2012.11.012
日期:2013.1
A concise ‘one-pot’ synthesis of a variety of 4-substituted 1,5-diaryl-1H-pyrazole-3-carboxylates has been developed in moderate to good yields with excellent regioselectivity. Less cost lithium tert-butoxide has been identified as a base for sterically hindered Claisencondensation to efficiently generate the labile 3-substituted 4-aryl-2,4-diketoesters. Furthermore, extensive studies lead to a ‘one-pot’
Palladium-catalyzed late-stage mono-aroylation of the fully substituted pyrazoles via aromatic C–H bond activation
作者:Miao-Miao Chen、Ling-Yan Shao、Li-Jun Lun、Yu-Liang Wu、Xiao-Pan Fu、Ya-Fei Ji
DOI:10.1016/j.cclet.2018.09.022
日期:2019.3
5-diaryl-1H-pyrazole-3-carboxylates has been developed via direct and exclusive mono-Csp2 H bond activation with broad substrate scope and good functional group tolerance. A dual-core dimeric palladacycle is confirmed by X-ray single crystal crystallography, and probably serves as an activespecies in the catalyticcycle.