“The most fundamental and lasting objective of synthesis is not production of new compounds, but production of properties”.[1] This George Hammond’s statement which may seem evident, should, in my opinion, be the driving force for synthetic chemists in general and perhaps even more for polymer chemists who are often closer to applied science. The last two decades have been particularly important for polymer chemistry with the invention of living/controlled radical polymerization techniques[2] which enable relatively easy synthesis of well-defined functional polymeric architectures. Since 2001, “click chemistry” an umbrella term coined by Barry Sharpless[3] to designate a family of near perfect chemical reactions has been the subject of intense research in all fields of chemistry. This click chemistry has proven to be a very valuable tool to prepare highly functional polymers. In this seminar I will present my contribution to the field. Indeed, combining the copper-catalyzed Huisgen cycloaddition of azide and alkynes (CuAAC)[4] or the more recently rediscovered thiol-ene[5] and thiol-yne[6] reactions with controlled polymerization techniques such as ATRP or RAFT, is a very efficient method to prepare macromonomers and polymeric biomimics such as linear glycopolymers and hyperbranched glycopolymers.[7] For all the advantages presented by click chemistry and the “hype” it has created within the polymer chemistry community, it is important to notice that click chemistry may not be as perfect as it is often claimed to be. Examples of potential very detrimental and often over-looked side reactions will therefore also be discussed.[8]
References
1. George S. Hammond, Norris Award Lecture, 1968.
2. (a) Matyjaszewski, K.; Xia, J. Chem. Rev. 2001, 101, 2921-2990. (b) Hawker, C. J.; Bosman, A. W.; Harth, E. Chem. Rev. 2001, 101, 3661-3688. (c.) Perrier, S.; Takolpuckdee, P. J. Polym. Sci. Part A: Polym. Chem. 2005, 43, 5347-5393.
3. Kolb, H. C.; Finn, M. G.; Sharpless, K. B. Angew. Chem. Int. Ed. 2001, 40, 2004.
4. (a) Rostovtsev, V. V.; Green, L. G.; Fokin, V. V.; Sharpless, K. B. Angew. Chem. Int. Ed. 2002, 41, 2596. (b) Tornoe, C. W. ; Christensen, C.; Meldal, M. J. Org. Chem. 2002, 67, 3057.
5. Kade, M. J.; Burke, D. J.; Hawker, C. J. J. Polym. Sci. Part A: Polym. Chem. 2010, 48, 743-750.
6. Chan, J.; Hoyle, C.; Lowe, A. J. Am. Chem. Soc. 2009, 131, 5751-5753.
7. (a) Mantovani, G.; Ladmiral, V.; Tao, L.; Haddleton, D.M. Chem. Commun. 2005, 2089-2091. (b) Ladmiral, V.; Mantovani, G.; Clarkson, G. J.; Cauet, S.; Irwin, J.L.; Haddleton, D.M. J. Am. Chem. Soc. 2006, 128(14), 4823-4830. (c.) Semsarilar, M.; Ladmiral, V.; Perrier, S. Macromolecules 2010, 43, 1438-1443.
8. Ladmiral, V.; Legge, T. M.; Zhao, Y.; Perrier, S. Macromolecules 2008, 41(18), 6728-6732.
Contact local ICGM : Bruno Améduri (équipe IAM)