Forging Molecular Complexity via N-O Bond Cleavage: Synthesis of Structurally Diverse Nitrogen Heterocycles

With the support of the Chemical Synthesis Program in the Division of Chemistry, Professor László Kürti of Rice University is studying the development of reactions to build nitrogen-containing molecules—compounds commonly found in medicines, crop-protection agents, and functional materials. These new synthetic strategies break weak N-O bonds to drive the formation of stronger bonds, use readily available building blocks and avoid reliance on expensive precious metal catalysts or harmful reagents. In addition, Professor Kürti leads a long-standing K–12 outreach program called “Fun with Chemistry,” which reaches over 8,000 students annually in the Houston area. The program promotes STEM education through live demonstrations and hands-on activities. This project focuses on reagent-controlled strategies to construct diverse N-heterocycles by harnessing the cleavage of weak N–O bonds to drive C–C and C–N bond formation. Key approaches include the development of [3,3]-sigmatropic rearrangements of N-alkenyl and N-aryl O-vinylhydroxylamines and O-dihalocyclopropyl hydroxylamines to access fully substituted pyrroles, indoles, and halogenated indolines. Additionally, new intermolecular and intramolecular amination reactions using amphoteric O-sulfonyl hydroxylamines are being explored for their ability to engage both electrophilic and nucleophilic partners. These activities are expanding the toolkit of operationally simple, catalyst-free reactions and providing broadly useful methods for the synthesis of azaheterocycles relevant to pharmaceuticals, agrochemicals, materials science and catalysis. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.