Home / Department / Seminars & Events / Lawrence Sita

Lawrence Sita

Lawrence Sita

Tue, Oct. 17, 2017, 4:30pm
Edward C. Taylor Auditorium, Frick B02
Host: Brad Carrow

Redesigning Synthetic Nitrogen Fixation


 The development of new energy-efficient and atom-economical chemical technologies that can be used for the production of high-value industrial chemicals through the ‘chemical fixation’ of inexpensive and abundant small molecule feedstocks (e.g., N2, CO2, CO, and S8) must be made in the near term in order to meet the demands of a global population that is expected to increase by an additional 3 to 4 billion people within only the next 50 years.  In this regard, the century-old Haber-Bosch process, which converts N2 and H2 under high temperature and pressure into NH3 on a staggering volume of 140 million metric tons per year, currently consumes up to 5% of the world’s energy and it generates an equal quantity of CO2 to provide the required amount of H2

This talk will present recent results obtained in our quest to establish new paradigms and chemical processes that can be used for the transition-metal-mediated conversion of N2 into higher-value nitrogen-containing products under near ambient conditions.  Specific examples include complete chemical cycles for the conversion of N2, CO2 and R3SiCl into trialkylsilyl isocyanates (R3SiNCO),1,2 and more recently, the chemoselective conversion of N2, R3SiCl and “H2O” into bis(trialkylsilyl)amines, (R3Si)2NH.  Future directions for our research with these alternative synthetic nitrogen fixation schemes will also be discussed.


Keane, A. J.; Farrell, W. S.; Yonke, B. L.; Zavalij, P. Y.; Sita, L. R. Angew. Chem. Int. Ed. 2015, 54, 4269.
Duman, L. M.; Farrell, W. S.; Zavalij, P. Y.; Sita, L. R. J. Am. Chem. Soc. 2016, 138, 14856.