Synthetic Chemistry of Organic Dyes toward Controlled Near-Infrared Light-Mediated Reactions

Near-infrared (NIR) light (specifically 700-1000 nm) has garnered significant attention in recent years. Even though 52% of solar energy is infrared light, the utilization of energy in this region remains an area for improvement because most current natural and artificial materials do not interact with it. Organic synthesis provides a wide array of organic molecules. Therefore, developing novel dyes and pigments through synthetic organic chemistry is crucial to optimize the utilization of NIR light. Phthalocyanines and related macrocycles are well-known artificial dyes in modern materials chemistry. We are focusing on novel synthetic methods for phthalocyanines, creating novel phthalocyanine-based NIR chromophores, and developing novel NIR light-mediated molecular transformations using phthalocyanine catalysis. This article presents our recent findings on the chemoselective synthesis of photofunctional materials with intense NIR light interactions. The development of these materials requires precise control of the photoexcited state. Through fine-tuning NIR dyes, we have achieved highly robust photosensitizing agents, NIR light-mediated photodynamic therapy, and NIR light-driven organic reactions. Moreover, novel reaction environments with photofunctional materials can propose new applications for NIR light utilization. These achievements create further opportunities for the flexible application of NIR light.