Lewis acid catalyzed Markovnikov hydrobromination and hydrochlorination of alkynes using TMSX (X = Br, Cl)

Abstract

The Markovnikov hydrobromination and hydrochlorination of alkynes were achieved using TMSX (X = Br, Cl) instead of corrosive HX (X = Br, Cl) as the bromination and chlorination reagents. Mn(OAc)2.4H2O...

Mn(II)-Catalyzed Markovnikov Hydroiodination of Terminal Aryl Alkynes

“…Recently, we achieved the hydrobromination and hydrochlorination of alkynes in the presence of Mn(II) and Zn(II) catalysts. 16 Herein, we would like to report our findings on the Mn(II)catalyzed hydroiodination reaction of terminal aryl alkynes. The current methodology featured the cheap Mn(II) catalyst, mild conditions, and gram-scale synthesis.…”

“…In our previous hydrohalogenation reactions using TMSX (X = Br, Cl), we found that the choice of Lewis acid catalyst was based on both the Lewis acidity of TMSX and the electronic factors of substrates. 16 For electron-neutral/rich alkynes, Mn(OAc) 2 •4H 2 O was the hydrobromination catalyst. For hydrobromination of electron-deficient alkynes and hydrochlorination of alkynes, Zn(OAc) 2 •2H 2 O was employed as the catalyst.…”

“…So, we assume that other TMSX reagents could be explored in the classical HX-involved reactions with the help of a catalyst. Recently, we achieved the hydrobromination and hydrochlorination of alkynes in the presence of Mn(II) and Zn(II) catalysts . Herein, we would like to report our findings on the Mn(II)-catalyzed hydroiodination reaction of terminal aryl alkynes.…”