Visible Light-Driven Cooperative DPZ and Chiral Hydrogen-Bonding Catalysis

What is the most favorite and original chemistry developed in your research group? The visible light photosensitizer DPZ. How did you get into this specific field? Could you please share some experiences with our readers? Since I began my postdoctoral work at NUS, chiral hydrogen-bonding catalysis, an important branch of asymmetric organocatalysis, has become the general area of focus of my research. To broaden the applications of this strategy, I proposed to exploit photocatalysis to generate highly reactive radical intermediates, thus overcoming the current limitations in both reaction and substrate types stemming from the low energy of hydrogen-bonding interactions. The development of highly efficient organophotocatalysts and explorations of transition metal-free cooperative photocatalysis and chiral hydrogen-bonding catalysis have therefore been my research focus since 2013. My students and I strive to follow the saying stick to the research direction, thoroughly understand the scientific challenges, and face those challenges with optimism and determination. What is the most important personality for scientific research? To do independent, original, ground-breaking and useful chemistry. What are your hobbies? Playing basketball, slow long distance running and reading. How do you maintain a balance between research and family? Having the understanding and support of my family is the most important thing since scientific research requires a large investment of time. Who influences you the most in your life? My parents. Chiral H-bonding catalysis is a powerful platform for asymmetric synthesis. Nevertheless, the rather low energy of hydrogen-bonding interactions has inspired the development of generic platforms with high reactivity, thus effectively expanding the utility of this platform by enabling the use of more kinds of readily accessible feedstocks as substrates and providing new, direct and mild synthetic approaches. To this end, we have developed a transition metal-free cooperative photocatalysis and chiral hydrogen-bonding catalysis platform by devising a highly efficient organophotosensitizer, DPZ. A series of important asymmetric transformations, in which the stereocentres were formed via either ionic-type or radical- type bond-forming pathways, have been developed. The successful development of several novel enantioselective protonation reactions and the construction of all-carbon quaternary stereocentres via highly reactive radical coupling reactions robustly demonstrate the excellent catalytic ability of both DPZ as a photocatalyst and the flexible dual catalyst system.