| Abstract
| - Lanthanide(III) catalysts supported on ionexchange resins (Ln-resins) were prepared from Dowex,Amberlite, Amberlyst, and other cation exchange resins. The amountof lanthanides on resinsupports was measured through EDTA titration. The resultsindicated that the lanthanides inaqueous solution exchanged with almost all the cations(H+ or Na+) on the resins to formstableionic complexes between the lanthanides(III) and the resins.The effects of resin types, resin sizes,and lanthanide salts were investigated with a reaction of indole andhexanal in aqueous solutionand with an aldol reaction of benzaldehyde and silyl enol ether inorganic solvents. The studyfound that among ion exchange resins tested Amberlyst XN-1010 andAmberlyst 15 complexedwith lanthanides(III) were the most effective catalysts. Inaddition, the selective Ln-resins wereutilized to catalyze acetalization of aldehydes, aldol reaction offormaldehyde or benzaldehyde inaqueous solution, nucleophilic addition to an imine, allylation of analdehyde, an aza Diels−Alder(DA) reaction, and a ring-opening reaction of an epoxide.Furthermore, glycosylation of alcoholusing glucosyl fluoride as a donor was also promoted with the Ln-resin.Thus, this workdemonstrated potential uses of lanthanide(III) catalysts supportedon ion exchange resins in routineorganic reactions.
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