Kumar Nitish, Sharma Tanu, Thakur Nirbhay, Jain Rahul, Sinha Narayan
School of Chemical Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh, 175075, India.
Chemistry. 2025 May 8;31(26):e202500365. doi: 10.1002/chem.202500365. Epub 2025 Apr 14.
Photocatalysis emerges as an efficient and versatile tool for the preparation of organic compounds via the development of new methodologies and new photosensitizers. Mostly UV and blue light irradiation are used for such reactions. Red light is low-energy light, it is less harmful and has more penetration depth. Hence red light-driven photocatalysis would be more suitable for preparing value-added products. Red-absorbing photosensitizers are mostly based on rare and expensive metals. In this review, we describe the recent developments on Earth-abundant transition metal-based photosensitizers (W(0), Mo(0), Cr(0), Fe(III), Cu(I), Zn(II)) and their applications in red light-driven photocatalysis. Photocatalysis using both electron transfer and energy transfer processes is discussed. Three different red light-induced reactions such as direct monophotonic excitation, sensitized triplet-triplet annihilation upconversion (sTTA-UC), and dual red light photocatalysis are presented. Various organic transformations such as reductive dehalogenation and detosylation, reduction of diazonium salts, C─C coupling via C─H activation, oxidation of aryl boronic acids to phenols, polymerization reactions, cross dehydrogenative couplings, α-cyanation of tertiary amines, Barton decarboxylation have been carried out using abundant photosensitizers and red light.
通过开发新方法和新型光敏剂，光催化成为制备有机化合物的一种高效且通用的工具。此类反应大多使用紫外线和蓝光照射。红光属于低能量光，危害较小且穿透深度更大。因此，红光驱动的光催化更适合用于制备增值产品。吸收红光的光敏剂大多基于稀有且昂贵的金属。在本综述中，我们描述了基于地球上储量丰富的过渡金属的光敏剂（W(0)、Mo(0)、Cr(0)、Fe(III)、Cu(I)、Zn(II)）的最新进展及其在红光驱动光催化中的应用。讨论了同时使用电子转移和能量转移过程的光催化。介绍了三种不同的红光诱导反应，如直接单光子激发、敏化三线态 - 三线态湮灭上转换（sTTA - UC）和双红光光催化。使用储量丰富的光敏剂和红光进行了各种有机转化反应，如还原脱卤和脱甲苯磺酰基、重氮盐的还原、通过C─H活化进行C─C偶联、芳基硼酸氧化为酚、聚合反应、交叉脱氢偶联、叔胺的α - 氰化、巴顿脱羧反应。
