Aluminium Powder-Catalyzed Regio- and Stereoselective Aminobromination of α,β-Unsaturated Carbonyl Compounds and Simple Olefins with the<i>p</i>-Toluenesulfonamide/<i>N</i>-Bromosuccinimide (TsNH<sub>2</sub>-NBS) System
作者:Zhan-Guo Chen、Jun-Fa Wei、Ming-Zhen Wang、Li-Yan Zhou、Cong-Jie Zhang、Xian-Ying Shi
DOI:10.1002/adsc.200900343
日期:2009.10
The regio- and stereoselective aminobromination of α,β-unsaturated carbonyl compounds and simple olefins catalyzed by elementary aluminium powder has been established by using p-toluenesulfonamide (TsNH2) and N-bromosuccinimide (NBS) as the nitrogen/bromine sources. The reaction was convenient to carry out with a loading of 1 mol% catalyst at room temperature without inert gas protection. This method
Copper Powder-Catalyzed Regio- and Stereoselective Aminobromination of α,β-Unsaturated Ketones with TsNH<sub>2</sub> and NBS as Nitrogen and Halogen Sources
The regio- and stereoselective aminobromination of α,β-unsaturated ketones catalyzed by copper powder has been established with 4-TsNH2 and NBS as the nitrogen/bromine sources, respectively. This method provides an easy access for preparation of vicinal aminohalo derivatives in the presence of 1 mol % catalyst. Electron-rich α,β-unsaturated ketones afforded the corresponding aminobrominated products
KI-catalyzed aminobromination of olefins with TsNH2–NBS combination
作者:Jun-fa Wei、Li-hui Zhang、Zhan-guo Chen、Xian-ying Shi、Jing-jing Cao
DOI:10.1039/b904789a
日期:——
efficient KI-catalyzed aminobromination of olefins has been developed with good to excellent yields and high regio- and stereoselectivities under transition metal-free conditions. A series of olefins, including α,β-unsaturated carbonyl compounds and simple olefins, was studied. The reaction was performed in CH2Cl2 using KI as the catalyst and TsNH2 and NBS as the nitrogen and brominesources.
Silicon Powder: The First Nonmetal Elemental Catalyst for Aminobromination of Olefins with TsNH<sub>2</sub> and NBS
作者:Jun-Fa Wei、Zhan-Guo Chen、Wei Lei、Li-Hui Zhang、Ming-Zheng Wang、Xian-Ying Shi、Run-Tao Li
DOI:10.1021/ol9015833
日期:2009.9.17
alternative to transition metal catalysts for aminobromination of α,β-unsaturated carbonyl compounds and simple olefins with p-toluenesulfonamide (4-TsNH2) and NBS, affording the aminobrominated products in high yields and regio- and stereoselectivity. The high reactivity of electron-rich substrates reveals that the reaction has the electrophilic addition feature.
(+)-Tartaric Acid-Catalyzed High Regio- and Stereoselective Aminobromination of Olefins
作者:Zhanguo Chen、Junfa Wei、Wenli Li、Yun Wang、Pengfei Zhao、Xianying Shi
DOI:10.1002/cjoc.201180302
日期:2011.8
X‐ray structural analysis of products 2b and 12c. The electron‐rich and deficient olefins show significant differences in activity to the aminobromination reaction and give the opposite regioselectivities. The 21 cases have been investigated which indicated that our protocol has the advantage of a large scope of olefins. Additionally, tartaric acid as catalyst has the advantage of avoiding any hazardous