Alkyl acetates by stoichiometric reaction of alcohols with the methylene bridged complex [Fe2(μ-CH2)(CO)8]

Reactions of Roussin's red salt in THF with monofunctional electrophiles have given products of type (μ-RS)₂Fe₂(NO)₄, with R = CH₃, C₂H₅, CH₂CHCH₂, PhCH₂, Me₃Sn, Ph₃Sn, Ph₃Pb, PhHg and ν⁵-C₅H₅Fe(CO)₂, all of which are more or less air-sensitive, especially in solution. Similar reactionsattempted with difunctional electrophiles, Ln_nMX₂, were unsuccessful except in the case of (Ph₃P)₂PtCl₂ which gave monomeric product, (Ph₃P)₂PtS₂Fe₂(NO)₄ of as yet unknown structure. A comparison is made between the reactivity of [(μ-S)₂Fe₂(NO)₄]^2? and [(μ-S)₂Fe₂(CO)₆]^2?.     

2-phosphanylphenolate nickel catalysts for the polymerization of ethylene

The previously unknown methallylnickel 2-diorganophosphanylphenolates (R=Ph, cHex) were synthesized and found to catalyze the polymerization of ethylene. To explore the potential for ligand-tuning, a variety of P-alkyl- and P-phenyl-2-phosphanylphenols was synthesized and allowed to react with [Ni(cod)(2)] (cod=1,5-cyclooctadiene) or with NiBr(2).DME and NaH. The complexes formed in situ with [Ni(cod)(2)] are generally active as ethylene polymerization catalysts with all the ligands tested, whereas the latter systems are inactive when 2-dialkylphosphanylphenols are applied. M(w) values, ranging from about 1000 to about 100000 g mol(-1), increase for various R(2)P groups in the order R=Ph相似文献   

Decomposition of thin titanium deuteride films; thermal desorption kinetics studies combined with microstructure analysis

The thermal evolution of deuterium from thin titanium films, prepared under UHV conditions and deuterated in situ at room temperature, has been studied by means of thermal desorption mass spectrometry (TDMS) and a combination of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The observed Ti film thickness dependent morphology was found to play a crucial role in the titanium deuteride (TiD_y) film formation and its decomposition at elevated temperatures. TDMS heating induced decomposition of fine-grained thin Ti films, of 10-20 nm thickness, proceeds at low temperature (maximum peak temperature T_m about 500 K) and its kinetics is dominated by a low energy desorption (E_D = 0.61 eV) of deuterium from surface and subsurface areas of the Ti film. The origin of this process is discussed as an intermediate decomposition state towards recombinative desorption of molecular deuterium. The TiD_y bulk phase decomposition becomes dominant in the kinetics of deuterium evolution from thicker TiD_y films. The dominant TDMS peak at approx. T_m = 670 K, attributed to this process, is characterized by E_D = 1.49 eV.     

Selective Hydrovinylation of Styrene in a Membrane Reactor: Use of Carbosilane Dendrimers with Hemilabile P,O Ligands

A codimerization of styrene and ethene can be carried out continuously in a nanofiltration membrane reactor with dendritic Pd complexes such as 1 . The selectivity of the reaction is increased considerably under continuous conditions. The activity and selectivity of monomeric model complexes and the dendritic catalysts were compared in batch reactions.