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[摘要]：2,4,6-Trifluoropyridine was diiodinated with a mixture of potassium iodide and periodic acid in sulfuric acid at 55 degrees C to give 2,4,6-trifluoro-3,5-diiodopyridine in 85% yield. Both the starting trifluoropyridine and its 3,5-diiodo derivative readily react with excess sodium azide in dimethyl sulfoxide at room temperature to afford 2,4,6-triazidopyridine and 2,4,6-triazido-3,5-diiodopyridine in high yields. In the N-15 NMR spectra of the triazides, the N-alpha atoms of the alpha- and gamma-azido groups show very differing chemical shifts, which indicates the different reactivity of these groups in 1,3-dipolar cycloaddition, phosphorylation, reduction, thermolysis, and photolysis reactions. |
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