N-Unsubstituted indazoles 3 and 1-arylindazoles 4 are readily available in good to high yields through [3+2] cycloaddition of 2-(trimethylsilyl)aryl triflates 1 and diazo compounds in the presence of KF or CsF under mild reaction conditions. Furthermore, we found that azomethine imides also underwent cycloaddition reaction with 2-(trimethylsilyl)phenyl triflates (1a) in the presence of KF to afford indazolone derivatives 6 in moderate yields.
N-未取代吲唑3和1-芳基吲唑4可通过2-(三甲基硅基)芳基三氟甲烷磺酸酯1和重氮化合物在KF或CsF存在下在温和反应条件下进行[3+2]环加成反应,以良好至高产率方便获得。此外,我们发现偶氮亚甲基亚胺也可在KF存在下与2-(三甲基硅基)苯基三氟甲烷磺酸酯(1a)发生环加成反应,得到吲唑酮衍生物6,产率中等。