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A hypervalent silicon hydride with Si-H...K interactions was prepared and structurally characterized.

Abstract: In order to investigate the catalytic effect of TiN, TiMn2 and LaNi5 on the hydrogen storage capacity of LiAlH4, 2 mol% of the catalyst was milled with LiH/Al and then hydrogenated in Me2O. Doping with TiN, TiMn2 or LaNi5 led to substantial hydrogenation of LiH/Al in accordance with the formation of LiAlH4. In each case the amount of hydrogen absorbed was dependent on the catalyst and the ball-to-powder ratio used during milling. A high ball-to-powder ratio results in an improvement in the hydrogen storage capacity of LiAlH4. For each ball-to-powder ratio the highest hydrogen storage capacity was recorded for the TiN-catalyzed sample; hydrogen storage capacity increased from 3.2 to 4.8 to 6.0 wt.% H as the ball to-powder ratio increased from 10:1 to 20:1 to 40:1. The high levels of hydrogenation of LiH/Al catalyzed with TiN, TiMn2 and LaNi5 are remarkable because for the LiAlH4 system only a TiCl3 catalyst has previously been shown to result in rehydrogenation of the dehydrogenated products to LiAlH4. [Copyright &y& Elsevier]

Abstract: The microwave-assisted synthesis of [Os2Cl3(PEt2Ph)6]Cl, a useful intermediate in osmium chemistry, was performed in a minimum amount of time under aerobic conditions, and the product readily crystallized from the reaction solution. Its single crystal X-ray structure and a full characterization by NMR spectroscopy are reported for the first time. [Copyright &y& Elsevier]

Abstract: The structure of AlH3·2NMe3 has been investigated by single-crystal X-ray diffraction over the range of 296–173K. Over this temperature range a phase change is observed from Cmca to Pbcm where the methyl groups convert from a statistically disordered conformation to adopt a mutually eclipsed conformation at lower temperatures. Measurement of the unit cell dimensions shows a decrease in the lengths of the a and b axes, and an increase in that of the c axis as the temperature is lowered, with inflections apparent between 223 and 233K in the region of the phase change. Low-temperature DSC measurements reveal the change from Pbcm to Cmca to occur at 218.3K, with an enthalpy of 107.7Jmol−1. The molecular structure of AlH3·2NMe3 is compared with those of related amine adducts of Group 13 hydrides, either measured experimentally or calculated using DFT methods. 1H, 13C and 27Al NMR spectroscopy has also been utilized to characterize AlH3·2NMe3 and its 1:1 counterpart AlH3·NMe3. [Copyright &y& Elsevier]