Copper complexes hydrated

Then, as described in U.S. Patent 3,158,648, the optical isomers may be resolved as follows. 37 g of racemic a-methYl-3,4-dihYdroxYphenylalanine are slurried at 35°C in 100 cc of 1.0 N hydrochloric acid. The excess solids are filtered leaving a saturated solution containing 34.6 g of racemic amino acid of which about 61% is present as the hydrochloride. The solution Is then seeded at 35°C with 7 g of hydrated L-o -methYl-3,4-dihYdroxYphenYlalanine (6.2 g of anhydrous material). The mixture is then cooled to 20°C in 30 minutes and aged one hour at 20°C. The separated material Is isolated by filtration, washed twice with 10 cc of cold water and dried in vacuo. The yield of product is 14.1 g of L-a-methYl-3,4-di-hydroxyphenylalanine in the form of a sesquihydrate of 100% purity as determined by the rotation of the copper complex. 

Colon of copper complexes. When ammonia is added to 0.2 MCu2. the [Cu(NH3)4]2+ complex ion forms. The ammonia-containing ion is an intense deep blue, almost violet. The hydrated copper complex ion [Cu(H20)4]2+ is light blue. 

Jahn-Teller distortions cobalt and copper complexes, 2, 91 hydrates, 2, 308 Jahn-Teller effect, 5, 535 Jahn-Teller theorem, 1, 247 Jarosites... 

Subsequent reaction of porphyrazines 170 and 171 with Cu(OAc)2 resulted in the selective metalation within the macrocyclic cavity to provide the corresponding copper complexes 166 (62%) and 172 (47%). Treatment of pz 170 with manganese acetate and iron sulfate in dimethyl sulfate gave the dmso adducts 173 (70%) and 174 (85%), respectively (168). Axial ligation was also observed when other metals were incorporated such as cobalt acetate, nickel acetate, and zinc acetate to give the metal complexes 175 (83%), 176 (70%), and 177 (90%) as the hydrates. The axial ligand of... 

More advanced semiempirical molecular orbital methods have also been used in this respect in modeling, e.g., the structure of a diphosphonium extractant in the gas phase, and then the percentage extraction of zinc ion-pair complexes was correlated with the calculated energy of association of the ion pairs [29]. Semiempirical SCF calculations, used to study structure, conformational changes and hydration of hydroxyoximes as extractants of copper, appeared helpful in interpreting their interfacial activity and the rate of extraction [30]. Similar (PM3, ZINDO) methods were also used to model the structure of some commercial extractants (pyridine dicarboxylates, pyridyloctanoates, jS-diketones, hydroxyoximes), as well as the effects of their hydration and association with modifiers (alcohols, )S-diketones) on their thermodynamic and interfacial activity [31 33]. In addition, the structure of copper complexes with these extractants was calculated [32]. 

Jahn-Teller distortions cobalt and copper complexes, 91 hydrates, 308... 

Complexes of formazans having one or two carboxylic groups in the 2- or 2,2-positions of the aryl substituents, however, appear to be bicyclic. Thus, a hydrate was obtained on reaction of l,5-bis(2-carboxyphenyl)-3-cyanoformazan with copper acetate [76], The coordinated water could not be removed by drying and produced a broad band in the IR spectrum at 3450 cm-1. The copper complexes of formazans containing carboxyl groups were then assigned the structure 42. 

A large class of coordination compounds, metal chelates, is represented in relation to microwave treatment by a relatively small number of reported data, mainly p-diketonates. Thus, volatile copper) II) acetylacetonate was used for the preparation of copper thin films in Ar — H2 atmosphere at ambient temperature by microwave plasma-enhanced chemical vapor deposition (CVD) [735a]. The formed pure copper films with a resistance of 2 3 pS2 cm were deposited on Si substrates. It is noted that oxygen atoms were never detected in the deposited material since Cu — O intramolecular bonds are totally broken by microwave plasma-assisted decomposition of the copper complex. Another acetylacetonate, Zr(acac)4, was prepared from its hydrate Zr(acac)4 10H2O by microwave dehydration of the latter [726]. It is shown [704] that microwave treatment is an effective dehydration technique for various compounds and materials. Use of microwave irradiation in the synthesis of some transition metal phthalocyanines is reported in Sec. 5.1.1. Their relatives - porphyrins - were also obtained in this way [735b]. 

Preparation 3 illustrated the formation of a double salt, ammonium copper sulphate, (NH SCh-CuSCh-OI O. In the double salt, ammonium plays the part of a positive radical. In the present preparation ammonia plays an altogether different role. It does not possess a primary valence, and it enters into a molecular compound with the salt by virtue only of a secondary valence. In fact, the ammonia in this preparation is held in the same sort of a combination as the water in the hydrate CuS04-5H20. The molecules of ammonia would appear to be bound to the copper rather than to the sulphate radical, because when the salt is dissolved in water the four ammonia molecules remain in combination with the copper as the complex ion Cu(NH3)4++, while the sulphate radical appears as the ordinary SO4 ion. Thus we might say that this salt is the sulphate of the ammonio-copper complex. (Cf. Ammoniates, page 118.)... 

Cycloaddition Reactions. Bis(oxazoline) copper complexes such as 2 (and its hydrated congener) facilitate the [2 + 2] cycloaddition between silylketenes and glyoxylate/pyruvate esters (eq 18). The reaction is tolerant to various silyl substituents and structural variation on the dicarbonyl reactant. 

Faujasite-X zeolite (NaX) (Si/Al = 1.23, ca. 2 pm particle size, from Aldrich Chemical Company), ammonium hydroxide (assay 29+%, from Fisher Chemical Company), cobalt(II) chloride (99+ % assay) and copper nitrate hydrate [Cu(N03). H20, 101.7 % by EDTA complexation, from J.T. Baker Chemical Company] were used. 

If one heats the blue copper sulfate solution until the dry blue copper penta hydrate salt (CuS04 5 H20) remains, the complex is still in the ionic lattice, this time, the central ion with four H20 ligands and two O atoms from surrounding sulfate ions (see Fig. 9.2). The fifth I IzO is not attached to the cation, it is held between water molecules attached to cations and O atoms of sulfate ions [2] (see Fig. 9.3). Furthermore, if one heats the blue salt the crystals turn into a white substance H20 molecules leave the complexes and an ionic lattice remains with the arrangement of copper ions and sulfate ions. 

Incorporation of metal ions into porphyrins is affected by other compounds in solution. Lowe and Phillips (25) found that copper(II) ions were chelated with dimethyl protoporphyrin ester 20,000 times faster in 2.5% sodium dodecylsulfate (SDS) than in 5% cetyl trimethyl ammonium bromide (CATB). The increased activity of SDS treated porphyrin was attributed to electrostatic attraction between anionic micelles formed around the tetrapyrrole nucleus and the metal cation. The authors also reported the influence of certain chelating agents on the rate of copper complex formation. Equimolar concentrations of copper and 8-hydroxyquinoline or sodium diethylthiocarbamate in 2.5% SDS increased the reaction rate 38 and 165 times, respectively, above the control. Secondary chelators may act by removing the hydration sphere on the metal ion increasing its attraction to pyrrole nitrogens (26). 

Red-violet modification. A mixture of 2.05 g. (0.008 mol) of phenylbiguanide-p-sulfonic acid and 150 ml. of water is acidified with 1.5 ml. of concentrated hydrochloric acid (35%) and warmed to 60°. To this solution is added 1 g. (0.004 mol) of copper (II) sulfate 5-hydrate dissolved in 10 ml. of water. The resulting solution is then treated with dilute (12%) ammonia water drop by drop imtil the solution becomes just alkaline and the red-violet crystals of the copper complex separate. About 4 ml. of ammonia is required. The crystals are filtered, washed first with 100 ml. of water and finally with 15 ml. of ethanol, and dried in air. Yield 2.2 g. (93% based on copper taken). Anul. Calcd. for [Cu(H03SC6H4C2NsH5)2]-H20 N, 23.59 Cu, 10.71 H2O, 3.04. Found N, 23.66 Cu, 10.61, 10.64 H2O (loss at 90°), 3.0. 

Carbonic anhydrase (CA) is a zinc metalloenzyme involved in mammalian respiration, which catalyzes the hydration of carbon dioxide. Copper-complexed TPPC, competitively inhibits CA enzymatic activity as does copper-complexed TPPSj [32]. Experiments comparing the spectrophotometric characteristics of the two porphyrins in the presence of CA and apo-CA indicate that the zinc atoms in the active site of the enzyme are indeed involved in the interaction between the porphyrins and the enzyme. The metal-free porphyrins TPPSj and TPPC, do not inhibit the enzymatic activity of CA. Further, the spectrophotometric characteristics of these porphyrins in the presence of apo-CA were identical to those in the presence of wild-type CA, indicating the lack of involvement of the active site-coordinated zinc in the porphyrin-enzyme interaction for metal-free porphyrins. 

Oxygen nucleophiles The enantioselective addition of water to enones in an aqueous environment, catalysed by a copper complex with an achiral ligand, non-covalently bound to DNA has been reported to produce the corresponding )8-hydroxy ketones with <82% ee. Deuterium labelling demonstrated that the reaction is diastereospecific, with only the S yn-hydration product formed, for which outcome, there is no equivalent in conventional homogeneous catalysis ... 

Copper complexes containing abnormal imidazolylidene 4 were successfully applied to the [3+2] dipolar cycloaddition of azides and alkynes. " Related abnormal imidazolylidene gold(i) complexes showed good activity in the hydration of alkynes. However, the precursor complex required activation with a silver salt, which is likely to lead to carbene transfer (see Section... 

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