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The flexible multidentate ligand O,O′-bis(8-quinolyl)-1,8-dioxaoctane (ODOQ) reacted with AgX (X = ClO4−, BF4−, CF3SO3−, or CF3CO2−) to give four new complexes [Ag(ODOQ)]nXn: X = ClO4−1; X = BF4−2; X = CF3SO3−3, and [Ag(ODOQ)(CF3CO2)]n4. All four complexes have been characterized by elemental analyses, IR and 1H NMR spectroscopy. Single crystal X-ray analyses showed that they have similar 1-D extended architectures with each ligand in “∼” shape, while the chains are alternately and parallelly arranged with the silver(I) atoms as the backbone to form double helical mesomeric strands. The structures are controlled more by the spacer (CH2)6 than by the anions: the versatile coordination geometry of the silver(I) atom is trigonally bonded but changes to distorted tetrahedral or trigonal bipyrimidal via weak Ag⋯O interactions. In addition, face-to-face π⋯π (in 1–4) and edge-to-face C–H⋯π (in 3) interactions as well as hydrogen bonds C–H⋯O and C–H⋯F between adjacent strands assemble the cations in 1–3 or neutral molecules in 4 into an extended network.

The flexible linear multidentate ligands 1,5-bis(8-quinolylsulfanyl)-3-oxapentane (OESQ) and 1,8-bis(8-quinolylsulfanyl)-3,6-dioxaoctane (ODSQ) reacted with silver(I) perchlorate affording the simple mononuclear complexes [Ag(OESQ)]ClO41 and [Ag(ODSQ)]ClO42, respectively. However, with silver(I) nitrate, novel metallosupramolecular complexes [Ag4(ODSQ)2(η1-NO3)2(η2-NO3)2] 3 and [Ag4(OESQ)(ODSQ)(η1-NO3)2(η2-NO3)2]·H2O 4 were obtained, in which the co-ordination motifs [Ag(OESQ)]+ and [Ag(ODSQ)]+ are spontaneously self-assembled by sulfur-bridged silver(I) ions into tetrametallotricyclic molecules containing the same or mixed building blocks. All four complexes have been characterized by elemental analyses, IR and 1H NMR spectroscopy, and single crystal X-ray diffraction methods. The possible self-assembly process has been discussed with the aid of electrospray mass spectrometry.

The mixed polymeric cobalt compound [Co3(SCH2CH2S)3(PEt3)3]2[Co2Cl4(µ-O2SEt2)2]1 containing two trimers and one dimer was isolated from the reaction of [CoCl(PEt3)3] with disodium ethane-1,2-dithiolate in 1,2-dichloroethane. It is monoclinic and crystallizes in space group P21/n, with a= 12.481(7), b= 15.70(2), c= 25.84(2)A, β= 97.85(5)° and Z= 2 from 2436 reflections with I > 3.50σ(I), final R= 0.062. X-Ray diffraction established that the two cobalt atoms in the dimer are linked via the oxygen atoms of the diethyl sulfone forming the eight-membered Co2O4S2 ring with a crystallographic inversion centre through the whole dimer. The observed cleavage of the dithiolate C–S bond together with the formation of the bridging diethyl sulfone are discussed. In the trimer of 1, the Co3 isosceles triangle is capped by two bidentate SCH2CH2S2– ligands on either side of the plane with the sulfur atoms bridging the two long Co–Co bonds, while the short Co–Co bond is bridged by the third SCH2CH2S2– ligand. Considering the framework of the Co3P3(SCH2CH2S)3 unit only, there is a pseudo mirror-image plane passing through the Co3P3 plane which bisects the C(31)–C(32) bond. The 1H NMR spectrum of compound 1 demonstrates the retention of the solid-state structure of the trinuclear species in chloroform solution.

The tubular form of crystalline boehmite AlOOH was fabricated using AlCl3·6H2O as the alumina precursor in the presence of N-cetyl-N,N,N-trimethylammonium bromide surfactant, and tubular γ-Al2O3 was obtained by calcination of boehmite AlOOH at 520 °C.

Macroporous rutile titania has been prepared by centrifugation sedimentation and evaporation approaches with TiCl4 as the precursor and polystyrene (PS) spheres as the template. The nanocrystalline rutile titania particles were first synthesized at room temperature, then used to fill the voids between the PS spheres. The macroporous material was obtained after calcination at 450 °C. This is the first report of ordered macroporous rutile titania being obtained by calcination at such a low temperature. XRD results reveal that the titania nanoparticles of the as-synthesized and macroporous materials after calcination are rutile crystalline. SEM images show that the PS spheres and macroporous rutile form three-dimensionally ordered close-packed structures.

The complex [NEt4]2[Mo2Cu5S6O2(Me2NCS2)3] has been prepared by the reaction of CuCl, Na[S2CNMe2],NEt4Br, and [NH4]2[MoS2O2] in dimethylformamide solution. It crystallizes in the orthogonal space group Pnma with a= 23.373(3), b= 17.202(3), c= 12.474(4)A, and Z= 4. The Mo2Cu5S6O2 framework in the anion consists of two defective cubane-like units OMoS3Cu2 and OMoS3Cu3 linked through two weak Cu–S bonds and bridged by two Me2NCS2 ligands. The synthesis of the series of compounds [NEt4]2[M2Cu5S8(Me2NCS2)3], [PPh4]2[M2Cu5S6O2(Et2NCS2)3](M = Mo or W), and [NEt4]2[MoCu3S4(Et2NCS2)3] are reported. Their structures are discussed together with their 1H, 13C, and 95Mo n.m.r. spectra in solution.

A quindecanuclear nickel–sulphur cluster compound with triphenylphosphine, Ni15(µ3-S)6(µ4-S)9(PPh3)6, is obtained from the reaction of NiCl2, PPh3, and Na2S in dimethylformamide–tetrahydrofuran and has been shown by X-ray single crystal structural analysis to be co-facial quater-octahedra in a chain.

The cluster compound [(η5-Cp)4CO4(η4-S)2] was isolated from the reaction between [(η5-Cp)Co(PR3)2] and Li2S at 60 ·C; the tetramer is capped by two quadruply-bridging sulphur atoms above and below the Co4 square plane to form a distorted octahedral core Co4S2 as shown by X-ray single crystal structural analysis.

The reactions of Ni2+, edt2– and PR3(R = Ph or Et) in MeOH gave the complexes [Ni(tpdt)(PPh3)]1, [Ni2(edt)2(PPh3)2]2, [Ni2(edt)2(Pet3)2]3 and [Ni2(tpdt)2]4(edt = ethane-1,2-dithiolate, tpdt = 3-thiapentane-1,5-dithiolate). Complex 3 is orthorhombic and crystallizes in space group Pbca with a= 14.086(4), b= 25.569(11), c= 13.768(4)A, Z= 8, R= 0.060. Complex 4 also crystallizes in the orthorhombic space group Pbca with a= 10.935(8), b= 28.826(15), c= 9.437(4)A, Z= 8, R= 0.047. All the nickel atoms are four-co-ordinated with distorted square-planar geometies of phosphorus and/or sulfur atoms. In the reaction system condensation of edt2– occurs through a C–S bond disruption to form tpdt2–, which co-ordinates to the nickel atoms to give complexes 1 and 4.

The complexes [Co(dppp)(SPh)2][dppp = 1,3-bis(diphenylphosphino)propane] and [Co(bdpp)(SPh)2][bdpp = bis(2-diphenylphosphinoethyl)phenylphosphine] were prepared in good yields by treating Co(dppp)Cl2 with NaSPh and elemental selenium in dimethylformamide and by treating CoCl2·6H2O and bdpp in acetonitrile with NaSPh, respectively. The complex [Co(dppp)(SPh)2] crystallizes in the triclinic space group P, with a= 9.665(2), b= 10.075(1), c= 18.288(2)A, α= 102.41(1), β= 93.89(1), γ= 92.40(1)° and Z= 2, whereas the complex [Co(bdpp)(SPh)2] is monoclinic, space group Cc, with a= 16.374(2), b= 26.033(3), c= 10.873(5)A, β= 117.49(2)° and Z= 4.

The complex [Co3(bdt)3(PBun3)3]1(H2bdt = benzene-1,2-dithiol) was obtained by the reaction of CoCl2, Na2bdt and PBun3 in 1:1:2 molar ratio in methanol. It crystallizes in triclinic space group P with a= 13.694(4), b= 18.460(4), c= 13.656(4)A, α= 100.69(2), β= 108.68(2), γ= 85.06(2)°, Z= 2, from 6366 reflections with I > 3σ(I), final R(R′)= 0.059 (0.066). The Co3 atoms form an isosceles triangle with rather short Co-Co bonds. The bdt ligands either bridge between two Co atoms or strongly chelate terminally to one Co atom and simultaneously bridge weakly to the others. Restricted air oxidation of 1 results in the isolation of [PHBun3][Co(bdt)2(PBun3)]2, which crystallizes in triclinic space group P with a= 10.800(3), b= 13.533(4), c= 15.342(2)A, α= 96.37(2), β= 108.57(2), γ= 97.02(2)°, Z= 2, from 3801 reflections with I > 3σ(I), R(R′)= 0.086 (0.088). The Co atom is in a square-pyramidal co-ordination environment with P in the axial position. The PBun3 group dissociates easily in dimethyl sulphoxide yielding paramagnetic [Co(bdt)2]–3 with square-planar cobalt co-ordination. Proton NMR data are discussed and cyclic voltammetry data reported.

An asymmetrical dinuclear cobalt complex Co2(dppe)(µ-SPh)3SPh (dppe = Ph2PCH2CH2PPh2) has been prepared and characterized by X-ray diffraction showing the entirely different geometrical environments of the two cobalt(II) atoms.