Metalorganic complexes

IR spectroscopy has proved that SILP catalysts have metalorganic complexes dissolved in the liquid layer, which then worked as a homogeneous catalyst Riisager et al. [12] have made spectroscopic measurements of a rhodirun-sulfoxantphos complex which was immobilized in an SILP system. This SILP catalyst was tested in the continuous-flow fixed-bed hydroformylation of propene. Spectroscopy of the SILP system was performed in situ under conditions closely related to the reaction conditions, that is, imder various gas atmospheres and at 100 °C. The result was that the Rh-sulfoxantphos complex of the SILP catalyst behaved similar to an analogous rhodium-xanthene catalyst dissolved in the homogeneous phase. Analysis of the CO stretching band showed that the catalyst was in equilibrium between a dimeric form and two monomeric forms (Scheme 8.3) and, consequently, that the hydroformylation reactions were indeed homogeneously catalyzed. 

Contrary to the hydroformylation or carbonylation of olefins, in the carbonylation of acetylenes addition of the carboxyl group occurs, without exception, to one of the C-atoms of the triple bond. Generally, isomerization of the unsaturated bond via intermediate metalorganic complexes or isomerization of the carbon skeleton are not observed. 

As mentioned above, the number of calixarene and calix-type compounds structures investigated and deposited so far in CSD is very big it is not possible to discuss all of them in this chapter. So the discussion will be limited mostly to organic inclusion compounds and co-crystals of course having in mind that the monomolecular crystal structures as well as the metalorganic complexes are also a rich source of valuable information about geometries, possible conformations, coordinatiOTi types, intermolecular interactions, etc. 

R3Si709(0H)3], with group 13 metalorganics MR3 have been investigated in detail. In particular, reactions of alanes RxA1H3 x (x= 1-3) have been studied,624 yielding novel heterocyclic and cluster-type complexes. 

Practical importance is also attached to the electrolysis of complex metalorganic substances on the lead anode. E.g., Ziegler suggested an industrial technique for the production of lead tetraalkyl derivatives through readily accessible complex aluminum compounds. 

A brand-new methodology for synthesizing glycals from noncarbohydrate precursors, one based on cyclization of acetylenic alcohols, has emerged from the field of metalorganics. Molybdenum pentacarbonyl-trialkylamine complexes have been found to efficiently catalyze cyclization of l-alkyn-4-ols to substituted dihydrofurans [233,234]. This same transformation has been successfully carried out on asymmetrically substituted alcohols the furanoid glycals 132, 134, and 135 (O Scheme 45) so obtained have in turn been used as intermediates in the synthesis of nucleosides [235]. 

Eq. 117. Since breaking this C—C bond requires more energy, it is not necessarily so that the most energetically favoured TMM-Pd species act as intermediate, TMM-Pd-complexes with a higher energy level may be reasonable intermediates if they react immediately with a second olefin. We believe that in the cycloaddition reaction with methylenecyclopropane the first metalorganic intermediate is a complex in which both olefins are coordinated to the metal and so held in proximity to each other. Further reaction may involve a direct or a stepwise coupling as shown in Eq. 118. It is unknown at the present time which process occurs and whether it also depends on the nature of the metal and of the second olefin. 

Y. Akiyama, T. Sato and N. Imaishi, Reaction Analysis for Z1O2 and Y2O3 Thin-Film Growth by Low-Pressure Metalorganic Chemical-Vapor-Deposition Using Beta-Diketonate Complexes, J. Cryst. Growth, 147, 130-146(1995). 

To satisfy the bond-stabilization concept, it appears essential to reclassify the inorganic azides. Hence, five classes are identified here and are listed in Figure 1 as normal azides, mixed azides, hetero azides, azido complexes, and metalorganic azides. 

Kawai, H., S. Imanaga, K. Kaneko, and N. Watanabe. 1987. Complex refractive indices of AlGaAs at high temperature measured by in situ reflectometry during growth by metalorganic chemical vapor deposition. Journal of Applied Physics 61 328-332. 

Pope, M. T. Muller, A. (Eds.), (1994). Polyoxometalates From Platonic Solids to Anti-Retroviral Activity, Kluwer Academic Publishers, Dordrecht, The Netherlands Reinoso, S. Vitoria, P. Felices, L. S. Lezama, L. Guti6rrez-Zorrilla, J. M. (2006). Analysis of Weak Interactions in the Crystal Packing of Inorganic Metalorganic Hybrids Based on Keggin Polyoxometalates and Dinuclear Copper(II)-Acetate Complexes. Inorg. Chem., Vol.45, pp. 108-118... 

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