Photocatalytic Reactivity of Zwitterions
Capabilities
Presented: August 28, 2025
About our Virtual Chemistry Lecture on Photocatalytic Reactivity of Zwitterions
Direct functionalization of aliphatic C–H bonds represents a powerful strategy for constructing complex molecules from simple, readily available precursors. In this lecture, Prof. Kohsuke Ohmatsu presented his lab’s pioneering work on expanding the scope of photocatalytic hydrogen atom transfer (d-HAT) reactions using novel zwitterionic nitrogen-centered radical precursors.
Traditional d-HAT catalysis has relied heavily on oxygen-centered radicals derived from aromatic ketones, xanthene dyes, and metal oxo complexes. However, these systems limit the diversity of accessible catalysts. Prof. Ohmatsu’s team has developed a new class of nitrogen-centered radicals—amidate-based zwitterions—that overcome the photoreactivity limitations of conventional nitrogen-containing scaffolds. These innovative structures feature a stable charge-separated ground state and a photoactive cationic moiety, enabling efficient generation of open-shell species capable of engaging in selective C–H activation.
This approach opens new avenues for catalyst design, offering enhanced control over polarity and steric effects—key factors in achieving selective and efficient bond activation. The lecture delved into the mechanistic insights and molecular design principles that underpin this breakthrough, highlighting its implications for sustainable synthesis and molecular innovation.
About our Speaker
Prof. Kohsuke Ohmatsu
Prof. Ohmatsu is a Professor in the Department of Chemistry at Keio University in Yokohama, Japan. He earned his B.Sc. (2003) and Ph.D. (2008) from Kyoto University, and held academic positions at Nagoya University from 2008 to 2024, progressing from Assistant Professor to Associate Professor. In 2024, he joined Keio University as a full Professor.
About the Virtual Chemistry Lecture Series
Pharmaron’s monthly Virtual Lecture Series, launched in July 2020, provides our team and partners with online educational opportunities. World-class academic researchers are invited to present novel research related to synthetic and medicinal chemistry through this virtual forum. The lectures have been insightful and very well received by the audience and have contributed to cultivating a vibrant learning culture at Pharmaron.