Expeditious synthesis of C2- or N4-aryl-1,4-benzothiazin-3-one via orthogonal Pd-catalyzed C-arylation and Cu-catalyzed N-arylation
作者:Wei-Sheng Huang、Rongsong Xu、Rory Dodd、William C. Shakespeare
DOI:10.1016/j.tetlet.2013.11.053
日期:2014.1
Direct, chemo-specific arylation at C-2 or N-4 of 1,4-benzothiazin-3-one with aryl halides, based on Pd or Cu catalyst system, respectively, provided easy entry to arylated derivatives, a class of molecules not easily accessible via existing methods. Under Pd-catalysis conditions with LiHMDS as the base, N-arylation of 1,4-benzothiazin-3-one was inhibited leading to C alpha-arylation of a secondary amide without the need for protection and de-protection of more acidic amido NH. (C) 2013 Elsevier Ltd. All rights reserved.