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The self assembly of AgX with the sulfur-containing multidentate ligand α,α′-bis(8-thioquinoline)-m-xylene (m-XYTQ) affords two isomorphous complexes [Ag(m-XYTQ)]nXn (X=ClO4 1; X=BF4 2). Single crystal X-ray analyses revealed the complexes to contain linear cationic chains of [Ag(m-XYTQ)]nn+ in helical arrangement and the anions are discrete. Intramolecular π⋯π stackings pack the asymmetric units [Ag(m-XYTQ)] in shelves-like arrays while interchain π⋯π interactions between racemic chains constructed the 2D network. The key to helix formation is the folding at the sulfur sites of the spacer xylylene in the ligand. The complexes were also characterized by 1H NMR and IR.

From the reactions of [Et 4 N] 2 MoSe 4 and M(PPh 3 ) n L(M = Cu, Ag, Au: L = Cl, NO 3 : n = 1−2)in univalent comage metal and an MoSe 4 2 unit, [MoSe 4 (CuPPh 3 )PPh 3 ) 2 ] ( 1 ), [MoSe 4 (AgPPh 3 ) Ag(PPh 3 ) 2 ] ( 2 ), [MoSe 4 (Ag-PPh 3 ) 2 ] ( 3 ), [MoSe 4 (AuPPh 3 ) 2 ] ( 4 ), [MoSe 3 )Set(CuPPh 3 ) 3 Cl] ( 6 ), have been isolated and characterized by 93 Mo NMR, IR and Raman spctra. The 93 Mo chemical shifts are mainly dependent upon the shielding effects from the number of the coinage metal atoms around the Mo atom and the geometric structure of the molecule. The shielding order is Au > Cu > Ag. The crystal structure of 4 has been determined by X-ray single-crystal diffraction analysis. It crystallizes in the triclinic space group P -1 with cell constants a = 9.570(2), b = 10.755(2), c = 19.837(4) A : α = 89.59(3), β = 80.37(3), γ = 68.33(3)° and Z = 2 . The molecule has a linear structure with an average Mo distance of 2.846(2) A.

A novel tetranuclear Mo–Cu–Se cluster compound (Ph 4 P) 2 [MoCu 3 OSe 3 Cl 3 (Py)] (Py=pyridine) has been synthesized by the reaction of (Ph 4 P) 2 [MoSe 4 ], CuCl and pyridine in CH 3 CN. X-ray single crystal diffraction analysis reveals that the anion structure consists of an incomplete cubane-like MoCu 3 Se 3 core. The average Mo–Cu and Mo–Se distances are 2.704(7) and 2.394(2) A and the average angles of Se–Mo–Se, Se–Cu–Se, and Se–Cu–Cl are 109.4(2), 104.5(3), and 112.3(3)°, respectively.

The synthetic reactions and spectroscopic studies of molybdenum(tungsten)-copper-sulfur cluster compounds, which can be prepared by the stepwise or unit construction reactions through the successive addition of CuL (L = Cl, Br, R2dtc) across six edges or four faces of MS4 (M = Mo, W) tetrahedra, are described. A series of Mo(W)CuS cluster compounds, (Et4N)2[MoCu2S4(S2CNEt2)2] (1) (Et4N)2- [MoCu2S3O(S2CNC4H8)2 (2), [MoCu2S4(dppe)2] (3) (dppe = bis(diphenylphosphine ethane, (Et4N)2[MoCu3S4(S2CNEt2)3] (4), (Et4N)2[Mo2Cu4S8(S2CNEt2)2] (5), (Et4N)2[Mo2Cu4S6O2(S2CNC4H8)2] (6), [Mo2Cu4S8(dppm)2] (7), [Mo2Cu4S6O2(dppm)2] (8) (dppm = bis(diphenylphosphine)methane), (Et4N)4[MoS4Cu10Br12] (9), (Et4N)4[WS4Cu10Br12] (10), have been prepared and characterized by IR and 95Mo NMR spectra. The polynuclear WCu cluster compound (Et4N)4[WS4Cu10Br12] (10) is characterized by single crystal X-ray diffraction analysis. The anion structure consists of a central WS4 moiety, an octahedral Cu6 and a tetrahedral Cu4 array. The average WCu and WS distances are 2.726(8) and 2.247(7) A and the average angles of SWS, SCuS and SCuBr are 109.5(3), 104.1(4) and 112.6(3)°, respectively.

A novel polynuclear cobalt complex [Co 7 Na 2 (1,2-OSC 6 H 4 ) 8 (DMF) 12 ] was obtained from the reaction of CoBr(PPh 3 ) 3 with Na 2 (1,2-OSC 6 H 4 ) (H 2 mp= o -mercaptophenol) in DMF and its crystal structure has been determined by single crystal X-ray diffraction analysis. The molecular structure contains nine layers. The cobalt and sodium atoms are arranged in nearly linear chain configuration and bridged by 1,2-OSC 6 H 4 2− and DMF ligands via their oxygen atoms.

A new compound [Na3Co4(μ3-O)2(mpo)8(DMF)4]Br·2DMF (1) was prepared by reacting CoBr(PPh3)3 and Nampo (mpo = 2-mercaptopyridine-N-oxide), and structurally characterized by X-ray diffraction methods. The title compound crystallizes in the triclinic space group P1 with a = 13.393(7), b = 14.00(1), c = 13.029(4) A, α = 92.29(4), β = 110.56(3), γ = 115.32(4)°, V = 2015(2) A3, Z = 1 and R (Rw) = 0.047 (0.053) for 1820 reflections (I > 3 σ(I)). The complex contains four cobalt atoms in the form of a square plane with indirect metal-metal bonds. Each Co atom is coordinated by two bidentate mpo ligands with StOb-D and StOb-T coordination modes, respectively. Two Co2(mpo)4O groups each bridged by μ3-O in the Na3Co4 core are linked by Na3 through the oxygen atoms of the mpo ligands and the bridging μ3-O atoms to form a dumbbell-like structure. The structure of the symmetric tetracobalt cation [Na3Co4(μ3-O)2(mpo)8(DMF)4]+ possesses a crystallographic inversion center through the Na(1) atom. The relevance of the spectroscopic and magnetic properties to the structure of 1 is also discussed.

The reaction of Co(PPh3)3Cl and K2S2C=C(CN)2 in a 1:1 molar ratio in MeCN led to S-C bond cleavage of [S2C=C(CN)2]2− and allowed isolation of a pentanuclear cobalt cluster compound [Co5(μ3-S)4{μ-SC=C(CN)2}2(PPh3)4] 1 and an octanuclear cobalt cluster compound with mixed Co(I) and Co(II), (PPh4)[Co8(μ4-S)6Br2Cl2(PPh3)4] 2; the core in 1 is a highly distorted Co5 trigonal bipyramid, while that in 2 is a Co8 cube.

A new dinuclear pentacoordinate ironsulfur compound (Et 4 N) 2 [Fe 2 (1,2-OSC 6 H 4 ] ( 1 was synthesized and the structure of 1·2CH 3 CN was determined to be monoclinic, P 2 1 / n , M r = 950.97, with crystal data a = 11.580(2), b = 16.731(6), c = 12.869(2) A ; β = 98.07(2)°, V = 2468.6 A 3 , Z = 2, D x = 1.279 g cm −3 . From the 2242 independent reflections with I ⩾ 3σ( I o ), the final R converged to 0.069. The centrosymmetric anion of 1 is a dimer of [Fe(mp) 2 ] − bridged by the alkoxy groups of the two bridging mp 2− . The atom Fe(III) is in distorted trigonal bipyramidal environment with O(1) and O(2) as the two apical atoms and O(1′)S(1)S(2) forming the equatorial plane. Both 1 H NMR and CV measurements in DMSO and CH 3 CN showed the existence of species D (CH 3 CN) or M (DMSO), respectively, from the equilibrium (1). The dissociation of 1 into M in strongly polar solvent is further evidenced by 1 H NMR in DMF of intermediate polarity, which gave a ratio of D:M = 8:1. Mossbauer effect measured at 77 K indicated that the ground state spin of Fe(III) in 1 ·2CH 3 CN is .