Iron Oxide Nanoparticles Grown on Carboxy-Functionalized Graphite: An Efficient Reusable Catalyst for Alkylation of Arenes
作者:Vikul Rajpara、Subhash Banerjee、Grigoriy Sereda
DOI:10.1055/s-0029-1218851
日期:2010.8
hybrid catalyst by growing iron oxide nanoparticles on carboxy-functionalized graphite. This hybrid catalyst demonstrated superior catalytic activity towards the alkylation of arenes with alkyl halides in contrast to commercial graphite or unsupported iron oxide nanoparticles in terms of yields and general applicability. The catalyst can be reused up to five times with a minimal loss of catalytic activity
Tin exchanged heteropoly tungstate: An efficient catalyst for benzylation of arenes with benzyl alcohol
作者:Ch. Ramesh Kumar、K.T. Venkateswara Rao、P.S. Sai Prasad、N. Lingaiah
DOI:10.1016/j.molcata.2011.01.008
日期:2011.3
The partial exchange of tin with the protons of 12-tungstophosphoric acid (TPA) results in a highly active heterogeneous catalyst for benzylation of arenes with benzyl alcohol as benzylating agent. The catalysts were characterized by X-ray diffraction, Laser-Raman and FT-IR of pyridine adsorption. The catalytic activity depends significantly on the extent of tin exchanged with the protons of heteropoly tungstate. The characterization results suggest the presence of Lewis acidic sites by the exchange of tin. The catalyst with partial exchange of Sn showed high benzylation activity, which in turn related to variation in acidity of the catalysts. The catalyst is highly active for benzylation reaction irrespective of the nature of substituted arenes and benzyl alcohols. These catalysts are highly active compared to other acid catalysts used for benzylation of different arenes. The catalyst is easy to separate from reaction mixture and exhibit consistent activity upon reuse. The plausible reaction mechanism based on the role of both Lewis and Bronsted acid sites of the catalyst was discussed. (C) 2011 Elsevier B.V. All rights reserved.
Gold-Catalyzed Friedel-Crafts-Like Reaction of Benzylic Alcohols to Afford 1,1-Diarylalkanes
作者:James V. Oakley、Tyler J. Stanley、Kate A. Jesse、Amanda K. Melanese、Araceli A. Alvarez、Aloha L. Prince、Stephanie E. Cain、Anna G. Wenzel、Robert G. Iafe
DOI:10.1002/ejoc.201901082
日期:2019.11.14
A gold‐catalyzed, Friedel–Crafts‐like benzylation of unactivated benzylic alcohols to form 1,1‐diarylalkanes has been developed. The operationally convenient method uses only 1.3 equivalents of electron‐rich arene, employs readily available starting materials, is highly reproducible, and is tolerant to moisture. Moderate‐to‐high product yields (34–99 %) with excellent regioselectivity were obtained