Alkynylation of benzotriazole with silylethynyliodonium triflates. Regioselective synthesis of 2-ethynyl-2H-benzotriazole derivatives

Tsugio Kitamura; Mohammad Hasan Morshed; Satoru Tsukada; Yuki Miyazaki; Naomi Iguchi; Daisuke Inoue

doi:10.1021/jo2015467

Alkynylation of benzotriazole with silylethynyliodonium triflates. Regioselective synthesis of 2-ethynyl-2H-benzotriazole derivatives

J Org Chem. 2011 Oct 7;76(19):8117-20. doi: 10.1021/jo2015467. Epub 2011 Aug 29.

Authors

Tsugio Kitamura¹, Mohammad Hasan Morshed, Satoru Tsukada, Yuki Miyazaki, Naomi Iguchi, Daisuke Inoue

Affiliation

¹ Department of Chemistry and Applied Chemistry, Graduate School of Science and Engineering, Saga University, Honjo-machi, Saga 840-8502, Japan. kitamura@cc.saga-u.ac.jp

PMID: 21854042
DOI: 10.1021/jo2015467

Abstract

Phenyl(trimethylsilylethynyl)iodonium and tert-butyldimethylsilylethynyl(phenyl)iodonium triflates were applied to alkynylation of benzotriazole. Treatment of the silylethynyliodonium triflates with the potassium salt of benzotriazole ion in (t)BuOH and CH(2)Cl(2) gave 2-(trimethylsilylethynyl)-2H-1,2,3-benzotriazole and 2-(tert-butyldimethylsilylethynyl)-2H-1,2,3-benzotriazole in 74% and 76% yields, respectively. The regioisomers, 1-silylethynyl-1H-1,2,3-benzotriazole derivatives, were minor. In both cases of the silyl-substitued ethynyliodonium salts, novel regioselective alkynylation of benzotriazole at the 2 position was observed.