Complex the catalytically active

The second example demonstrated immobilization via ship in a bottle , ionic, metal center, and covalent bonding approaches of the metal-salen complexes. Zeolites X and Y were highly dealuminated by a succession of different dealumi-nation methods, generating mesopores completely surrounded by micropores. This method made it possible to form cavities suitable to accommodate bulky metal complexes. The catalytic activity of transition metal complexes entrapped in these new materials (e.g, Mn-S, V-S, Co-S, Co-Sl) was investigated in stereoselective epoxidation of (-)-a-pinene using 02/pivalic aldehyde as the oxidant. The results obtained with the entrapped organometallic complex were comparable with those of the homogeneous complex. 

Hence, there are strong grounds to state that compounds with the tetra-nuclear cluster magnesium core formed in Mg-RH films have catalytic properties similar to those of transition metal complexes. The catalytic activity of organomagnesium clusters can be very high. 

We have demonstrated the ACP reaction catalyzed by Ru Pybox complexes. The catalytic activity of ruthenium complexes is commonly not strong. Nevertheless, ruthenium catalysts activated by newly designed ligands have recently received much attention not only for ACP but also for the nonasymmetric version in terms of coordination chemistry and also industrial curiosity because of high stereoselectivity. We believe that further improvement of the ruthenium catalysts will be in environmental interest to realize industrially applicable process. 

The metal complexes most often studied as polymer-bound catalysts have been Rh(I) complexes, such as analogues of Wilkinson s complex. The catalytic activity of a bound metal complex is nearly the same as that of the soluble analogue. Rhodium complexes are active for alkene hydrogenation, alkene hydroformylation, and, in the presence of CH3I cocatalyst, methanol carbonylation, etc. Polymer supports thus allow the chemistry of homogeneous catalysis to take place with the benefits of an insoluble, easily separated catalyst . ... 

Compared to the Mn complexes, the catalytic activity of Cu-aza macrocycles has not been explored much. Among the different Cu tri-and tetra-aza complexes investigated [53], Cu(tacn)Y, Cu(Me4Cyclen)Y, and Cu(cyclam)Y show high TOF of around 50-70 h 1 at 55°C in the oxidation of ethylbenzene with tBuOOH. With CuY mainly benzaldehyde is formed, pointing to the importance of radical pathways. In homogeneous R conditions side-chain alkylations as well as ring hydroxylation occur. 

The catalytic activity of polymer-metal complexes has been determined from the value of the initial rate of substrate oxidation. For polyampholyte-copper (II) complexes the catalytic activity decreases in the sequence 1 VI-AA>St-DMAPMAMA> MEAVEHC-M A A > 2M5 VP-AA. 

Polymer and silica gel supports have been used to tiy to prevent fwmatitm of dimeric organometallic complexes. The catalytic activities of many bound complexes have been tested, and in some cases the major species in die support have been identified spectroscopically. However, the structure observed spectroscopically is not necessarily that of the active catalyst... 

The chloro(methyl) complexes [(K -P,N)-Ph2PCH2CH2NR2]Pt(Cl)Me are even more active as catalysts than the dimethyl complexes. The catalytic activity increases in the series R = Me < Et < Pr, i.e. parallel to the weakening of the Pt-N interaction. The reaction was tested for the reaction of allyl chloride, PhsCCl, CHCI3,1,1,2,2-tetrachloroethane or H2CCI2 with PhMc2SiH the reactivity of the chlorides decreased in the given order. 

The use of the binaphthyl-based chiral polymers in catalysis has been explored. We have demonstrated that incorporation of aluminum metal centers into the rigid binaphthyl polymer backbones leads to greatly enhanced catalytic activity over the monomeric aluminum complex. The catalytic activity of the polymeric aluminum and titanium complexes in the Mukaiyam aldol reaction has been studied. These polymeric metal complexes represent a new generation of polymer-based catalysts... 

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