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Professor Samir Zard

Samir Z. Zard was born in 1955 in Ife, Nigeria. His training as a chemist started at the American University of Beirut, then at Imperial College, London, and finally at the Université Paris-Sud, France, where he received his doctorate under the supervision of Professor Sir Derek Barton, FRS and Nobel Prize Laureate. He now has the rank of Director of Research - Exceptional Class in the CNRS and Professor of Organic Chemistry at Ecole Polytechnique. His main research interests concern the study and development of new reactions and processes, with a particular emphasis on the chemistry of organosulfur and organofluorine derivatives, alkynes, nitro compounds, and radicals. Work in the last area has resulted in the powerful RAFT-MADIX process for controlled polymerization, which allows the industrial production of block polymers. He has authored or co-authored 260 papers and 32 patents, and presented nearly 400 invited lectures and seminars at national and international meetings and universities.

He wa a Fellow of the Chemistry Research Promotion Center of the National Science Council of Taiwan in 1997, Astra-Zeneca USA Lecturer in 1999, Sherbrooke-Bohringer Ingelheim Canada Lecturer in 2000, Bürgenstock Lecturer in 2001, Merck Sharpe & Dohme Lecturer in 2003, Fellow of the Japan Society for the Promotion of Science in 2004, * Novartis-UC Irvine Lecturer in 2008, Novartis-Berkeley Lecturer in 2008, Bristol-Myers Squibb-Scripps Institute Lecturer in 2008.

His scientific awards and honors include the 1992 Prize of the Organic Chemistry Division of the French Chemical Society, the 1995 Clavel-Lespiau Prize of the French Academy of Science, the Rhodia Prize in 2000, the Dargelos Prize in 2006, the Novartis Chemistry Lectureship for 2006-2007, the Silver Medal of the CNRS in 2007, the Presidency of the Bürgenstock Conference in 2007. In 2003, he was promoted Chevalier des Palmes Académiques and, in 2007, received the Croix de Chevalier de la Légion d’Honneur.

Sample of Academician's Research

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Xanthates (dithiocarbonates) are a general and efficient source of various radicals: alkyl, acyl, alkoxycarbonyl, alkoxythiocarbonyl, triphenylstannyl, etc... These radicals can be obtained by homolytic rupture (after chemical or photochemical initiation) of either the C-O bond ("Barton-McCombie type radical") or the C-S bond.

Unlike most of the other radical methodologies, xanthates allow intermolecular trapping of the intermediate radical species by non-activated olefins . This feature enabled Prof. Zard and his co-workers to achieve a short and convergent total synthesis of (±)-matrine , a tetracyclic alkaloid.

The main advantage of this method relies on the fact that the adduct is a xanthate too. This allows to move on to new radical reactions with different traps, and to build complex systems from very simple starting materials.

In some cases, particularly with xanthates coming from carbohydrates, a reduction can be performed through a catalytic hydrogen transfer from cyclohexane. This transformation is probably the most spectacular proof of polar effects in radical chemistry.
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