Cu(OTf)2‑Catalyzed Selective Arene C–H Bond Hydroxylation and Nitration with KNO2 as an Ambident O- and N‑Nucleophile via a Cu(II)–Cu(III)–Cu(I) Mechanism

Cu(OTf)2-catalyzed selective arene C–H bond hydroxylation and nitration reactions of azacalix[1]arene[3]pyridines were achieved using KNO2 as an ambident O- and N-nucleophile under very mild aerobic conditions to yield functionalized azacalixaromatics. The reaction, which selectivity between hydroxylation and nitration was modulated by the reaction medium employed, proceeded through a Cu(II)–Cu(III)–Cu(I) mechanism.

以亚硝酸钾（KNO2）作为兼具O与N亲核位点的两可亲核试剂（ambident O- and N-nucleophile），在极为温和的有氧条件下，成功实现了三氟甲磺酸铜(II)（Cu(OTf)2）催化的氮杂杯[1]芳烃[3]吡啶的芳烃C–H键选择性羟基化与硝化反应，得到功能化的氮杂杯芳烃（azacalixaromatics）类产物。该反应的羟基化与硝化选择性可通过所选用的反应介质进行调控，其反应历程遵循Cu(II)–Cu(III)–Cu(I)催化循环机理。