1595-06-8Relevant articles and documents
Indium(III) triflate - A catalyst for greener aromatic alkylation reactions
Mack, Ryan,Askins, Grant,Lowry, Jacob,Hurley, Nathan,Reeves, Perry C.
, p. 1262 - 1265 (2014/01/06)
An environmentally friendly method for alkylating aromatic compounds with simple alcohols in the presence of a catalytic amount of indium(III) triflate is reported. Ionic liquids are used as solvents and energy-efficient heating is provided by microwave radiation. Good yields are obtained with benzyl, secondary, and tertiary alcohols. Simple primary alcohols are not effective alkylating agents under these conditions. With tertiary alcohols, activated aromatic compounds such as toluene and anisole must be used to obtain good yields. The catalyst, which is immobilized in a water-insoluble ionic liquid, can be easily recycled without significant loss of activity.
Microwave-assisted silica-supported aluminum chloride-catalyzed Friedel-Crafts alkylation
Zupp, Laurine R.,Campanella, Veronica L.,Rudzinski, Diandra M.,Beland, Franois,Priefer, Ronny
, p. 5343 - 5346 (2012/10/30)
Microwave irradiation is a popular method in organic synthesis to achieve high yields in shorter reaction times. This decreases total 'man-hours' in a synthetic setting. Another technique used in organic chemistry to decrease manual manipulations, is solid support reagents. The benefits of this approach is that upon completion of a reaction, a simple filtration can be performed which expedites the work-up and also produces less organic waste. Friedel-Crafts alkylation has been explored using microwave chemistry as well as with solid-supported reagents. In comparison with traditional heating, as well as with AlCl3, superior yields were observed with silica-gel bound aluminum chloride (Si-AlClx) when microwave irradiated for only 5 min.
Catalytic alkylation of aryl Grignard reagents by iron(iii) amine-bis(phenolate) complexes
Qian, Xin,Dawe, Louise N.,Kozak, Christopher M.
experimental part, p. 933 - 943 (2011/04/23)
Reaction of n-propylamino-N,N-bis(2-methylene-4-tert-butyl-6-methylphenol), H2L1, n-propylamino-N,N-bis(2-methylene-4,6-di-tert-butylphenol), H2L2, and benzylamino-N,N-bis(2-methylene-4-tert-butyl-6- methylphenol), H2L3, with anhydrous ferric chloride in the presence of base yields the products, [FeL1(μ-Cl)]2 (1), [FeL2(μ-Cl)]2 (2) and [FeL3(μ-Cl)]2 (3). In the solid state, these complexes exist as chloride-bridged dimers giving distorted trigonal bipyramidal iron(iii) ions. Reaction of H2L1 with FeBr 3, however, results in the formation of a tetrahedral iron(iii) complex possessing two bromide ligands. The amine-bis(phenolate) ligand is bidentate in this complex and bonds to the iron(iii) ion via the phenolate O-donors. The central amine donor is protonated, resulting in a quaternized ammonium fragment and the iron(iii) centre possesses a negative formal charge. As a result, this complex is zwitterionic and formulated as FeBr2L1H (4). Complex 1 is an air-stable, non-hygroscopic, single-component catalyst for C-C cross-coupling of aryl Grignard reagents with primary and secondary alkyl halides, including chlorides. Good to excellent yields of cross-coupled products are obtained in diethyl ether at room temperature. In some cases where low yields are obtained under these conditions, the use of microwave-assisted heating of the reaction mixture can improve yields. The Royal Society of Chemistry 2011.
