Transition-Metal-BasedLewis Acid Catalysis of Aza-TypeMichael Additions of Amines toα,β-Unsaturated Electrophiles in Water
作者:Li-Wen Xu、Lyi Li、Chun-Gu Xia
DOI:10.1002/hlca.200490139
日期:2004.6
Several transition-metal-based Lewis acid catalysts, especially FeCl3⋅7 H2O, CrCl3⋅6 H2O, and SnCl4⋅4 H2O, were shown to be highly effective for aza-type Michael reactions between electrophilic α,β-unsaturated compounds and both aliphatic and aromatic amines in aqueous solution. Advantages of the new protocol include 1) high-yielding reactions that can be conducted at ambient temperature; 2) the use
Titania Nanoparticles Stabilized HPA in SBA-15 for the Intermolecular Hydroamination of Activated Olefins
作者:Dhanashri Sawant-Dhuri、Veerappan V. Balasubramanian、Katsuhiko Ariga、Dae-Hwan Park、Jin-Ho Choy、Wang Soo Cha、Salem S. Al-deyab、Shivappa B. Halligudi、Ajayan Vinu
DOI:10.1002/cctc.201402449
日期:2014.12
A liquid phase hydroamination (HA) of α,β‐ethylenic compounds with amines was investigated with TiO2 nanoparticlesstabilized 12‐tungstophosphoric acid (TPA) in SBA‐15. The catalysts were prepared by wet impregnation of TPA/TiO2 nanoparticles into the SBA‐15 and calcined at different temperatures. The characterization results reveal that the textural properties and the acidity of the prepared catalysts