A novel and convenient protocol for the catalytic hydrogen-deuterium exchange of biologically active tertiary amines utilizing the borrowing hydrogen methodology has been developed. In the presence of the readily available Shvo catalyst, excellent chemoselectivity toward α- and β-protons with respect to the nitrogen atom as well as high degree of deuterium incorporation and functional group tolerance is achieved. This allowed for the deuteration of complex pharmaceutically interesting substrates, including examples for actual marketed drug compounds. Notably, this method constitutes a powerful tool for the generation of valuable internal standard materials for LC-MS/MS analyses highly demanded for various life-science applications.

Peptide aldehydes 15a-c are protocol for the preparation and utilizaprepared without epimerization from tion of THF solutions of 11, the isolation enantiomerically pure (S)-a-amino acids of air-sensitive intermediates can be (Scheme 3). Reductive pinacol homocoupling of 15a-c, induced by vanadium complex 11 or niobium complex 16 in refluxing THF, yields C,-symmetrical (S,R,R,S)-configurated 6a, 6 b and 2, respectively, with moderate to high stereoselectivity (Scheme 4). In a novel

5along a coupled antiferromagnetic super-super-exchange via phosphate groups along c with ordering along b which likely is due to the contribution of dipole-dipole interactions. -(AVDEEV*, M.; LING, C. D.; TAN, T. T.; LI, S.; OYAMA, G.; YAMADA, A.; BARPANDA, P.; Inorg. Chem. 53 (2014) Structural and magnetic characterization of the site-ordered double perovskites are reported in order to show the effect of introducing Jahn-Teller active S = 1/2 Mo 5+ into the structure of Ba 2 MnMoO 6 which exhibits anomalous long-range antiferromagnetic order. The tetragonal distortion present in the Ba 2 NdMoO 6 end member persists to x  0.3 and is related to a tilting of the MO 6 octahedra. For x > 0.3, no deviation from the ideal cubic Fm3m symmetry is observed. Doping of Mn 2+ into the Nd 3+ site is associated with the oxidation of Mo 5+ to Mo 6+ . Curie-Weiss paramagnetic behavior above 150 K indicates negative Weiss constants from -24 to -85 K. This net antiferromagnetic interaction is weakest at x  0.5 where the disorder in cation site occupancy and competition with ferromagnetic interactions is at a maximum. The long-range antiferromagnetic order of the Ba 2 NdMoO 6 end member is strongly suppressed in the Nd/Mn Mo Chemical Thermodynamics, EquilibriaEquilibria E 4000 DOI: 10.1002/chin.201412007 Unexpected Stable Stoichiometries of Sodium Chlorides. -Cubic and orthorhombic NaCl 3 and two-dimensional metallic tetragonal Na 3 Cl are prepared in a laser--heated diamond anvil cell at 10 to 80 GPa in the Na-Cl system in the presence of excess chlorine and sodium. The samples are characterized by optical absorption spectroscopy, Raman confocal spectroscopy, synchrotron XRD, and DFT calculations. The calculated Na-Cl phase diagram features NaCl 3 (stable above 20 GPa), NaCl 7 (stable above 142 GPa), and Na 3 Cl 2 , Na 2 Cl, and Na 3 Cl, which are stable above 120, 100, and 77 GPa, respectively. -(ZHANG*, W.; OGANOV, A. R.; GONCHAROV, A. F.; ZHU, Q.; BOULFELFEL, S. E.; LYAKHOV, A. O.; STAVROU, E.; SOMAYAZULU, M.; PRAKAPENKA, V. B.; KONOPKOVA, Z.; Science (Washington, DC, U. S.) 342 (2013) (I) and Bi(IO 3 ) 3 (II) are hydrothermally synthesized from aqueous solutions of stoichiometric quantities of Bi(NO 3 ) 3 and I 2 O 5 (autoclave, 180 C, 24 h). The samples are characterized by powder XRD, SEM, UV/VIS diffuse reflectance spectroscopy, and DFT electronic structure calculations. (I) crystallizes in the orthorhombic space group Pca2 1 and (II) in the monoclinic space group P2/n. Both compounds show high photocatalytic activity for oxidative decomposition of methyl orange in aqueous solution. The photocatalytic efficiency of (I) is about 2.2 times higher than that of commercial TiO 2 . -(HUANG*, H.; HE, Y.; HE, R.; JIANG, X.; LIN, Z.; ZHANG, Y.; WANG, S.; Inorg. Chem. Commun. 40 (2014) (III) in nearly quantitative yield. The crystal structure of (IIb) is determined by single crystal XRD and those of (IIIb,c) (autoclave, 150 C, 24 h; 50, 60, 70, and 60% yield for the Na, K, Rb, and Cs compound, resp.). The samples ...

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A convenient procedure for the racemization of α-amino acid esters in the presence of catalytic amounts of salicylaldehydes is described. The combination of this racemization protocol with lipase-catalyzed ester hydrolysis allows successful dynamic kinetic resolution of various α-amino acid esters.