Crystal structure of trans-pyH[MoBr4py2] and reactivity of Trans-pyH[MBr4py2] (M = Mo, W; py = pyridine) towards nitrogen ligands and bromine Oxidation

Autor: Jurij V. Brenčič, R. Rotar, B. Čeh, Ivan Leban, Barbara Modec
Rok vydání: 1993
Předmět:
Zdroj: Zeitschrift f�r anorganische und allgemeine Chemie. 619:796-800
ISSN: 1521-3749
0044-2313
DOI: 10.1002/zaac.19936190427
Popis: The crystal structure of trans-pyH[MoBr4py2] has been determined: orthorhombic, Pnma (No. 62), a = 16.197(3), b = 13.995(3), c = 8.615(1) A, Z = 4, Dc = 2.23, Do = 2.20(3) g/cm3, V = 1 953(1) A3. R1, Rw = 0.057 and 0.053. Trans-[MoBr4py2]− anions with staggered conformation of pyridine rings are located on the mirror planes. MoBr, MoN(pyridine) distances are 2.593(1), 2.573(1), 2.227(8) and 2.213(7) A. Cations are located on the symmetry centers. The cation in trans-pyH[MBr4py2] can be replaced. Trans-NH4[MBr4py2] · H2O, Cs[MBr4py2], LH[MBr4py2] (M = Mo, W; L = 4-methylpyridine, 4-pic; 2,2′-bipyridyl, bipy) were prepared. The compounds of molybdenum and tungsten with the same chemical composition are isostructural. All compounds react with pyridine and 4-methylpyridine. The products are trans-MBr3L3, and in the case of molybdenum, also trans-MoBr3py2(4-pic). Bromine oxidizes trans-MI[MBr4py2] to trans-MBr4py2. Kristallstruktur von trans-pyH[MoBr4py2] und die Reaktivitat von trans-pyH[MBr4py2] (M = Mo, W; py = Pyridin) gegenuber Stickstoff-Liganden und zur Oxidation mit Brom. Die Kristallstruktur von trans-pyH[MoBr4py2] wurde bestimmt: orthorhombisch, Pnma (No. 62), a = 16,197(3), b = 13,995(3), c = 8,615(1) A, Z = 4, Dgemess. = 2,20(3), Drontg. = 2,23 g/cm3, V = 1953(1) A3. R1, Rw = 0,057 and 0,053. Trans-[MoBr4py2]−, mit der gestaffelten Konformation der Pyridin-Liganden in der Spiegelebene. MoBr- und MoN(Pyridin)-Abstande sind 2,593(1), 2,573(1), 2,227(8) und 2,213(7) A. Die Kationen befinden sich in den Symmetriezentren. Das Kation in trans-pyH[MBr4py2] ist ersetzbar; trans-NH4[MBr4py2] · H2O, Cs[MBr4py2], LH[MBr4py2] (M = Mo, W; L = 4-Methylpyridin, 4-pic; 2,2′-Bipyridyl, bipy) wurden dargestellt. Die Molybdan- und Wolfram-Verbindungen analoger Zusammensetzung sind isostrukturell. Alle Stoffe reagieren mit Pyridin und 4-Methyl-pyridin zu trans-MBr3L3 und im Fall des Molybdans auch zu trans-MoBr3py2(4-pic). Brom oxidiert trans-MI[MBr4py2] zu trans-MBr4py2.
Databáze: OpenAIRE
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