One-pot synthesis of 1-alkyl-1H-indazoles from 1,1-dialkylhydrazones via aryne annulation
作者:Nataliya A. Markina、Anton V. Dubrovskiy、Richard C. Larock
DOI:10.1039/c2ob07117g
日期:——
The reaction of readily accessible 1,1-dialkylhydrazones with commercially available o-(trimethylsilyl)aryl triflates provides a direct one-step route to pharmaceutically important 1-alkylindazoles. The products are obtained in high yields by one-pot NCS-chlorination/aryne annulation or Ac2O-acylation/deprotection/aromatization protocols.
Palladium-Catalyzed C–H/C–H Cross-Coupling by Mechanochemistry: Direct Alkenylation and Heteroarylation of N1-Protected 1<i>H</i>-Indazoles
作者:Jingbo Yu、Xinjie Yang、Chongyang Wu、Weike Su
DOI:10.1021/acs.joc.9b02951
日期:2020.1.17
C3-(hetero)arylated 1H-indazoles are privileged structural motifs in numerous pharmaceuticals. Direct C3-alkenylation and C3-(hetero)arylation of 1H-indazoles have been significantly challenging because of the inert nature of this carbon center. Herein, we present an efficient mechanochemical strategy for palladium-catalyzed C-H/C-H cross-coupling to construct C3-alkenylated and C3-heteroarylated 1H-indazoles using