News & Events
Chemistry Seminar - Glenn M. Sammis
Posted on 2017-08-14 in Events
Aug 15, 2017
Target-Inspired Radical Methodology Development
The development of new synthetic technologies for the selective fluorination of organic compounds has increased with the escalating importance of fluorine-containing pharmaceuticals. Traditional methods potentially applicable to drug synthesis rely on the use of ionic forms of fluorine (F– or F+). We have demonstrated that the electrophilic fluorine sources N-fluorobenzenesulfonimide (NFSI)1 and Selectfluor®1 can effectively fluorinate alkyl radicals.2 Continuing research towards utilizing these fluorine atom transfer reagents in synthesis, we have recently developed a transition metal-free methodology that marks the first example of the direct and selective photochemical formation of C-F bonds3, a photocatalytic method utilizing Ru(bpy)32+,4 and xenon difluoride mediated method (Fig. 1).5 These approaches work well for a broad range of alpha-aryloxy substrates using very mild and inexpensive reaction conditions. The details of this work, along new radical synthetic methodology for C-C bond formation, will be discussed.
Fig. 1: Syntheses of Trifluoromethoxy Arenes Using Xenon Difluoride
1. M. Rueda-Becerril, C. Chatalova Sazepin, J. C. T. Leung, T. Okbinoglu, P. Kennepohl, J. -F. Paquin, G. M. Sammis, G. M. J. Am. Chem. Soc. 2012, 134, 4026- 4029.
2. For other early examples of fluorine transfer using Selectfluor®, see: a) Yin, F.; Wang, Z.; Li, Z.; Li, C. J. Am. Chem. Soc. 2012, 134, 10401. b) Barker, T. J.; Boger, D. L. J. Am. Chem. Soc. 2012, 134, 13588. c) Liu, W.; Huang, X.; Cheng, M.-J.; Nielsen, R. J.; Goddard III, W. A.; Groves, J. T. Science 2012, 337, 1322. d) Bloom, S.; Pitts, C. R.; Miller, D. C.; Haselton, N.; Holl, M. G.; Urheim, E.; Lectka, T. Angew. Chem. Int. Ed. 2012, 51, 10580.
3. Leung, J. C. T.; Chatalova-Sazepin, C.; West, J.; Rueda-Becerril, M.; Paquin, J. – F.; Sammis, G. M. Angew. Chem. Int. Ed. 2012, 51, 10804.
4. M. Rueda-Becerril, O. Mahé, M. Drouin, M. B. Majewsky, J. G. West, M. O. Wolf,
G. M. Sammis, J.-F. Paquin J. Am. Chem. Soc. 2013, 136, 2637.
5. Chatalova Sazepin, C.; Binayeva, M.; Epifanov, M.; Zhang, W.; Foth, P.; Amador, C.; Jagdeo, M.; Boswell, B.; Sammis, G. M. Org. Lett., 2016, 18, 4570-4573.
Date: Tuesday, August 15, 2017
Time: 11:00 a.m.
Place: Thorvaldson 205A EVERYONE WELCOME
Chemistry Seminar - Dr. Sanjai Kumar Pathak
Posted on 2019-06-14
Dr. Sanjai Kumar Pathak, Queens College and Graduate Center of CUNY, New York will present a special seminar.
Chemistry Special Seminar - Dr. Claude Spino
Posted on 2019-05-21
Dr. Claude Spino, Universite de Sherbrooke, will present a special seminar at 11:00 a.m. in Thorvaldson 159.
Chemistry Weekly Seminar - PhD Candidate Vankata Garapati
Posted on 2019-04-18
Venkata Garapati, PhD Candidate, will present a seminar at 10:30 a.m. in Thorvaldson 159.
Chemistry Weekly Seminar - Dr. Rob Britton
Posted on 2019-03-14
Dr. Robert Britton, Department of Chemistry, Simon Fraser University, will present a seminar at 4:00 pm in Thorvaldson 110.
Special Seminar - Dr. Darren Derksen
Posted on 2019-03-06
Dr. Darren Derksen will present a Special Seminar at 11:30 am in Geology 261
Special Seminar - Dr. Amy Stevens
Posted on 2019-02-08
Dr. Amy Stevens, Department of Chemistry, will present a seminar