P. Karagiannidis

Synthesis and photochemical study of Cu(I) complexes with tri-p-tolylphosphine and heterocyclic thiones. The crystal structure of [CuCl(pymtH)(p-CH3C6H4)3P]2

Reactions of [Cu(tptp)X]4 (tptp=tri-p-tolyl-phosphine, XCl, Br or I) with heterocyclic thiones (L) [L=pyridine-2-thione (py2SH), pyrimidine-2-thione (pymtH), 1,3-thiazolidine-2-thione (tzdtH), 1-methyl- 1,3-imidazoline-2-thione (meimtH), benz-1,3-imidazoline-2-thione (bzimtH2) and quinoline-2-thione (qntH)] yield binuclear complexes of the general formula [Cu(tptp)(L)X]2. The complexes have been characterized by elemental analyses, IR, UV-Vis and 1H NMR spectroscopy. The photochemical behaviour of these complexes in chloroform solutions has been investigated. Irradiation causes the release of the phosphine and the formation of dinuclear compounds containing a Cu2S2 core. The crystal structure of [Cu(tptp)(pymtH)Cl]2 has been determined by single-crystal X-ray diffraction methods. The red crystals are triclinic, space group P with a=19.512(2), b=10.388(3), c=14.474(2) A, α=99.00(2), β=73.28(1), γ=116.22(2)°, Dcalc=1.394 M m−3, V=1228.2(4) A3 and Z=1. The molecule contains a planar Cu2S2 moiety with CuS bond lengths of 2.356(1) and 2.470(1) A. The CuP and CuCl distances are 2.227(1) and 2.300(1) A, respectively. The Cu···Cu separation is 3.316(0) A.

Mononuclear and binuclear Cu(I) complexes with metal-sulfur ligation

Abstract The synthesis, characterization and electrochemistry of the copper(I)(triphenylphosphine)-chloride, bromide and iodide complexes of pyridine-2-thione (py2SH), pyridine-4-thione (py4SH) and pyrimidine-2-thione (pymtH) and the crystal structure of the complex [Cu(py2SH(PPh3)Br]2 are reported. Crystals of [Cu(py2SH)(PPh3)Br]2 are triclinic, space group P 1 , with a=9.586(4), b=9.562(5), c=13.573(5) A, α=77.56(3), β=73.32(3), γ=62.38(3)° and Z=1. The molecule contains a planar Cu2S2 moiety with bond lengths Cu(1)S(1)=2.383 A and Cu(1)S(1′)=2.392 A and bond angles SCuS=88.5° and CuSCu′=91.5°. The structure has been solved by direct methods with a final R of 0.039. The complex is binuclear, the stereochemistry of the Cu2S2 core is strictly planar. The equivalent copper atoms have pseudotetrahedral geometry. The electrochemical study indicates that the potentials are in the fange of about +0.3 to +1.1 V versus SCE. The synthesis and structure determination at 140 K of Cu(py2SH)(PPh3)2Br is also reported. Crystals are monoclinic, space group P21/n, with a=9.436(3), b=19.168(5), c=19.597(5) A, β=91.31(3)° and Z=4. The metal ion has a distorted tetrahedral geometry with bond lengths CuS=2.302, CuBr=2.462 and CuP=2.263–2.267 A. The structure has been solved by direct methods with a final R of 0.075.

Copper(I) bromide complexes with heterocyclic thiones and triphenylphosphine as ligands. The X-ray crystal structure of copper(I) pyrimidine-2-thione bis (triphenylphosphine) bromide [Cu(PPh3)2(PymtH)Br]

Abstract Reactions of copper(I) bromide with heterocyclic thiones (L) [L = pyridine-2- thione (py2SH), pyridine-4-thione (py4SH), pyrimidine-2-thione (pymtH), 1,3-thiazolidine- 2-thione (tzdtH), 1-methyl-1,3-imidazoline-2-thione (meimtH), benz-1,3-imidazoline-2- thione (bzimtH2), benz-1,3-oxazoline-2-thione (bzoxtH), 5-nitro-2-benz-1,3-imidazoline-2- thione (nbzimtH2), benz-1,3-thiazoline-2-thione (bztzH) and quinazolinone-2-thione (qnotH2)] in the presence of triphenylphosphine yields mononuclear complexes of the general formula [Cu(L)(PPh3)2Br]. The complexes have been characterized by elemental analysis, IR, UV-vis and NMR spectroscopy. The crystal structure of [Cu(PPh3)2(pymtH)Br] has been determined by single-crystal X-ray diffraction methods. The yellow-orange crystals are monoclinic, space group P21/nwith a = 13.035(2), b = 43.660(9), c = 13.446(2) A, β = 90.68(2)°, and Dcalc = 1.352 g cm−3, V = 7652 A3, R(F) = 0.06 7; Rw(F) = 0.069, GOF = 1.19. In both molecules of the asymmetric unit, the pymtH molecule acts as a monodentate ligand through the S atom (CuS = 2.352(3) A).

Study of mixed ligand copper(I) complexes with tri-m-tolyl-phosphine (tmtp) and heterocyclic thiones. Crystal structures of bis[μ-S(benzimidazoline-2-thione)(tmtp) copper(I) chloride] and bis[μ-Br(thiazolidine-2-thione)(tmtp) copper(I)]

Reactions of [Cu(tmtp)X]n (tmtp=tri-m-tolyl-phosphine; X=Cl, Br) with heterocyclic thiones (L) (L=pyridine-2-thione (py2SH), pyrimidine-2-thione (pymtH), 1,3-thiazolidine-2-thione (tzdtH), 1-methyl-1,3-imidazoline-2-thione (meimtH), benz-1,3-imidazoline-2-thione (bzimtH2) and quinoline-2-thione (qntH)) yield binuclear complexes of the general formula [Cu(tmtp)(L)X]2. The complexes have been characterized by elemental analyses and their IR, UV-Vis and 1H NMR spectroscopic data. The photolysis of these complexes in dichloromethane solutions has been investigated. The crystal structures of [Cu(tmtp)(bzimtH2)Cl]2 (I) and [Cu(tmtp)(tzdtH)Br]2 (II) have been determined by single-crystal X-ray diffraction methods. The white crystals of the two compounds are both monoclinic, space group P21/a with a=12.636(8), b=15.325(6), c=13.696(8) A, β=102.76(3)°, Dcalc=1.421(1) Mg m−3, V=2586.5(3) A3 and Z=2 for [Cu(tmtp)(bzimtH2)Cl]2 and space group P21/n with a=15.085(1), b=9.820(3), c=17.263(1) A, β=99.77(3)°, Dcalc=1.494 Mg m−3, V=2520.2(4) A3 and Z=2 for [Cu(tmtp)- (thzdtH)Br]2. The chloro complex contains a planar Cu2S2 moiety with CuS bond lengths of 2.386(2) and 2.444(1) A and CuP and CuCl distances equal to 2.251(1) and 2.391(2) A, respectively. The Cu···Cu separation is 2.764(1) A. The bromo molecule forms a planar Cu2Br2 frame with CuBr bond lengths of 2.5182(2) and 2.5971(8) A and CuP and CuS distances equal to 2.240(1) and 2.307(1) A, respectively. The Cu···Cu separation is 3.3471(7) A. Rationalization of the above described properties in terms of stereoelectronic factors governing bond formation is attempted by means of EHT computations.

Synthesis and characterization of copper(I) halide complexes with heterocyclic thiones and triphenylphosphine as ligands. The X-ray crystal structure of copper(I) 1-methyl-1,3-imidazoline-2-thione bis(triphenylphosphine)bromide, [Cu(PPh3)2-meimtH)Br]

Abstract Following our earlier reports on copper(I) mixed-ligand complexes with heterocyclic thiones and triphenylphosphine, we now report the isolation of 12 new complexes of the general formula [Cu(PPh3)2(L)X] [L = 1-methyl-1,3-imidazoline-2-thione (meimtH), 5-methyl-2-benz-1,3-imidazoline-2-thione (mebzimtH2), purine-6-thione (pur6SH), quinoline-2-thione (qn2SH) and X = Cl, Br, I], and their characterization by various physico-chemical methods. The crystal structure of the complex [Cu(PPh3)2(meimtH)Br] is also reported. Crystals are prisms, space group P 1 with a = 9.988(3), b = 10.212(2), c = 21.066(5) A, α = 94.86(2), β = 91.70(2), γ = 119.16(2)° and Z = 2. The metal ion has a distorted tetrahedral geometry with bond lengths CuS = 2.375(1), CuBr = 2.509(0), CuP(1) = 2.268(1) and CuP(2) = 2.281(1) A. The structure has been solved by single-crystal X-ray diffraction methods with a final R of 0.0330 for observed reflections with Fo ⩾ 6.0β(Fo).

Silver(I) complexes with heterocyclic thiones and tertiary phosphines as ligands. Part 4. Dinuclear complexes of silver(I) bromide: the crystal structure of bis[bromo-(pyrimidine-2-thione)(triphenylphosphine)silver(I)]

Abstract Mixed-ligand complexes of the formula [Ag(PPh 3 )(L)Br] 2 were obtained by treatment of various heterocyclic thiones L {L=pyridine-2-thione (py2SH), pyrimidine-2-thione (pymtH), benz-1,3-imidazoline-2-thione (bzimtH 2 ), benz-1,3-thiazoline-2-thione (bztztH), 1-methyl-1,3-imidazoline-2-thione (meimtH) and 5-methoxy-benz-1,3-imidazoline-2-thione (5MeObzimtH 2 )} with equivalent quantities of silver(I) bromide and triphenylphosphine in dry acetone. The compounds were characterized by their IR, far-IR, UV–Vis and 1 H NMR spectroscopic data. The crystal structure of [Ag(PPh 3 )(pymtH)Br] 2 was determined by single-crystal X-ray diffraction methods. The complex exhibits a planar Ag 2 Br 2 moiety in which each of the doubly bromine-bridged Ag(I) centres is further bonded to one phosphine P and one thione S atom.

Preparation and spectral studies of dinuclear mixed-ligand copper(I) complexes. The crystal structure of bis[μ-s(pyridine-2-thione)(tmtp) copper(I) bromide]

Abstract [Cu(tmtp)Br]n (tmtp = tri-m-tolylphosphine) reacts with heterocyclic thiones (L) [L = pyridine-2-thione (py2SH), 1,3-thiazolidine-2-thione (tzdtH), benz-1,3-imidazoline-2-thione (bzimtH2), benz-1,3-thiazoline-2-thione (bztzdtH), imidazoline-2-thione (imtH), benz-1,3-oxazoline-2-thione (bzoxtH2), 5-nitrobenz-1,3-imidazoline-2-thione (nbzimtH2), and 5-methyl-benz-1,3-imidazoline-2-thione (mebzimtH2)] to give binuclear complexes of the general formula [Cu(tmtp)(L)Br]2. These complexes have been characterized by various spectroscopic methods. The crystal structure of the pyridine-2-thione complex has been determined by single-crystal X-ray diffraction methods. The molecule contains a planar Cu2S2 moiety with CuS bond lengths of 2.3348(9) and 2.4879(7) A. The CuBr and CuP distances are 2.4929(1) and 2.2525(4) A, respectively, whereas the Cu⋯Cu separation is 2.6906(1) A.

Silver(I) complexes with heterocyclic thiones and tertiary phosphines as ligands Part 2. Mononuclear complexes of silver(I) nitrate. The crystal structures of [Ag(PPh3)2(pytH)2]NO3 and [Ag(PPh3)2(pymtH)]NO3

Abstract The preparation and characterization of mononuclear silver(I) nitrate complexes with various heterocyclic thiones (pytH = pyridine-2-thione, pymtH = pyridine-2-thione, quin2tH = quinoline-2-thione, izdtH = thiazolidine-2-thione, mbzimtH2 = N=methyl-benzimidazoline-2thione, pur6tH = purine-6-thione) and triphenylphosphine as ligands are described. The X-ray determination of the crystal structures of [Ag(PPh3)2(pytH)2]NO3 (I) and [Ag(PPh3)2(pymtH)]NO3 (II) is also reported. Compound I crystallizes in the monoclinic system, space group P21/c, with a = 12.588(3), b = 18.234(5), c = 18.527(5) A , β = 96.29(2)°, V = 4227 A 3 and Z = 4 , while crystals of II are triclinic, space group P 1 , with a = 10.084(2), b = 13.508(3), c = 14.326(3) A , α = 77.43(2), β = 78.14(2)°, V = 1646 A 3 and Z = 2 . The coordination geometry about the silver atom is distorted tetrahedral in I, with one nitrate ion bridging two adjacent complex molecules via strong hydrogen bonds with the thione NH groups. The structure of II consists of almost trigonal-planar AgP2S units and strongly distorted nitrate ions hydrogen bonded to the protonated nitrogen atoms of the heterocyclic thione ligands. The electronic factors imposing the above difference in coordinating behavior are investigated by means of semi-empirical molecular orbital considerations.

Copper(I) complexes with tri-o-tolylphosphine and heterocyclic thione ligands. Crystal structures of [(pyrimidine-2-thione)(tri-o-tolylphosphine)copper(I) chloride] and [(pyridine-2-thione)(tri-o-tolylphosphine)copper(I) iodide]

Abstract Copper(I) complexes of the general formula [Cu(totp)(L)X], where X = Cl, I; totp = tri-ortho-tolylphosphine; L = pyridine-2-thione (py2SH), pyrimidine-2-thione (pymtH), 1,3-thiazolidine-2-thione (tzdtH), 1-methyl-1,3-imidazole -2-thione (meimtH), benz-l,3-imidazoline-2-thione (bzimtH2) and quinoline-2-thione (qntH) were prepared and characterized by their IR, UV-Vis and 1H NMR spectroscopic data. The behaviour of the complexes upon photolysis in chloroform solutions has been investigated. The structures of [Cu(totp)(pymtH)Cl] and [Cu(totp)(tzdtH)I] were determined by X-ray diffraction: [Cu(totp)(pymtH)Cl] crystallizes in the trigonal space group P3 with a = 22.433(4), b = 22.433(4), c = 9.526(3) A, γ=120° and Z = 6; [Cu(tzdtH)(totp)I] crystallizes in the monoclinic space group P21/n with a = 17.111(2), b = 10.505(1), c = 14.823(1) A, β = 108.30(1)°, Z = 4. In both complexes the coordination around Cu is approximately trigonal planar. Steric protection at the central metal by the three methyl groups neighbouring the donor phosphorus of the phosphine ligand is likely to explain the preferential formation of three-coordinate complexes.

Cu(I) Complexes with heterocyclic thiones and triphenylphosphine as ligands. The crystal structure of [Cu(tzdtH)2 (PPh3)2]NO3

Abstract The reactions of bis(triphenylphosphine)copper(I) nitrate with heterocyclic thiones (L) [L = pyridine-2-thione (py2SH), pyridine-4-thione (py4SH), pyrimidine-2-thione (pymtH), 1,3-thiazolidine-2-thione (tzdtH), 1-methyl-1,3-imidazoline-2-thione (meimtH), benz-1,3-imidazoline-2-thione (bzimtH 2 ), benz-1,3-thiazoline-2-thione (bztzH), benz-1,3-oxazoline-2-thione (bzoxtH), 5-nitro-2-benz-l,3-imidazoline-2-thione (nbzimtH 2 ) and quinazolinone-2-thione (qnotH 2 )] lead to the formation of mononuclear complexes of the general formula [Cu(L) 2 (PPh 3 ) 2 ]NO3. The complexes have been characterized by elemental analysis, infrared, UVVis and NMR spectroscopy. The crystal structure of [Cu(tzdtH) 2 (PPh 3 ) 2 ]NO 3 has been determined by single-crystal X-ray diffraction methods. The colorless crystals are monoclinic, space group P 2 1 / c with a = 16.314(2), b = 9.981(2), c = 25.799(3) A, β = 89.39(1)°, V = 4200 A 3 and Z = 4.