the presence of a catalytic amount of Ce(OTf)3, both benzyl and phenyl azides react with a broad range of aryl nitroolefins containing a range of functionalities selectively producing 1,5-disubstituted1,2,3-triazoles in good to excellent yields.
Regioselective Synthesis of 1,5-Disubstituted 1,2,3-Triazoles by Reusable AlCl<sub>3</sub> Immobilized on <font>γ</font>-Al<sub>2</sub>O<sub>3</sub>
作者:Hemmaragala M. Nanjundaswamy、Heidi Abrahamse
DOI:10.1080/00397911.2014.997366
日期:2015.4.18
Abstract There is rapidly growing interest in the synthesis and use of substituted 1,2,3-triazoles. We report an easy and interesting procedure that demonstrates the effectiveness of surface-modified γ-Al2O3, which is reusable, efficient, catalytic, safe, and environmentally acceptable for the regioselective synthesis of 1,5-disubstituted-1,2,3-triazoles via [3 + 2] cycloaddition of phenyl and benzyl
The [3+2] cycloaddition reaction between nitroolefins and alkyl/aryl azides was studied using functionalized silver nanoparticles (FnAgNPs) of average diameter 23 +/- A 1 nm as catalyst produced by the plant extract Protorhus longifolia. We found FnAgNPs to catalyze the reactions efficiently yielding a series of 1,5-disubstituted-1,2,3-triazolines under mild reaction conditions with no side products. The catalytic activity of FnAgNPs was compared with naked AgNPs and FnAgNPs found to be very effective. Except solvents, the whole experiments do not require any chemical/reagent which makes the process green.[GRAPHICS]