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Detailed identification and monitoring of gaseous species released during thermal decomposition of two thiourea (tu) complexes of CuCl, one of them, Cu(tu)Cl 1/2H2O (1) poor, while the other, Cu(tu)3Cl (2) rich in thiourea, have been carried out in flowing air atmosphere up to 800 °C by both coupled TG-EGA-FTIR and simultaneous TG/DTA-EGA-MS. The thermal decomposition of 1, prepared actually from CuCl, has shown evolution of similar gas mixture and dynamics by TG/DTA-MS, as had been measured with TG-FTIR and published earlier, except that no evolution of ammonia has been detected, at all. Probably, the intense co-evolution of acidic vapors (HCl and SO2) has prevented NH3 to reach the ionization chamber of the mass spectrometer. While in case of anhydrous 2, Cu(tu)3Cl rich in thiourea, between 180 and 240 °C, the main gaseous decomposition products are ammonia (NH3), carbon disulfide (CS2), and isothiocyanic acid (HNCS). At about 250 °C, gas-phase exothermic oxidation of CS2 and HNCS vapors occurs, resulting in a sudden release of sulfur dioxide (SO2), carbonyl sulfide (COS), and hydrogen cyanide (HCN). Also a definite evolution of cyanamide (H2NCN) is observed just above 250 °C. Between 350 and 500 °C, a more intense oxidation process of both organic condensed residues and copper(I) sulfides into copper(II)-oxo-sulfates appears, which is also indicated by intense evolution of CO2, SO2, and H2NCN (and/or HNCO). Above 700 °C, the oxo-sulfates start to decompose resulting in repeated evolution of SO2. All species identified by FTIR gas cell have been also confirmed by mass spectrometry. Evolution of HCl from Cu(tu)3Cl (2) has been detected by either of the two EGA methods.

The ability of copper(I) chloride to catalyze the ring-opening isomerization of alkyl-, phenyl-, vinyl-, and cyclopropyl-substituted gem-chlorofluorocyclopropanes to chlorofluoroalkenes or chlorofluoroalkadienes was found.

Direct transformation of five-membered zirconacycles to carbocyclic compounds is of great synthetic interest. The reaction of zirconacycles with electrophiles containing at least two reactive functional groups or an oxidant affords various carbocycles through cross coupling, addition, and/or oxidative coupling reactions. In this paper, we present our recent results on the zirconacycle-mediated formation of carbocycles, including: (1) 1,1-cycloaddition of oxalyl dichloride with zirconacycles; (2) benzoquinone-promoted coupling of zirconacyclopentadienes in the presence of CuCl; (3) cycloaddition of zirconacyclopentadienes to quinones; (4) cycloaddition of zirconacyclopentadiene with 2-bromoacrylate, 2-bromoacrylaldehyde and 3-bromofuran-2,5-dione in the presence of CuCl; (5) one-pot coupling of two alkynes and an alkene to form cyclohexene derivatives via zirconacyclopentadienes; and (6) dianionic cycloaddition of decatetraenes with esters or acyl chlorides to form nine-membered carbocycles.

(1,3-Bis(2,4,6-trimethylphenyl)imidazol-2-ylidene)copper(I) chloride (1) was prepared by the reaction of 1,3-bis(2,4,6-trimethylphenyl)imidazolium chloride and copper(I) oxide in refluxing tetrahydrofuran. In contrast to previously published methods of preparation of N-heterocyclic carbene complexes of copper(I) halides, this synthesis requires neither an inert atmosphere nor scrupulously dry solvents. The structure of 1 was determined by elemental analysis, 1H and 13C NMR, and a single-crystal X-ray diffraction study. The X-ray crystal data reveal linear coordination about the copper(I) center and linear chains of molecules formed with intermolecular head-to-tail C–H···Cl interactions.

Single crystals of the organometallic material tetra(thiourea)copper(I) chloride (TTCC) were grown from aqueous solution. It is interesting to observe that Co2+-doping influences the efficiency of some of the physical properties of TTCC. Presence of Co2+ ions in the doped specimen is confirmed by energy dispersive X-ray spectroscopy (EDS) and chemical tests. FTIR studies reveal that the binding of thiourea with copper chloride occurs through sulphur. Doping results in reduction in the intensity of XRD peaks. SEMreveals that doping results in layered growth of the crystal. DSC confirms slight variations in the decomposition pattern. Mechanical stability of the doped specimen is much better than TTCC. Optical transparency is slightly enhanced by doping and a wide transmission in the visible region is observed. TTCC is non-linear optics (NLO) inactive and the second harmonic generation (SHG) efficiency is not influenced much by the added dopant.

The synthesis of a heteroligand complex of CuCl with triphenylphosphine and 5-pyridine-4-yl-5,6-dihydro-[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione (L) of composition { [CuCl(PPh3)(L)](CH3 CN)}2 (I) is described. The crystals of complex I are triclinic: space group \(P\bar 1\), a = 8.928(2) A, b = 13.872(3) A, c = 14.470(3) A, α = 72.89(3)°, β = 88.41(3)°, γ = 77.02(3)°, and Z = 2. The Cu(1) atom has a quasi-tetrahedral environment including the phosphorus atom of the triphenylphosphine molecule, nitrogen atom of the pyridyl radical of molecule L, and two bridging chloride ions. The fact that noncoordinated sulfur atoms are present can be used for the further interaction of complex I with soft Lewis acids.

The reactivity of chlorohydrocarbons with different electron affinities (Ae) and C-Cl bond dissociation energies (EC-Cl) in the oxidation of copper(I) chloride complexes was studied. The rate of oxidation depends only on Ae. Chain initiation, involving Cu(I), occurs by an electron-transfer mechanism.

Crystals of the π-complex [C4H8N2(C3H5)4]2+[CuCl2]–2 (I) were prepared by ac electrochemical synthesis from copper and N,N,N′,N′-tetraallylpiperasinium chlorides in alcohol solution. Similar synthesis with the use of the metal and N,N,N′,N′-tetraallylpiperasinium bromides yielded the complex [C4H8N2(C3H5)4]2+[CuBr3]2– (II). Structures I and II were studied by X-ray diffraction (DARCh automated single-crystal diffractometer, MoKα radiation). Crystals of I are triclinic, space group P1¯, a = 8.650(3) A, b = 7.572(2) A, c = 8.095(3) A, α = 100.45(2)°, β = 83.91(2)°,γ = 99.89(2)°, V = 512.1(6) A3, Z = 1. Crystals of II are orthorhombic, space group Pn21a, a = 17.673(3) A, b = 14.369(6) A, c = 8.244(2) A, V = 2093(2) A3, Z = 4. In structure I, the potentially tetradentate N,N,N′,N′-tetraallylpiperasinium cation uses two centrosymmetric allyl groups for bonding with copper atoms, whose environment is completed to the trigonal-planar coordination with the chlorine atoms. The [C4H8N2(C3H5)4]2+[CuCl2]–2 groups are joined into a three-dimensional framework by weak hydrogen bonds. The inorganic fragment CuCl–2 is partially disordered, which appears as “splitting” of the positions of the copper atom and one of the chlorine atom. In compound II, the inorganic fragment occurs as an unusual trigonal-planar CuBr2–3 anion; the N,N,N′,N′-tetraallylpiperasinium cation is not involved in metal coordination.

The crystals of copper(I) π-complexes with N-allyl piperazine derivatives, [C3H5NH(CH2)4NH2]Cu2Cl4(I) and [C3H5NH(CH2)4NHC3H5]0.5CuCl2(II), were prepared by alternating-current electrochemical synthesis. X-ray diffraction study showed that compounds Iand IIcrystallize in the monoclinic system: for I, space group P21/a, a= 10.254(4) A, b= 12.306(4) A, c= 10.656(4) A, γ = 98.83(3)°, V= 1329(2) A3, Z= 4, R= 0.0457 for 1334 independent reflections; for II, space group P21/n, a= 10.187(2) A, b= 7.283(2) A, c= 10.480(3) A, γ = 100.72(2)°, V= 764.0(6) A3, Z= 4, R= 0.0371 for 1025 independent reflections. The structure of Iis composed of {Cu2Cl4(C7H16N2)}2dimers linked by fairly strong (N)H···Cl hydrogen bonds (2.35(4) A). The structure of IIconsists of centrosymmetrical dimeric Cu2Cl42–anions, whose copper atoms coordinate the allyl groups of different centrosymmetrical organic cations. The dimer–ligand chains are stretched along the [\( {11} \)0] direction and are joined by hydrogen contacts (N)H···Cl (2.62(4) A).

The function of the solvent in the self-assembling mode of [CuCl] with tetrahydrothiophene is reported. Copper(l) chloride has been used in the form of [CuCOCl] n , which is slightly soluble in the most common solvents, and to allow an homogeneous phase reaction. The reaction of [CuCOCl] n with THT gave [(CuCl)2(THT)3] x ,1, in CH3OH, [(CuCl)(THT)2] x ,2 in THF [(CuCl)(THT)] x ,3, in CH2Cl2, and [(CuCl)3(THT)2] x ,4, in DME. Compound1 consists of polymeric chains of centrosymmetric Cu2Cl2 dinuclear units bridged by THIT molecules running parallel to the [101] axis. In the structure of2 we found polymeric layers generated from the [(CuCl)(THT)] asymmetric unit by the center of symmetry and by the twofold axis. In compound3 the structure consists of layers generated through the center of symmetry by the [(Cu2Cl2)(THT)2] asymmetric unit, while4 consists of layers generated through the center of symmetry by the [(Cu3Cl3)(THT)2] asymmetric unit. Crystallographic details are as [ollows:2 is monoclinic, space group P21/c.a=9.657(3) A,b=6.441(2) A,c=11.459(3) A,\=111.96(2)°,V=661.0(4) A3. andR=0.075;3 is monoclinic, space group P21/n,a=19.327(7) A,b=6.703(2) A,c=10.116(3) A,s=103.04(3)°,V=1276.7(7) A3 andR=0.043:4 is triclinic, space group Pl,a=12.513(2) A,b=6.698(1) A,c=9.651(1) A,α=91.98(1)°,\=107.86(1)°,γ=74.59(1)°,V=741.2(2) A3, andR=0.044.

For the first time we have synthesized and studied by X-ray structural analysis two novel copper(I) chloride π-complexes with diallylamine (DAA): [H(DAA)]2Cu7Cl9·H2O (D) and 2CuCl·DAA (E). Compound D is isostructural to the complex [H(DAA)]2Cu7Br9·H2O studied earlier: space group Pnam, a=15.934(8), b=14.817(6), c=11.368(6) A, V=2684(4) A3, and Z=4 for [(C6H12N)2 Cu7Cl9·H2O]. Crystals E are triclinic: space group P1, a=7.373(2), b=9.743(4), c=11.351(8) A, α=84.05(4), β=101.26(4), γ=103.31(3)°, V=914(2) A3, and Z=2 for [Cu4Cl4·(C6H11N)2]. The layers of the structure are formed by combining the armchair-shaped cycles Cu4Cl4 via the tridentate DAA molecules.

Intrinsic γ-Copper (I) Chloride is an ionic I-VII compound semiconductor material with relatively low conductivity. To fabricate an efficient electroluminescent device based on CuCl nanocrystals (NC) the conductivity of the CuCl NC film should be relatively high. In order to improve the conductivity of CuCl films, nanocrystals were embedded in a highly conductive polymer (Polyaniline) and deposited on glass substrates via the spin-coating method. The deposited films were heated at 140°C for durations between 1 and 12 hours in vacuo. The room temperature UV-Vis absorption spectra for all CuCl films showed both Z1,2 and Z3 excitonic absorption features and the absorption intensity increased as the anneal time increased. Room temperature photoluminescence (PL) measurements of the hybrid films reveal very intense Z3 excitonic emission. Room temperature X-ray diffraction (XRD) confirmed the preferential growth of CuCl nanocrystals whose average size is ≈40 nm in the orientation. Resistivity measurements were carried out using a four-point probe system, which confirmed that the resistivity of the composite film was ≈500 Ω/cm. This is an improvement when compared to the vacuum evaporated CuCl thin films.

The reaction of CuCl with silicon containing as impurities Al, Fe, Ca and Ti or with some silicides (Si2Ca, Si2Fe, Si2Ti) has been investigated in the temperature range 250–310 °C. For the reaction between CuCl and commercial Si, it has been found that at 282 °C, the aluminium promotes the reaction between Cu3Si and CuCl while its rate of consumption is greatly decreased by the presence of iron impurity. The combined action of these two impurities improves the quantity of the copper-silicon alloy formed. In the presence of silicides, the reaction with CuCl leads to copper formation with a high degree of dispersion.

A method of synthesis of fluorinated alkoxyethynyl ketones is described, by acylation of terminal acetylenic compounds with fluoracyl chlorides in the presence of CuCl.

The effect of an SiO2 layer thermally grown or partially removed by standard cleaning treatment on the reaction between powder silicon or Si(100) wafer and solid or gaseous copper(I) chloride was studied. The rate of the reaction increases with decreasing oxide layer thickness, which is attributed to the formation of defects, such as pinholes, in the oxide layer, allowing the vapour transport of CuCl to the silicon surface. X-ray diffraction patterns indicate that the proportion of reaction products Cu3Si, Cu5Si and copper changes with thickness of SiO2. In order to explain the presence of Cu5Si and copper for thick layer and cavity formation inside Cu3Si nuclei, it has been suggested that the reaction between Cu3Si and CuCl is promoted.

Copper(I) complexes [CuClL]2 (L=Py, 4-PhPy, 4-MePy, 4-Me2NPy, and 4-PhCOPy) react with dioxygen in dichloromethane according to the rate law: r=KD1/2 k2 [CuClL]21/2[O2] where KD is the dissociation constant of the equilibrium [CuClL]2 ⇋2 CuCIL and k2 the second order rate constant of the reaction of the latter with dioxygen.

The first copper(I) complex oftrans-cinnamonitrile,trans- (PhCHCHCN)3 · CuCl, has been prepared. Its infrared and Raman spectra indicate that bonding of the ligands to the metal occursvia the nitrogen atoms and that coordination induces a slight strengthening of the C≡N bond and weakening of the C=C bond. Single crystals of the compound and the isostructural bromide have been obtained, and the structure of the latter determined by x-ray methods. A photochemical study, performed on CuCl solutions in pure nitrile or in cinnamonitrile diluted in MeOH have shown the photoassistance of thetrans-cis nitrile isomerization by thetrans- (PhCHCHCN)3 · CuCl complex. The quantum yields of this isomerization were compared.

The crystal and molecular structures of the title compounds CuCl·C8H14 and AgNO3·C8H14, have been determined by single-crystal X-ray diffraction techniques, and refined by full-matrix least squares. Both compounds crystallize in the orthorhombic space groupPbca witha=6.191(7),b=12.456(2),c=23.272(4) A for CuCl·C8H14, anda=7.383(2),b=9.825(2),c=26.980(5) A for AgNO3·C8H14;Z=8 in both cases. FinalR factors are 0.047 and 0.029 respectively. The cyclooctene ring has the twist chair-chair (TCC) conformation, with approximateD 2 symmetry, in both compounds, and the torsion angles around the double bonds are −134.2(4) and −137.0(4)° respectively. Slight lengthening of the metal-complexed double bond is attributed to enhanced olefin → metal σ-donation of thetrans bond.

Reaction of vinylhalides (vinylbromide, 1-chloro-1-cyclopropylethylenes) with CH2N2 in the presence of (PhO)3P·CuCl leads to formation of the corresponding halocyclopropanes with 13–15% yields, while reaction of CH8N2 with alkylbromide under the same conditions gives the product of formal methylene introduction, 4-bromobut-1-ene (yield 58%) with insignificant formation (∿1%) of bromomethylcyclopropane.

The equilibrium vapour pressure of the solid complex, CuCl·MeCN, was measured at several temperatures. The enthalpy and entropy changes according to the following complex formation were determined: CuCl(s)+ MeCN(g)→CuCl·MeCN(s); ΔH=−56.9 kJ mol−1 and ΔS=−150 J mol−1K−1, respectively. Vapour pressure osmometry shows that a monomer-dimer equilibrium of CuCl exists in the acetonitrile solution. The equilibrium constant was found to be 0.93±0.08. A gas chromatographic technique was employed to determine the monomeric species as [Cu(MeCN)4]Cl.