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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Orthogonally N‐protected (Boc and Cbz) 4‐(1,2,3‐triazol‐4‐yl)‐substituted 3‐aminopiperidines are new scaffolds for combinatorial chemistry. They were prepared from a piperidine building block by a sequence of nucleophilic aziridine ring opening with NaN3 and subsequent copper‐catalyzedHuisgen 1,3‐dipolar cycloaddition with ten different alkynes. Constitution and relative configuration of the major as well as minor products were established by single‐crystal X‐ray structure analysis of bromophenylsulfonyl derivatives.

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The addition of diethylzinc to aromatic, heteroaromatic, and aliphatic aldehydes at room temperature is efficiently catalyzed by 1-7 mol% tetrabutylphosphonium chloride. The corresponding addition products are obtained in good to excellent yields of up to 99%. Moreover, polymer bond phosphonium salts can be used to catalyze this reaction with excellent recovery of the polymer bond catalyst up to three cycles. The application of chiral bifunctional phosphonium salts revealed a remarkable counter anion effect. Changing the anion, the activity of the tetrabutylphosphonium salt decreased in the order Cl -> Br -> I -≈ TsO -> BF 4 -≈ PF 6 -. However, the nature of the cation had also significant influence. Tetraalkylammonium chlorides showed similar activity compared to phosphonium chlorides, while alkaline metal chlorides proved to be considerably less active.