Photoactivation of Aryl Tetrazoles: Governing Nitrile Imine Fate Through Reactivity‐Based Applications

Photoactivation of aryl tetrazoles represents a powerful strategy for the spatiotemporally controlled generation of nitrile imines (NIs), highly reactive 1,3-dipoles formed via photolytic cycloreversion with concomitant nitrogen extrusion. These transient intermediates exhibit versatile reactivity, engaging in various transformations through both intermolecular and intramolecular pathways including dipolar cycloadditions and nucleophilic additions. Each specific pathway and efficiency is critically governed by the reaction environments: the presence (or strategic design) of suitable interception partners or tethered functional groups. This review systematically outlines the fundamental reactivity of photogenerated NIs in a spatiotemporally controlled manner and emphasizes strategic control over their reaction pathways. Furthermore, it highlights their advanced applications, spanning photochemical biological labeling, protein manipulation, high-resolution bioimaging, photo-responsive polymers, and material surface engineering. By connecting fundamental principles with diverse applications, this work aims to offer a comprehensive perspective on harnessing the reactivity of photogenerated nitrile imines for precision synthesis and functional material design.