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91.
The reaction of enol acetates with alcohols in the presence of a catalytic amount of a rhenium complex, such as ReBr(CO)5, produced the corresponding ketones and aldehydes in moderate to good yields. It was suggested that the preparation of an ether, an intermolecular dehydrated product, was the first step of the reaction. 相似文献
92.
93.
Rhenium oxide nanoparticles have been prepared using ultrasonication at 20 kHz. Samples characterization was committed via SEM-EDX, TEM, XRD, and Raman spectroscopy. Various experimental parameters were examined, including precursor/substrate amounts, ultrasonication intensity, and type of solvent used. Insights to the agglomeration of the prepared nanoparticles depending on the preparation parameters are given. As ultrasonic source we used either an ultrasonic probe by Sonics & Materials Inc. (20 kHz, 750 W net output) or a Bandelin SONOPULS HD 3200 ultrasound generator (20 kHz, 200 W net output) at intensities between 30 and 100 W/cm2. The rhenium oxide nanoparticles haven been decorated on state-of-the-art anode materials (NiO/GDC) for solid oxide fuel cells (SOFCs) in order to prepare catalytically more active anode powders. These experiments revealed that ultrasonication intensity and solvents used are able to affect final nanoparticles size distribution and morphology. At the same time, ratio of precursor and substrate compounds amounts as well as ultrasonication intensity and duration were all found to affect the decoration loading extend of nanoformations on substrate powders. The results showing the influence of the above-mentioned parameters allowed for the quantification of the effects on the loading and the preferable sites of the decoration. 相似文献
94.
95.
A novel copper molybdate with mixed ligands, [{(Cu·phen)2(tp)}{(Cu·phen·H2O)2(tp)}{Mo4O14}] (phen=1,10-phenanthroline, tp=terephthalate) 1, has been hydrothermally synthesized and structurally characterized. The crystal belongs to monoclinic system, space group P21/c with a=13.1711(7), b=19.6132(10), c=13.6910(7) (A), β=117.6870(10)°, V=3131.8(3)(A)3, Z=2, C64H44Cu4Mo4N8O24, Mr=1946.99, Dc=2.065 g/cm3, F(000)=1920, μ(MoKα) (A) 2.198 mm-1, R=0.0810 and wR=0.2012 for 4233 observed reflections (Ⅰ > 2σ(Ⅰ)). The structural analysis indicates that the title compound contains a discrete tetramolybdate cluster decorated with copper complex fragments and tp ligands bridging the clusters into a wave-like layer. The hydrogen bonding between adjacent layers further extends the compound into a 3-D framework. 相似文献
96.
97.
合成了12种稀土金属硫氰酸盐与N-对氯苯基氮杂15-冠-5的固体配合物,进行了元素分析和电导、红外光谱、电子光谱测定及热重-差热分析,并对Sm(SCN)3·L作了X射线单晶结构分析,结果表明:Sm(Ⅲ)离子与冠醚上的5个杂原子及3个硫氰酸根上的氮原子配位,配位数为8. 相似文献
98.
Maria S. Tarasenko Nikolay G. Naumov Dmitry Yu. Naumov Sung-Jin Kim Vladimir E. Fedorov 《Polyhedron》2008
A series of new compounds containing rare earth cations (Eu to Yb) and paramagnetic cluster anion [Re6Te8(CN)6]3− was prepared and investigated. The X-ray structural analyses have revealed that the compounds [{Ln(H2O)4}{Re6Te8(CN)6}] · 2.5H2O; Ln = Eu (1), Tb (3), Dy (4), Ho (5), Er (6), Tm (7), [{Gd(H2O)3}{Re6Te8(CN)6}] · 2.5H2O (2) and [{Yb(H2O)4}{Re6Te8(CN)6}] (8) are three-dimensional polymers based on Re–CN–Ln interactions. Measurements of magnetic susceptibility for 2 and 5 showed that effective magnetic moment (at 300 K) was 8.13 μB for compound 2 and 10.79 μB for compound 5 with weak antiferromagnetic ordering appeared at low temperatures. 相似文献
99.
Hailin Dong 《Journal of organometallic chemistry》2011,696(9):1803-7127
[ReBr2(NO)(CH3CN)(PTA)2] (PTA = 1, 3, 5-triaza-7-phosphaadamantane) catalyzes the alcoholysis of ammonia-borane and amine-boranes and the catalytic transfer hydrogenations of various terminal olefins. Excellent yields were achieved at 70 °C in isopropanol using tBuOK as a co-catalyst affording TOF values up to 396 h−1. 相似文献
100.
Andrea I. Licht 《Journal of organometallic chemistry》2003,687(1):142-152
The reaction of ω-alkenyl substituted zirconocene dichloride complexes with two equivalents of n-butyllithium is strongly influenced in the presence of alkenes and alkynes. Metallacyclic zirconocene complexes of novel structures are obtained. The additives alkenes and alkynes compete with the ω-alkenyl substituents and the intermediate 1-butene for the formation of a metallacyclic structure. The reaction of ω-alkenyl substituted zirconocene dichloride complexes with two equivalents of ethyllithium and n-hexyllithium gives analogous reactions and metallacycles as with n-butyllithium. 相似文献