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Dr. Hélène Lebel

 

Helene Lebel Photo




 

Biography

Hélène Lebel received her B.Sc. degree in biochemistry from the Université Laval in 1993. She conducted her Ph.D. studies in organic synthesis at the chemistry department of the Université de Montréal under the supervision of professor André B. Charette as a 1967 Science and Engineering NSERC Fellow. In 1998, she joined the research group of professor Eric Jacobsen at Harvard University as a NSERC Postdoctoral Fellow. She started her independent career in 1999 at the Université de Montréal and has been promoted to the rank of Associate Professor in 2005 and as Full Professor in 2010. Professor Lebel has already received a number of academic honors, including the Enantioselective Synthetic Chemistry Research Award in 2005, the Johnson & Johnson Focused Funding Grant Award in 2008 and the Merck Frosst Centre for Therapeutic Research Award in 2009. She currently holds the Canada Research Chair in Organometallic Catalysis. The major aim of her research program is to develop new synthetic methodologies in organic chemistry to produce C-C and C-N bonds.

Abstract

Metal Nitrenes in Amination Reactions

 
Département de chimie, Université de Montréal,
2900 Boul. Edouard Montpetit, Montréal, Qc, Canada, H3T 1J4
E-Mail : umontreal.ca


The catalytic formation of C-N bond via the direct functionalization of C-H bonds using metal nitrenes will be presented. The use of N-tosyloxycarbamates with rhodium dimer catalysts allowed the intra- and intermolecular C-H insertion reactions in high yields. This new methodology allows the amination of ethereal, benzylic, tertiary, secondary and even primary C H bonds. The intramolecular reaction provides an interesting route to various substituted oxazolidinones. The intermolecular reaction produces Troc-protected amines which are isolated with moderate to excellent yields and are easy to cleave to produce the corresponding free amine. The same catalytic system could be used to perform intra- and intermolecular aziridination reactions. Recent results regarding stereoselective amination reactions with novel N-tosyloxycarbamates and chiral rhodium(II)carboxylate catalysts will be discussed.