以銅金屬氮異環碳烯車輪烷完成一鍋化的順序連接化學反應

Abstract

我們合成了具有車輪烷結構的NHC-CuI 錯合物，並使其作為立體選擇性的催化劑，來進行銅催化的疊氮化物/炔烴環加成，完成一鍋化的順序連接化學反應。利用套在車輪烷上的大環分子，能讓金屬錯合物選擇性地對體積較小的疊氮化物/炔進行催化。之後通過照光，可以將具有光解基團的大環分子從車輪烷上移去，使啞鈴分子上的NHC-CuI金屬催化中心催化體積較大的疊氮化物/炔，進行點擊反應。透過這樣的策略，我們可以在單個密封瓶中使兩種不同的疊氮化物選擇性地和雙炔分子反應，生成主要的雙三唑產物 (84%)。

We synthesize NHC-CuI complexes with rotaxane architecture, using them as sterically sensitive catalysts for one-pot sequential ligation by copper-catalyzed azide/alkyne cycloadditions. Photolabile and sterically encumbered complexes first catalyze the ligation of less bulky azide/alkyne pairs. Through irradiation with light, the protective macrocyclic components can be removed from the rotaxane structure, and the resulting dumbbell components with NHC-CuI complexes catalyze the second click reaction of bulkier azide/alkyne pairs. Using this approach, we can predominantly obtain a bis-triazole product (84%) from a mixture of two sterically distinct azides and a diyne in a single sealed pot.