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It is widely acknowledged that there is a growing need for more environmentally acceptable processes in the chemical industry. This trend towards what has become known as ‘Green Chemistry’ or ‘Sustainable Technology’ necessitates a paradigm shift from traditional concepts of process efficiency, that focus largely on chemical yield, to one that assigns economic value to eliminatingwaste at source and avoiding the use of toxic and/or hazardous substances.
This concept is embodied in the 12 Principles of Green Chemistry which can be paraphrased as: 1)Waste prevention instead of remediation 2) Atom efficiency 3) Less hazardous/toxic chemicals 4) Safer products by design 5) Innocuous solvents and auxiliaries 6) Energy efficient by design 7) Preferably renewable raw materials 8) Shorter syntheses (avoid derivatization) 9) Catalytic rather than stoichiometric reagents 10) Design products for degradation 11) A nalytical methodologies for pollution prevention 12) Inherently safer processes.

Is Selenium toxic ?
There can be no doubt that selenium-containing organic molecules have played and continue to play an important role in biology and medicine. The mythology surrounding the "high toxicity" of organic selenides, which itself can be traced to the voyages of Marco Polo, and, more recently, the American Civil War, has largely been dispelled, and a wide range of organic selenides are now accepted as useful antioxidants, antiinflammatory agent antibiotics and anti-viral agent.
Glutathione peroxidase (GSH-Px) is a mammalian selenoenzyme that catalyses the reduction of a wide variety of hydroperoxides which are known to generate highly-reactive oxygen radicals that destroy key biological molecules and cause damage to cell membranes. The activity of GSH-Px is principally due to the redox chemistry surrounding the selenocystine residue found in the active site of the enzyme.
from C.H. Schiesser Arkivoc 2001

Is possible to move Selenium Chemistry forward Green Chemistry ?
Over the last thirteen years many important chemical transformations were efficiently achieved using organoselenium intermediates. These reactions can be realized using mild conditions and are usually characterized by high chemio regio and stereoselectivity. During the last ten years, the introduction of some optically pure selenenylating reagents allowed to use this kind of chemistry in asymmetric synthesis. Probably as consequence of the feared toxicity for a long time selenium chemistry has been developed without considering the paradigm of the sustainability and of the green chemistry. Nevertheless several examples reported by Tiecco et al. demonstrated that organoselenium compounds can be efficiently used as catalysts in several chemical transformations.

Our efforts are actually directed on realize new and more efficient selenium catalyzed convertion using room temperature and non conventional solvents. In several cases these new approaches lead to results that are better than those conventionally reported in litterature. To optimize some reaction we are also investigating new and more eco-friendly reductants and oxidants as well as new selenenylating reagents to prepare rispectively nucleophilic and electrophilic species. As a part of the project NMR investigations on the step of the addition to double bonds, using NMR diffusion analysis, will help us to understand the mechanism and the nature of the intermediate species, allow us to better disign the processes.

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