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Using ?-diazo-?-ketoesters as reagents and combinations of CpRu fragments and diimine ligands as catalysts, a series of original transformations have been obtained that can be rationalized by the formation of metal carbenes and metal-bound ylide intermediates. Interesting 1,3-dioxole, enol-acetal and 1,4-dioxene motifs are obtained directly when the reactive mixture is reacted in presence of aldehydes or ketones, THF and epoxides.

This article describes the situation of Department of Organic Chemistry in the year of the 450th anniversary of the University of Geneva.

Enantiopure (diastereomeric) doubly bridged biphenyl azepines prepared from (S)-3,3-dimethylbutan-2-amine and (S)-1-phenylpropylamine can be – as a function of the exocyclic side chain – either effective catalysts for the enantioselective epoxidation of unfunctionalized olefins or no catalysts at all. In the case of the (S)-1-phenylpropylamine derivative, an unwanted and unexpected Cope elimination derails the catalytic reactivity which can, however, be recovered by the addition of NBS prior to that of the substrate and other reagents.

Due to the constant demand for non-racemic molecules in both industrial and academic laboratories, many efforts have been devoted in the last 25 years to the development of enantioselective phase transfer catalyzed (PTC) processes. Much of this chemistry was recently reviewed – the latest reports were from 2003/2004 and treated essentially the synthesis of non racemic ?-amino acids. After a short historical introduction, this article will thus review enantioselective PTC reactions reported in the last three years (2003–2006) and demonstrate how broad and active the field is – and this considering ammonium-catalyzed reactions only.

The octahedral geometry of pentavalent hexacoordinated phosphorus allows the formation of chiral anions by complexation of the central phosphorus atom with three bidentate ligands. These simple-to-make derivatives can be combined with chiral cations and often display efficient NMR chiral shift, resolving and asymmetry-inducing properties. This paper is a short review of our research efforts directed towards the development of chiral anion mediated asymmetric chemistry.