Ruthenium phthalocyanine preparation

The use of metal phthalocyanine compounds has also been described (66,67). The catalysts can either be supported on an inert carrier or used in a liquid-liquid two-phase system. Various functionalized phthalocyanine ruthenium complexes have been mentioned for the reaction of interest. For instance, ruthenium phthalocyanine disulfonate transformed hept-3-ene into 3- -propylpentanol (80°C, 18 hours, 120 bar) in a two-phase system. Further details (67) on the preparation of metal complexes supported on silica- and alumina-type supports have appeared. Generally, a mixture of metal phthalocyanine sulfonate and hydrated alumina pro-... 

Phthalocyanine complexes within zeolites have also been prepared by the ship-in-a-bottle method (see Section 6.6), and have subsequently been investigated as selective oxidation catalysts, where their planar metal-N4 centres mimic the active sites of enzymes such as cytochrome P450, which is able to oxidize alkanes with molecular oxygen. Cobalt, iron and ruthenium phthalocyanines encapsulated within faujasitic zeolites are active for the oxidation of alkanes with oxygen sources such as iodosobenzene and hydroperoxides. Following a similar route, Balkus prepared Ru(II)-perchloro- and perfluorophthalocyanines inside zeolite X and used these composites for the selective catalytic oxidation of alkanes (tert-butylhydroperoxide). The introduction of fluorinated in place of non-fluorinated ligands increases the resistance of the complex to deactivation. 

The synthesis of ruthenium-metallated Pc derivatives using Ru3(CO)i2 in benzonitrile afforded ruthenium phthalocyanines either monocoordinated with CO or dicoordinated with benzonitrile. Cook and colleagues were the first to predict their utility in the preparation of further (pyridyl) ligated derivatives and showed that it was indeed straightforward. This chemistry is sufficiently robust and efficient to permit elaborate supramolecular complexes to be prepared, as demonstrated by the synthesis of porphyrin-phthalocyanine multichromophores 21 and 22, as illustrated in Figure 15. The absorption spectra of these arrays are essentially the sums of spectra of the starting materials. These observations indicate that there is little ground-state electronic interaction between the perpendicular maaocycles, in accordance with previous results published by Ng and Li (Section 4.1.1). ... 

Chemically modified electrodes have also been employed as detectors for CEEC [33,34]. Specifically, carbon paste modified with cobalt phthalocyanine was explored in our laboratories for selective detection of thiols [33]. Electrodes were produced by packing a 150 pm i.d. fused silica capillary with modified carbon paste to a depth of approximately 5 mm. This electrode was used for the selective detection of cysteine in urine. Later, ruthenium cyanide-modified electrodes were used for the simultaneous detection of thiols and disulfides at +850 mV (vs. Ag/AgCl) [34]. Modified carbon fiber microelectrodes were prepared by cycling the potential between 500 and 1000 mV at a scan rate of 50 cycles in an acidic deoxygenated plating solution containing RuClj, K RuiCN), and KCl. Detection limits for cystine were 3 pM. The selective detection of cystine in urine of a patient with kidney stones was demonstrated. 

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