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End date: 2019 × Start date: 2010 × Type: Text × Subject: chemistry × Subject: crystal structure ×

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    Enantio- and diastereoselective synthesis of γ-amino alcohols
    (Cambridge : Soc., 2015) Verkade, Jorge M. M.; Quaedflieg, Peter J. L. M.; Verzijl, Gerard K. M.; Lefort, Laurent; van Delft, Floris L.; de Vries, Johannes G.; Rutjes, Floris P. J. T.
    The γ-amino alcohol structural motif is often encountered in drugs and natural products. We developed two complementary catalytic diastereoselective methods for the synthesis of N-PMP-protected γ-amino alcohols from the corresponding ketones. The anti-products were obtained through Ir-catalyzed asymmetric transfer hydrogenation, the syn-products via Rh-catalyzed asymmetric hydrogenation.
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    A diuranium carbide cluster stabilized inside a C80 fullerene cage
    (London : Nature Publishing Group, 2018) Zhang, X.; Li, W.; Feng, L.; Chen, X.; Hansen, A.; Grimme, S.; Fortier, S.; Sergentu, D.-C.; Duignan, T.J.; Autschbach, J.; Wang, S.; Wang, Y.; Velkos, G.; Popov, A.A.; Aghdassi, N.; Duhm, S.; Li, X.; Li, J.; Echegoyen, L.; Schwarz, W.H.E.; Chen, N.
    Unsupported non-bridged uranium-carbon double bonds have long been sought after in actinide chemistry as fundamental synthetic targets in the study of actinide-ligand multiple bonding. Here we report that, utilizing I h(7)-C80 fullerenes as nanocontainers, a diuranium carbide cluster, U=C=U, has been encapsulated and stabilized in the form of UCU@I h(7)-C80. This endohedral fullerene was prepared utilizing the Krätschmer-Huffman arc discharge method, and was then co-crystallized with nickel(II) octaethylporphyrin (NiII-OEP) to produce UCU@I h(7)-C80·[NiII-OEP] as single crystals. X-ray diffraction analysis reveals a cage-stabilized, carbide-bridged, bent UCU cluster with unexpectedly short uranium-carbon distances (2.03 Å) indicative of covalent U=C double-bond character. The quantum-chemical results suggest that both U atoms in the UCU unit have formal oxidation state of +5. The structural features of UCU@I h(7)-C80 and the covalent nature of the U(f1)=C double bonds were further affirmed through various spectroscopic and theoretical analyses.
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    Crystal structure of (1S, 2R,4S)-1-((phenylamino)methyl)-4-(prop-1-en-2-yl) cyclohexane-1,2-diol), C16H23NO2
    (Heidelberg : Springer, 2011) Outouch, R.; Boualy, B.; El Firdoussi, L.; Ali, M.A.; Rizzoli, C.; Spannenberg, A.
    C16H23NO2, orthorhombic, P2 12121 (no. 19), a = 5.9637(3) Ã…, b = 8.8317(5) Ã…, c = 27.809(1) Ã…, V = 1464.7 Ã…3, Z = 4, Rgt(F) = 0.026, wRref(F2) = 0.040, T= 150 K.