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Crystallization of the copper(i) halides (CuX; X = Cl, Br, I) with N,N'-diphenylthiourea ('dptu' = (PhNH)(2)CS) in 1 : 2 ratio from acetonitrile solution in ambient conditions yields a mononuclear isomorphous series of complexes of the form [XCu(dptu)(2)].H(2)O, an unusually complete array, with the central copper atoms in quasi-trigonal planar environments, as shown by single crystal X-ray studies, in turn providing a platform for comparative spectroscopic studies. Under anhydrous conditions, anhydrous compounds may be obtained, a full series again being accessible, but now of the binuclear form [(dptu)XCu(mu-S-dptu)(2)CuX(dptu)], the chloride being a bis(acetonitrile) solvate, the isomorphous bromide and iodide pair being unsolvated. A (solvated) sulfate salt is found to be of the form [Cu(dptu)(2)](2)(SO(4)), providing a novel example of a copper(i) atom being (quasi-)linearly coordinated by the pair of unidentate (dptu) sulfur ligands, Cu-S 2.1770(5), 2.1811(5) A, S-Cu-S 162.18(2) degrees . The nu(CuX) vibrational frequencies are assigned in the far-IR spectra of [XCu(dptu)(2)].H(2)O (X = Cl, Br, I) at 274, 207, and 190 cm(-1) respectively. The broadline static (65)Cu NMR spectra of [Cl(2)Cu(2)(dptu)(4)].2CH(3)CN and [X(2)Cu(2)(dptu)(4)] (X = Br, I) have been recorded at 9.4 and 7.05 T, and the spectra have been analysed to yield the (65)Cu nuclear quadrupole coupling and chemical shift parameters. The (63,65)Cu nuclear quadrupole resonance frequencies of [XCu(dptu)(2)].H(2)O (X = Cl, Br, I) have also been measured, and the resulting (65)Cu quadrupole coupling constants are ca. 4x those of the dimeric [X(2)Cu(2)(dptu)(4)] compounds.

Several synthetic strategies using copper(I) starting materials or copper(II) compounds and an in situ sulfite reductant have been used to systematically explore the chemistry of copper(I) complexes with thiourea and substituted thiourea ligands. This has resulted in the discovery of several new complexes and methods for the bulk synthesis of some previously reported complexes that had been prepared adventitiously in small quantity. The new complexes are (tu = thiourea, dmtu = N,N'-dimethylthiourea, etu = ethylenethiourea): [I(4)Cu(4)(tu)(6)].H(2)O, [Cu(4)(tu)(10)](NO(3)).tu.3H(2)O, [BrCu(dmtu)(3)], [ICu(dmtu)(3)](2), [BrCu(etu)(2)](2), [ICu(etu)(2)], [ICu(etu)(2)](3). [I(4)Cu(4)(tu)(6)].H(2)O has an adamantanoid structure, with four terminal iodide ligands and six doubly bridging tu ligands. In contrast to this, [Cu(4)(tu)(10)](NO(3)).tu.3H(2)O contains a tetranuclear cluster in which four of the tu ligands are terminal and the other six are doubly bridging. [BrCu(dmtu)(3)] is a mononuclear complex with tetrahedral coordination of copper by one bromide and three dmtu ligands, whereas [Cu(dmtu)(3)](2)I(2) has a centrosymmetric dimeric cation with two uncoordinated iodides, four terminal dmtu and two doubly bridging dmtu ligands, [(dmtu)(2)Cu(mu-S-dmtu)(2)Cu(dmtu)(2)]I(2). A reversal of this monomer to dimer trend from bromide to iodide is seen for the etu counterparts: [BrCu(etu)(2)](2) is a centrosymmetric dimer with two doubly bridging etu ligands, [(etu)BrCu(mu-S-etu)(2)CuBr(etu)], whereas [ICu(etu)(2)] is a trigonal planar monomer, although the novel [I(3)Cu(3)(etu)(6)] is also defined. Infrared and Raman spectra of the synthesized complexes were recorded and the metal-ligand vibrational frequencies have been assigned in many cases. The results confirm previously observed correlations between the vibrational frequencies and the corresponding bond lengths for complexes of the unsubstituted tu ligand. A mechanochemical/infrared method was used to synthesize [I(3)Cu(3)(etu)(6)] from CuI and etu, and to demonstrate the polymorphic transition from [ICu(etu)(2)] to [I(3)Cu(3)(etu)(6)].

Single-crystal structural characterizations confirm the existence of the unusual 1 : 4 copper(I) halide : unidentate ligand adducts [Cu(CNt-Bu)4]X for X = Cl, Br (two forms), I (the chloride and one form of the bromide being solvated) with crystal packing dominated by stacks of interleaving cations. Cu-C range between 1.941(2) and 1.972(4) A. The structure of the 1 : 2 chloride complex is also recorded, being [ClCu(CNt-Bu)2], with the copper(I) atom environment trigonal planar, while CuCN : (CNt-Bu) (1 : 1) is a single-stranded polymer which spirals about a crystallographic 3-axis (CN scrambled), the ligands being pendant from the ...CuCNCuCN... string. The (5Cu static broadline NMR spectra of [Cu(CNt-Bu)4]I and [Cu(CNt-Bu)4]Br.H2O in the solid state exhibit dominant, narrow -1/2 <--> +1/2 central transition resonances and associated +/-1/2 <--> +/-3/2 satellite transition resonances which are characteristic of first-order quadrupole broadened systems, while associated high-resolution 65Cu MAS NMR data provide accurate measurement of the 65Cu isotropic chemical shifts. Both approaches provide complete data on the quadrupole and chemical shift interactions which contribute to these spectra. Far-IR spectra of products of reactions involving a range of CuX : t-BuNC ratios reveal the existence of 1 : 1.5 adducts for X = Br, I. Metal-carbon and metal-halogen bands are assigned in the far-IR spectra, which indicate a binuclear double halogen-bridged structure for the 1 : 1.5 complexes.

The tris(triphenylphosphine)copper(I) complexes [(PPh3)3CuX] for X = Cl (1), Br (2), I (3), ClO4 (4), BF4 (5), [(PPh3)3CuCl].CH3CN (1a), [Cu(PPh3)3(CH3CN)]X for X = ClO4 (6), BF4 (7), and [Cu(PPh3)3(CH3CN)]X.CH3CN for X = SiF5 (8), PF6 (9) have been studied by solid state 31P CP/MAS NMR spectroscopy together with single crystal X-ray diffraction for compounds (6)-(9), the latter completing the availability of crystal structure data for the series. Compounds (1)-(5) form an isomorphous series in space group P3 (a approximately 19, c approximately 11 A) with three independent molecules in the unit cell, all disposed about 3-fold symmetry axes. Average values (with estimated standard deviations) for the P-Cu-P, P-Cu-X bond angles and Cu-P bond lengths in compounds (1)-(3) are 110.1(6) degrees, 108.8(6) degrees and 2.354(8)A and 115.2(6) degrees, 102.8(9) degrees and 2.306(9)A for compounds (4) and (5). For the acetonitrile solvated compound (1a), the corresponding parameters are 115(4) degrees, 103(3) degrees and 2.309(3)A. The solid state 31P CP/MAS NMR quadrupole distortion parameters, dnu Cu, for (1)-(3) and (1a) are all less than 1 x 10(9) Hz2, despite the changes in donor properties of the halide in (1)-(3), and the coordination geometry of the P3CuX core in (1a). Change of anion to ClO4- and BF4- in compounds (4) and (5) results in a significant increase of dnu Cu to 4.4-5.2 10(9) Hz2 and 5.2-6.0 x 10(9) Hz2, respectively. Compounds (6) and (7) crystallise as isomorphous [Cu(PPh3)3(CH3CN)]X salts in space group Pbca, (a approximately 17.6, b approximately 22.3, c approximately 24.2 A), while compounds (8) and (9) crystallize as isomorphous acetonitrile solvated salts [Cu(PPh3)3(CH3CN)]X.CH3CN in space group P1(a approximately 10.5, b approximately 13.0, c approximately 19.5 A, alpha approximately 104, beta approximately 104, gamma approximately 94 degrees). The P3CuN angular geometries in all four compounds are distorted from tetrahedral symmetry with average P-Cu-P, P-Cu-N angles and Cu-P bond lengths of 115(4) degrees, 103(4) degrees and 2.32(1)A, with dnu Cu ranging between 1.3 and 2.5 x 10(9) Hz2. The solid state 29Si CP/MAS NMR spectrum of the pentafluorosilicate anion in compound (8) is also reported, affording 1J(29Si, 19F) = 146 Hz.