环张力促进的迭氮-炔环加成反应

In recent years, strain-promoted azide-alkyne cycloaddition (SPAAC) reaction has been widely used in many fields such as biomedicine and materials science due to its high efficiency, rapidity, high selectivity, and bioorthogonality. SPAAC reaction does not require additional stimuli such as light, heat, ultrasound or catalysts. The driving force of the reaction comes from the active cyclic alkynes with high strain. Therefore, the rational design of the cycloalkynes is the key to the SPAAC reaction. In this review, the stability and reactivity of cycloalkynes with different ring numbers are discussed, and the stable cycloalkynes participating in SPAAC smoothly as well as their second-order reaction rate constants in the SPAAC reaction are summarized. The research progress in the preparation methods of representative cyclic alkynes that are currently widely used is also introduced. Moreover, the application, challenge and future outlook of SPAAC without copper catalysis are discussed and prospected.