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The conjugate addition of carbon nucleophiles to acceptor activated olefins is one of the most important reactions for carbon-carbon bond formation. With optically active metal complexes this transformation can be catalyzed enantioselectively. This review is a collection of the newer literature (since 2001) on this topic. The metal salts and complexes applied are in a broad range, starting from solely Lewis acidic M(II) and M(III) compounds, such as magnesium, zinc, boron, aluminum and the lanthanoids. Transitionmetal catalysts suitable for asymmetric conjugate additions are compounds of ruthenium, iridium, nickel, and palladium. The most flourishing fields are, however, the catalysis with rhodium and copper complexes. Rhodium catalysts often have a chiral diphosphane like BINAP, or an optically active olefin as the ligand, the latter being a newer development. The privileged ligand structures for copper catalysts are monodentate phosphoramidites with axially chiral BINOL or other biphenol units.

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The efficient conversion of light into electricity or chemical fuels is a fundamental challenge. In artificial photosynthetic and photovoltaic devices, this conversion is generally thought to happen on ultrafast, femto-to-picosecond timescales and to involve an incoherent electron transfer process. In some biological systems, however, there is growing evidence that the coherent motion of electronic wavepackets is an essential primary step, raising questions about the role of quantum coherence in artificial devices. Here we investigate the primary charge-transfer process in a supramolecular triad, a prototypical artificial reaction centre. Combining high time-resolution femtosecond spectroscopy and time-dependent density functional theory, we provide compelling evidence that the driving mechanism of the photoinduced current generation cycle is a correlated wavelike motion of electrons and nuclei on a timescale of few tens of femtoseconds. We highlight the fundamental role of the interface between chromophore and charge acceptor in triggering the coherent wavelike electron-hole splitting.

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