Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Ta-Hseuh Road, Hsinchu 300-10, Taiwan, ROC.
Department of Chemistry, MES Abasaheb Garware College, Pune 411004, India.
J Org Chem. 2022 Sep 16;87(18):12109-12114. doi: 10.1021/acs.joc.2c01208. Epub 2022 Aug 25.
A facile synthesis of novel indazole-fused pyrazoles from pyrazol-3-ones and alkynoate esters/amides via Rh(III)-catalyzed sequential C-H activation/-alkenylation/intramolecular cyclization cascade is reported. The important characteristic of this method is that the resulting scaffold bearing quaternary carbon has been obtained through unusual [4 + 1] rather than expected [4 + 2] addition where alkynoate acts as a one-carbon unit.
本文报道了一种通过 Rh(III)催化的顺序 C-H 活化/烯丙基化/分子内环化级联反应,从吡唑-3-酮和炔酸酯/酰胺合成新型吲唑并吡唑的简便方法。该方法的重要特点是,通过不寻常的[4+1]而不是预期的[4+2]加成得到了带有季碳原子的产物,其中炔酸酯作为一个一碳单元。