Synthesis Of Diaryl Bis(1,2,3-triazole)s Based On Huisgen Reaction

The1,2,3-triazoles, as important heterocyclic compounds, has been known fortheir unique chemical properties and medicinal worth proved by lots of research andexperiments. Due to their unique chemical and structural properties, they havereceived much attention over the past decades. Up to now, they have not been isolatedfrom natural products. In the methods for synthesis of1,2,3-triazoles.1,3-Dipolarcycloaddition of azides to alkynes is the most important one of them, which was firstproposed and studied by Rolf Huisgen. Then Sharpless developed the reaction forsynthesis of1,2,3-triazoles.Sharpless and co-workers previously noticed such minor amounts of by-productsbis（1,2,3-trazole）s and, without reporting their characterization. Then Kevin andFiandanese optimized the reaction condition on that basis to synthesis ofbis（1,2,3-trazole）s. But their reactions exist some inadequate, just as low yield, manyby-products and hard to get starting materials. There have been some reports about thesynthesis of bis（1,2,3-trazole）s with terminal alkynes as starting materials, but thesynthesis of bis（1,2,3-trazole）s with unterminal alkynes has little attention until now.The synthesis result of this paper as follows:1. The synthesis of symmetry aryl conjugate diynes: a series of aromatic amine wereconverted to halogen substituted aryl compounds via diazotization, and then bySonogashira coupling reaction, halogen substituted aryl compounds reacted withtrimethylsilylethyne, ethyne motif was involved. Trimethylsilyl group was removed togive the corresponded terminal alkynes. Finally, terminal alkynes were converted tosymmetry aryl conjugate diynes by self coupling reaction: Glaser reaction.2. The synthesis of4,4’-Diaryl-5,5’-bi-1,2,3-triazoles and4,5-disubstituted-1,2,3-triazole: As starting materials, symmetry aryl conjugate diynes reacted withsodiumazide via Huisgen1,3-Dipolar cycloadditon, in different conditions, a seriesof4,4’-Diaryl-5,5’-bi-1,2,3-triazoles and4,5-disubstituted-1,2,3-triazole compoundswere obtained in a good yield.The novel compounds were confirmed by¹H NMR,¹³C NMR, IR and MS.