Triftosylhydrazone: A Powerful Reagent for Carbene Chemistry
Thurs., Dec. 25, 2025, 9:15 am (China Standard Time)
About our Virtual Chemistry Lecture on Triftosylhydrazone
In this talk, Professor Xihe Bi shared the story behind his team’s work on carbene transfer chemistry and how a simple change in reagent design opened up a surprising range of new possibilities.
Carbene transfer reactions have long been essential tools in organic synthesis, but most methods still rely on α‑diazocarbonyl compounds, since other diazo species tend to be unstable and can easily dimerize instead of reacting productively. Chemists have tried to work around this using tosylhydrazones as more accessible carbene precursors, but these traditionally require high temperatures—often above 70 °C—to break down into diazo compounds. That makes them difficult to use in reactions where temperature control is important.
In 2018, Professor Bi’s group identified triftosylhydrazone, a reagent that behaves very differently. Thanks to the steric and electron‑withdrawing effects of its ortho‑CF₃ group, it can generate diazo species effortlessly—even at –40 °C. This unusual combination of stability and reactivity has allowed the team to use it as a practical stand‑in for challenging intermediates like gaseous diazomethane or highly electrophilic silver carbenes.
During the talk, Professor Bi walked through how this reagent was discovered, how it works, and the wide range of carbene transfer reactions it enables. He also touched on its emerging role in single‑atom skeletal editing of heteroarenes, an exciting direction that is expanding what chemists can accomplish in late‑stage molecule modification.
Overall, the session offered a clear, engaging look at how one thoughtfully designed reagent can reshape long‑standing synthetic methods—and open up new avenues for research and innovation.
About our Speaker
Prof. Xihe Bi
Prof. Bi is a professor of organic chemistry at the Department of Chemistry, Northeast Normal University, as well as a distinguished professor under the Ministry of Education’s “Changjiang Scholars Award Program“. His primary research focuses on carbene chemistry. He designed and developed a novel o-trifluoromethylbenzenesulfonylhydrazone, which has been named “Triftosylhydrazone“. This innovation successfully resolves the issue of the excessively high decomposition temperature associated with traditional p-methylbenzenesulfonylhydrazones (Tosylhydrazones), which limited their applicability in temperature-sensitive reactions. Triftosylhydrazone has emerged as an efficient precursor compound for carbene chemistry. Based on this advancement, he has established a series of organic chemical reactions that demonstrate high efficiency and selectivity under mild conditions, significantly propelling the progress of sulfonylhydrazone carbene chemistry. To date, his research group has published over 160 papers in internationally renowned journals, including Nat. Chem., Nat. Commun., Chem., J. Am. Chem. Soc., Angew. Chem., Acc. Chem. Res., Chem. Rev., and Chem. Soc. Rev. Professor Bi has led a number of scientific research projects, including key initiatives supported by the National Natural Science Foundation of China. Additionally, he has received several prestigious accolades, such as the First Prize of the Jilin Province Natural Science Award and the WuXi AppTec Life Chemistry Research Award.
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.