One-Step Redox Route to N-Heterocyclic Phosphenium Ions

One-step reactions of the appropriate N-alkyl-, N-cycloalkyl-, and N-aryl-substituted α-diimines with PI3 afforded >80% yields of the triiodide salts of the following N-heterocyclic phosphenium ions, 3 (R1 = t-Bu; R2 = H); 4 (R1 = 2,6-i-Pr2C6H3; R2 = H), 5 (R1 = Mes; R2 = H), 6 (R1 = 2,6-i-Pr2C6H3; R2 = H), and 7 (R1 = cyclohexyl; R2 = H). Treatment of 3 and 6 with NaB(C6H5)4 resulted in virtually quantitative yields of the corresponding [B(C6H5)4]- salts 8 and 9, respectively. The X-ray crystal structures of 3 and 5−9 were determined.将合适的N-烷基、N-环烷基及N-芳基取代的α-二亚胺与三碘化磷（PI3）进行一步反应，可得到如下N-杂环亚鏻离子的三碘化物盐，产率均>80%：化合物3（R¹ = 叔丁基(t-Bu)；R² = H）、化合物4（R¹ = 2,6-二异丙基苯基(2,6-i-Pr₂C₆H₃)；R² = H）、化合物5（R¹ = 均三甲苯基(Mes)；R² = H）、化合物6（R¹ = 2,6-二异丙基苯基(2,6-i-Pr₂C₆H₃)；R² = H）以及化合物7（R¹ = 环己基；R² = H）。将化合物3与6分别与四苯基硼酸钠（NaB(C₆H₅)₄）反应，可分别以近乎定量的产率得到对应的四苯基硼酸根([B(C₆H₅)₄]⁻)盐8与9。此外，测定了化合物3及5~9的X射线晶体结构。