Titanium superoxide: a heterogeneous catalyst for anti-Markovnikov aminobromination of olefins
作者:Tanveer Mahamadali Shaikh、Pratibha U. Karabal、Gurunath Suryavanshi、Arumugam Sudalai
DOI:10.1016/j.tetlet.2009.03.169
日期:2009.6
A new facile procedure for the aminobromination of olefins in high yields has been described using p-toluene sulfonamide (p-TsNH2) and N-bromosuccinimide (NBS) as nitrogen and bromine sources, respectively, and titanium superoxide as a truly heterogeneous catalyst. The formation of anti-Markovnikov product exclusively in all the cases studied possibly proceeding through a free radical reaction pathway
The carbon dioxide (CO2)-induced amidobromination of olefins with bromamine-T is described. The method can be used in reactions with a wide range of olefins, both aromatic and aliphatic, as well as electron-rich and deficient olefins, leading to the regioselective formation of amidobrominated compounds.
Atmosphere- and Temperature-Controlled Regioselective Aminobromination of Olefins
作者:Wesley Zongrong Yu、Yi An Cheng、Ming Wah Wong、Ying-Yeung Yeung
DOI:10.1002/adsc.201600821
日期:2017.1.19
A complete switch of regioselectivity in the aminobromination of olefins is realized from delicate changes in the reaction temperature from 25 °C to 40 °C and the atmosphere from air to argon, under catalyst‐free conditions. The resulting α‐bromoamides can be transformed easily to high‐value compounds (e.g., Clobenzorex). Mechanistic studies revealed that the reaction went through a radical pathway