Perchlorate-copper system

The identification of different carbonate binding modes in copper(II) and in zinc(II)/2,2 -bipyridine or tris(2-aminoethyl)amine/(bi)carbonate systems, specifically the characterization by X-ray diffraction techniques of both r)1 and r 2 isomers of [Cu(phen)2(HC03)]+ in their respective perchlorate salts, supports theories of the mechanism of action of carbonic anhydrase which invoke intramolecular proton transfer and thus participation by r)1 and by r 2 bicarbonate (55,318). 

However, aryl cyanides are more directly obtained by reaction of the arylthallium compound with various copper cyanides. Different reaction systems have been reported, such as CuCN or Cu(CN)2 in acetonitrile or pyridine with arylthallium acetate perchlorate monohydrates. Other systems involve the arylthallium bistrifluoroacetate with CuCN in acetonitrileor in DMF. With these systems, a number of aryl cyanides (114), heteroaryl cyanides (115) 25,126 indolyl cyanides (116) and (117)124 148 have been prepared. 

Finally, it should be said that the above-discussed osmotic pressure-forced retention of one of the components of a mixture subjected to separation according to size exclusion mechanism does not exclude the possibility of true retention-type solute/sorbent interactions. Hypercrosslinked polystyrene may well enter attractive interactions with soft and lipophilic (chaotropic [163]) anions, such as sulfide, thiosulfate, rhodanide, perchlorate, tetrafluoroborate, and hexafluorophosphate. Also, some cations such as silver, copper, and mercury may interact with the aromatic 71-systems of the polystyrene matrix, which will retard the movement of the ions. These interactions may contribute to the separation of the ions from their stiU larger competing ions, but they may also be counterproductive to the size exclusion effect and deteriorate the separation of the retarded ions from smaller species. 

We tried to accumulate oxidation reactions using copper chloride under these conditions (Fig. 6) but observed that the system had already started to deactivate after the first reaction. Furthermore, the system began to produce cyclohexanol in the accumulation reactions, which was not observed before. After 4 accumulations we obtained a 0.120 M solution of one + ol (8.3 1) with 100% selectivity but only 18% efficiency with respect to hydrogen peroxide. Using copper perchlorate in the absence of acetic acid, we were also able to accumulate one + ol to a concentration of 0.120 M (one ol = 5.9 1), but observed that the reaction was less efficient at the beginning (Fig. 7). Interestingly, the... 

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