Copper chloride complexes with complex preparation

Copper ethylene chemistry is well developed, but reports of polymerizations based upon copper are rare. The amidinate ligand, A/,A/ -ditrimethylsilyl-benzamidinato, has been reported to support copper-catalyzed ethylene polymerizations. It is prepared from hexamethyldisilazane, benzonitrile, and tri-methylsilyl chloride. The resulting copper chloride complex, 2, when activated with methyl-aluminoxane, produced polyethylene with Mv = 820 000 and = 138 In another patent. 

The tri- or tetraamine complex of copper(I), prepared by reduction of the copper(II) tetraamine complex with copper metal, is quite stable ia the absence of air. If the solution is acidified with a noncomplexiag acid, the formation of copper metal, and copper(II) ion, is immediate. If hydrochloric acid is used for the neutralization of the ammonia, the iasoluble cuprous chloride [7758-89-6], CuCl, is precipitated initially, followed by formation of the soluble ions [CuClj, [CuCl, and [CuCl as acid is iacreased ia the system. 

CHROMIUM TRIOXIDE-PYRIDINE COMPLEX, preparation in situ, 55, 84 Chrysene, 58,15, 16 fzans-Cinnamaldehyde, 57, 85 Cinnamaldehyde dimethylacetal, 57, 84 Cinnamyl alcohol, 56,105 58, 9 2-Cinnamylthio-2-thiazoline, 56, 82 Citric acid, 58,43 Citronellal, 58, 107, 112 Cleavage of methyl ethers with iodotri-methylsilane, 59, 35 Cobalt(II) acetylacetonate, 57, 13 Conjugate addition of aryl aldehydes, 59, 53 Copper (I) bromide, 58, 52, 54, 56 59,123 COPPER CATALYZED ARYLATION OF /3-DlCARBONYL COMPOUNDS, 58, 52 Copper (I) chloride, 57, 34 Copper (II) chloride, 56, 10 Copper(I) iodide, 55, 105, 123, 124 Copper(I) oxide, 59, 206 Copper(ll) oxide, 56, 10 Copper salts of carboxylic acids, 59, 127 Copper(l) thiophenoxide, 55, 123 59, 210 Copper(l) trifluoromethanesulfonate, 59, 202... 

Copper(II) complexes of 2,6-lutidylphenylketone thiosemicarbazone, 38, have been prepared from copper(II) chloride and copper(II) bromide [186]. Similar to 2-pyridyl thiosemicarbazones, 38-H coordinates via the ring nitrogen, the azomethine nitrogen and the thiol sulfur based on infrared spectral assignments. Magnetic susceptibilities and electron spin resonance spectra indicate dimeric complexes and both are formulated as [Cu(38-H)A]2 with bridging sulfur atoms. The electronic spectra of both halide complexes show band maxima at 14500-14200 cm with shoulders at 12100 cm S which is consistent with a square pyramidal stereochemistry for a dimeric copper(II) center. 

A bottle of cuprous chloride solution prepared by standing cupric chloride in strong hydrochloric acid over excess copper burst on standing. In the presence of some complexing agents, copper can react with aqueous media to form hydrogen. Slow pressurisation by this means explains the above explosion (Editor s comments). The metal is also known to dissolve in cyanides and some amine solutions. 

To better elucidate the most critical impurities, a sample of the precipitated solid copper(II) complex formed by treating raw NaNT solution with copper(II) chloride was prepared for LC-MS analysis. As the unwanted impurities most likely precipitated following the addition of Cu11, this solid was an ap-... 

The basic study was performed on copper complexes with N,N,N, N1-tetramethylethane-1,2-diamine (TMED), which were known to be very effective oxidative coupling catalysts (7,12). From our first kinetic studies it appeared that binuclear copper complexes are the active species as in some copper-containing enzymes. By applying the very strongly chelating TMED we were able to isolate crystals of the catalyst and to determine its structure by X-ray diffraction (13). Figure 1 shows this structure for the TMED complex of basic copper chloride Cu(0H)Cl prepared from CuCl by oxidation in moist pyridine. 

Poly(2,6-dimethylphenylene ether) can be prepared by dehydrogenation of 2,6-dimethylphenol with oxygen in the presence of copper(l) chloride/pyridine as catalyst at room temperature. It is known that the mechanism involves a stepwise reaction, probably proceeding via a copper phenolate complex that is then dehydrogenated. 

The reaction of imidazole-4,5-dicarbaldehyde with 2-aminoethylpyridine in the presence of copper(II) chloride has enabled the preparation of a binuclear complex (equation 2).29 A more common class of binuclear complex is based on template reactions of a phenolic dialdehyde with various amines and includes the copper complexes (14)30 31 and (15).32 Reactions of this type can be extended to the synthesis of macrocyclic binuclear complexes such as (16).33,34... 

The reaction of phenylhydrazine with copper(II) chloride in aqueous solution gives [Cu4Cl4(PhNNH)] (13) and the reactions of 1,2-disubsti-tuted hydrazines with copper(II) salts give complexes such as [Cu2-Cl2(MeNNMe)l (46, 142). The reaction of substituted hydrazines (or lithiated, substituted hydrazines) with halido complexes of the transition metals can yield diazene complexes. Complexes of Ni, Pd, Pt (147, 199,213), and Rh (209) have been prepared in this manner [Eq. (25)]. 

The copper(n) chloride complex of 2-(2 -quinolyl)methylene-3-quinuclidinone has i.r. and electronic spectra consistent with the presence of a very distorted tetrahedral environment about the copper.120 Copper(n) complexes of the 2,3-dipyridylquinox-aline (10),89 5-aminopyrazoles,98 pyrazine and various substituted pyrimidines,636 and several substituted 3-methylpyrazoles678 have been reported. Two different forms of Cu(py)2(CNS)2 can be obtained depending upon the method of preparation 79... 

The process of ethylchlorosilane preparation by copper-catalysed ethyl-chloride reaction with silicon is very complex, and the mechanism of this process has not been fully established. However, similarly to the synthesis of methylchlorosilanes, the direct synthesis of ethylchlorosilanes most... 

The copper(II) chloride and cobalt(II) chloride complexes of 199 were prepared elemental analyses indicate that in both cases there are two metal associated with each cryptand. To date, however, no crystals suitable for X-ray structural determination studies have been obtained 149). 

Cu(l) and Fe(ll) complexes prepared in situ by reacting copper(l) or iron(ll) chloride with 1 equiv of ligand LI (tris(pyridin-2-ylmethyl)amine) or L2 are efficient catalysts for atom-transfer radical addition reactions. For instance, pent-4-enyl trichloroacetate was converted into 3,3,5-trichlorooxocan-2-one in 90% and 99% yield, respectively, when CuCl-Ll and CuCl-L2 were used as catalysts (Scheme 30) <2000J(P1)575>. 

Polymeric complexes are formed when copper(I) chloride reacts with dialkylhydrazines (105) or with 3,5,5-trimethylpyrazolidine. In Cu2Cl2(MeN=NMe) the structure consists of parallel Cl-Cu-Cl chains cross-linked by weak Cu-Cl bonds and strong Cu-N a bonds (47). Structures of CuI(PhN=NH) and Cu4Cl4(PhN=NH) may be similar (282, 290). Diazoaminobenzene copper(I) (110, 245) can be prepared from copper and the ligand it is dimeric with each copper linearly coordinated to 1,1 iV or 3,3 N atoms (48). The cation in [Cu(PhN2Ph)]-CIO4 may have a related structure (265). 

Bipyridyl and phenanthroline give polymeric 1 1 complexes with eopper(II) chloride 597). The existence of the dimeric ion [(bipy)Cu(OH)2Cu(bipy)] + in solution has been established 177, 566) and it has been isolated as the lilac perchlorate (498). The species (bipy)Cu + has surprisingly large affinity for ligands other than OH (370). The di-/a-hydroxo cation considered above has now been prepared with a variety of counter ions the corresponding phenanthroline salts are also known. There is no evidence of antiferromagnetic interaction between the copper(II) ions even at 80°K (321). When the counter ion is iodide or thiocyanate there is evidence for metal ion-coimter ion interaction. 

An example of complexation of Ji bonds is illustrated in the isomerization reaction shown in Sch. 39. Use of copper chloride enables the efficient conversion of the cis olefin 168 to the trans olefin 169 [77]. (CuOTf)2(C6Hg) can be readily prepared (or purchased) and has been used for [2 + 2] photocycloaddition. An example of norbor-nene dimerization is shown below in which the Cu(I) forms a n complex with two molecules of the olefin and enables a facile cycloaddition.[51]... 

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