Copper-Mediated C4-Benzylations of 5-Aminopyrazoles with 3-Indoleacetic Acids

作者：Gao, Qiwen; Tian, Jinhong; Wen, Kangmei; Chen, Chen; Yao, Xingang; Pang, Jianxin^*; Tang, Xiaodong^*

来源：Journal of Organic Chemistry, 2023, 88(11): 6623-6632.

DOI：10.1021/acs.joc.2c02972

• ALPHA-ALKYLATION
• CATALYZED ALKYLATION
• ALCOHOLS
• KETONES
• STRATEGY

Herein, we present a copper-mediatedC4-benzylation of5-aminopyrazoleswith 3-indoleacetic acids. Various benzylated 5-aminopyrazoles areprepared in good-to-excellent yields under basic and ligand-free conditionsin the presence of copper acetate. Moreover, this benzylation methodis applicable to other substrates, including naphthylamine, 2-aminochromen-4-one,and enamines. Some products exhibit antiproliferative activities againstcancer cell lines. In addition, the C4-benzylated products are cyclizedinto 1H-pyrazolo-[4 ',3 ':6,7]-azepino-[3,4-b]-indoles with aldehydes via one-pot two-step processes;notably, the cyclized products exhibit fluorescence emissions withlarge Stokes shifts.

• 单位
  南方医科大学