One-step Amination by Parent Nitrenium Ion and Alkylnitrenium Ion

在芳烃-三氟乙酸中，由1-氨基吡啶和s -氨基磺鎓盐及其衍生物光解生成亲本、烷基、二烷基和脂环硝基离子。光解反应通过单线态氮离子生成芳香n取代产物，通过三重态氮离子生成吸氢产物。通过Hammett图的rho -2.1，排除了氨基自由基或胺离子的作用机理，以及重原子或氧分子的作用机理。反应盐的阳离子和阴离子部分变化对反应性的影响表明，氮离子既与吡啶或硫化物杂原子的未共享电子对相互作用，也与Gegen阴离子相互作用。因此单线态氮离子通过这种相互作用得到稳定。单线态氮离子也通过与18-冠-6的相互作用得到稳定；冠醚的存在提高了氮离子取代的产率。氮离子对苯甲醚较好的邻攻作用，很好地支持了氮离子与苯甲醚氧原子之间的相互作用。重原子溶剂和氧分子促进了单重态氮离子向三重态氮离子的S-T转化。越稳定的单线态氮离子对S-T转化的促进作用越显著。由于单重态和三重态之间的快速平衡，具有较低单重态-三重态能隙的二烷基或脂环氮离子在良好的给氢体（如甲苯或三甲基）存在下发生快速的S-T转化。另一方面，三态母体氮离子与。Gegen阴离子I^-可与萘或菲通过叠氮中间体的扩环反应生成新的化合物：1H-和9H- 1 -苯并氮或9H-和11h -二苯并氮[d，f]。

Parent, alkyl, dialkyl, and alicyclic nitrenium ions were generated from photolyses of 1-aminopyridinium and S-aminosulphonium salts and the derivatives in arene-trifluoroacetic acid. The photolyses gave aromatic N-substitution pro- ducts via the singlet nitrenium ions and hydrogen abstraction products via the triplet nitrenium ions.The mechanism was suggested by rho -2.1 for Hammett plot, an exclusion of a mechanism through an amino radical or aminium ion, and an effect of heavy atom or oxygen molecule. The result altering the reactivity upon the change of cationic and anionic portions of the reactant salt shows that the nitrenium ion interacts with both the unshared electron pair of the heteroatom of pyridine or sulphide and the Gegen anion. Thus the singlet nitrenium ion is stabilised by this interaction. The singlet nitrenium ion is also stabilised by interaction with 18-crown-6; the yield of N-substitution by the nitrenium ion was increased in the presence of the crown ether. The preferable ortho-attack of the nitrenium ion on anisole well supports the interaction between the nitrenium ion and the oxygen atom of anisole.The S-T conversion of the singlet into the triplet nitrenium ion is promoted by heavy atom solvent and oxygen molecule. The more stabilised singlet nitrenium ions can undergo the more predominant promotion of the S-T conversion. The di- alkyl or alicyclic nitrenium ion having a lower singlet-triplet energy gap than the alkyl or parent nitrenium ion undergoes a fast S-T conversion in the presence of a good hydrogenatom donor such as toluene or mesitylene due to a fast equilibrium between the singlet and triplet states.On the other hand, the triplet parent nitrenium ion with the.Gegen anion I^- is allowed to react with naphthalene or phenanthrene to yield novel compounds, 1H- and 9H-l-benzazepines or 9H- and 11H-dibenzo[d,f]azepines, via the ring- expansion of aziridine intermediates.