Amines indium triflate

At a loading as low as 0.5 mol%, indium triflate catalyzes the three-component coupling reaction between aldehydes, amines, and Danishefsky s diene to afford tetrahydropyridine derivatives (Scheme 8.106) [138]. In fhe presence of indium triflate, 3,4-dihydro-2H-pyran reacts with in sitw-generated chromone Schiff s bases to give the endo cycloadducts (Scheme 8.107) [139]. 

Indium triiodide catalyzes transesterification processes, e.g. the acylation of alcohols or amines and the conversion of THP ethers to acetates (Scheme 8.143) [187]. Indium triflate is also an efficient catalyst for the acylation of alcohols and amines (Scheme 8.144) [188]. Carboxylates are hydrolyzed to the corresponding carboxylic acids in high yield by microwave-assisted reaction on the surface of moistened silica gel in the presence of indium triiodide (Scheme 8.145) [189]. 

Gao, B. Wen, Y. Yang, Z. Huang, X. Liu, X. Feng X. (2008) Asymmetric ring opening of meso-Epoxides with aromatic amines catalyzed by a new proline-based N,N -dioxide-indium tris (triflate) complex,/t/v. Synth. Catal, 350 385- 390. 

Aminoalkyl and Related Acids. - Further development of the classical three component approach to aminoalkylphosphonates (the Kabachnik-Fields reaction) has been reported. The reaction of aldehydes, hydroxylamines and dimethyltrimethylsilyl phosphite using lithium perchlorate/diethyl ether as a catalyst gives N-trimethylsilyloxy-a-aminophosphonate derivatives. The catalytic activities of various lanthanide triflates as well as indium trichloride have been examined for the Kabachnik-Fields type reactions of aldehydes, amines and the phosphorus nucleophiles HP(0)(0Et)2 and P(OEt)3 in ionic liquids. TaCb-Si02 has been utilized as an efficient Lewis acid catalyst for the coupling of carbonyl compounds, aromatic amines and diethyl phosphite to produce a-... 

The aza-Diels-Alder reaction of imines with diene of Danishefsky is an important route to 2,3-dihydro-4-pyridones. A number of Lewis acids have been used to catalyze the reaction in organic solvents. In water the reaction was realized by acid catalysis via iminium salts or by Bronsted acids. The montmorillonite K-10 catalyzed this cycloaddition in water or in aqueous acetonitrile in excellent yield. Recently Kobayashi has performed the reaction in water at room temperature under neutral conditions in two (imine - - diene) or three (aldehyde -b amine -b diene) component versions by using sodium triflate as catalyst. Imine intermediates from the indium-mediated reaction, in aqueous medium at 50° C, between aromatic nitro compounds and 2,3-dihydrofuran undergo aza-Diels-Alder cycloadditions to give tetrahydroquinoline derivatives in good overall yields. ... 

Aryl sulfonamides can be found in a range of biologically important molecules. Such compounds are generally synthesized from the parent arene in a two-step process of chlorosulfonyla-tion with CISO3H and then reaction with an amine. In a one-step process, indium(III) triflate was found to be the only efficient catalyst for the formation of AfA -dialkylsulfonamides from the reaction of an arene with a dialkylsulfamoyl chloride. As illustrated, the catalytic reaction of dimethylsulfamoyl chloride with toluene in refluxing dichloroethane afforded the sulfonamide product in good yields (eq 6). 

The Frost group has demonstrated the use of indium(III) triflate as a catalyst for hetero Diels-Alder reactions. In the presence of just 0.5 mol % of catalyst, the imino Diels-Alder reaction of an imine and Danishefsky s diene provides the product in excellent yields (eq 16). A three-corrponent coupling of an aldehyde, amine, and diene was also reported. 

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