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The novel cyclic ligand 1-phenyl-1-phospha-4-7-dithiacyclononane forms highly stable transition metal and d10 metal complexes; the X-ray structure of the tetrahedral copper(I) complex shows the ligand to be capable of both facial tridentate coordination and monodentate coordination, and the nickel(II) complex is easily and reversibly converted electrochemically to nickel(I) and nickel(III) complexes.

[MoBr 2 (CO) 4 ] reacts with 2,4,6-Pr i 3 C 6 H 2 S − (TIPT − ) to give trigonal bipyramidal [Mo(CO) 2 (TIPT) 3 ] − ( I ). The tungsten and rhenium analogues are isostructural. Complex I reacts with neutral donors to give [Mo(TIPT) 3 (CO)L] − (L = MeCN, Bu t CN, MeNC, Bu t NC or PMe 2 Ph) and with [PhN 2 ][BF 4 ] to give [Mo(N 2 Ph)(TIPT) 3 (MeCN)] ( II ). Complex II is also trigonal bipyramidal with axial N 2 Ph and MeCN ligands. [MoCl 3 (MeCN) 3 ] reacts with TIPT in MeCN to give “[Mo(MeCN)(TIPT) 4 ]”. By contrast, MoCl 4 in dimethoxyethane with TIPT gives [Mo 2 (TIPT) 6 ] together with [MoO(TIPT) 4 ] − . An X-ray crystal structure of [Mo 2 (TIPT) 6 ] revealed an Mo-Mo triple bond analogous to [Mo 2 (OR) 6 ] species. The phenylated thiol, 2,6-Ph 2 C 6 H 3 S − ), reacts with [MoBr 2 (CO) 4 ] in dimethoxyethane to give [Mo(CO)(DPT) 2 ]. One of the o -phenyl groups is η 6 -bonded to give a distorted piano-stool structure. The η 6 -phenyl group is readily displaced by a range of neutral donor ligands to give access to a new series of Mo(II) thiolato-derivatives.

Reaction of [ReCl2(OMe)(NO)(PPh3)2] with a range of thiophenols under basic conditions gives one of two classes of products depending on the steric requirements of the thiols. A representative member of each class has been characterised by an X- ray crystal structure determination. Thiophenols with methyl or isopropyl groups in their ortho positions give the mononuclear complexes [Re(SR)4(NO)](SR = SC6H2Pri3-2,4,6, SC6H3Pri2-2,6, SC6H2Pri2-2,6-4- Br, or SC6H2Me3-2,4,6) which are trigonal bipyramidal with an axial NO group. Thiophenols without ortho-substituents give the dinuclear anions [Re2(SR)7(NO)2]–(SR = SPh or SC6H4Me-4) which contain a triple thiolate bridge between two equivalent rhenium atoms. These anions show a fluxionality involving intramolecular exchange of six thiolato-ligands.

A. Introduction B. Complexes with terminal thiolato-ligands (i) Mononuclear homoleptic complexes with monoand bi-dentate thiolates _ (ii) Mononuclear complexes with heteroligands (a) Oxo-complexes (b) Complexes with metal-nitrogen multiple bonds (c) Miscellaneous monomeric thiolato complexes with other heteroligands . (iii) Complexes with sterically hindered thiolato-ligands (a) Chromium, molybdenum and tungsten (b) Manganese, technetium and rhenium (c) Iron, ruthenium and osmium. (d) Cobalt, rhodium and iridium. (e) Copper, silver and gold C. Complexes with CL’-bridging thiolato-ligands (i) Introduction (ii) Dinuclear and linear polynuclear complexes with two p2-thiolato-ligands . . (a) Molybdenum ..... (b) Manganese, technetium and rhenium (c) Iron (d) Cobalt (e) Nickel, palladium and platinum (f) Copper, silver and gold. (g) Zinc, cadmium and mercury (iii) Complexes with three Ir_2-thiolato-ligands (iv) Complexes with quadruple r2-thiolato-ligands (v) Three-dimensional clusters (a) Clusters with tetrahedral metal centres (b) Copper and silver (c) Nickel, palladium and platinum (d) Other cluster types D. Complexes with p’-bridging thiolato-ligands E. Synthesis of thiolato-complexes . .

The human sodium/iodide symporter (hNIS) is a well-established target in thyroid disease and reporter gene imaging using gamma emitters (123)I-iodide, (131)I-iodide and (99m)Tc-pertechnetate. However, no PET imaging agent is routinely available. The aim of this study was to prepare and evaluate (18)F-labelled tetrafluoroborate ([(18)F]TFB) for PET imaging of hNIS.[(18)F]TFB was prepared by isotopic exchange of BF (4) (-) with [(18)F]fluoride in hot hydrochloric acid and purified using an alumina column. Its identity, purity and stability in serum were determined by HPLC, thin-layer chromatography (TLC) and mass spectrometry. Its interaction with NIS was assessed in vitro using FRTL-5 rat thyroid cells, with and without stimulation by thyroid-stimulating hormone (TSH), in the presence and absence of perchlorate. Biodistribution and PET imaging studies were performed using BALB/c mice, with and without perchlorate inhibition.[(18)F]TFB was readily prepared with specific activity of 10 GBq/mg. It showed rapid accumulation in FRTL-5 cells that was stimulated by TSH and inhibited by perchlorate, and rapid specific accumulation in vivo in thyroid (SUV = 72 after 1 h) and stomach that was inhibited 95% by perchlorate.[(18)F]TFB is an easily prepared PET imaging agent for rodent NIS and should be evaluated for hNIS PET imaging in humans.

A series of metal-chelating lipid conjugates has been designed and synthesized. Each member of the series bears a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) macrocycle attached to the lipid head group, using short n-ethylene glycol (n-EG) spacers of varying length. Liposomes incorporating these lipids, chelated to Gd(3+), (64)Cu(2+), or (111)In(3+), and also incorporating fluorescent lipids, have been prepared, and their application in optical, magnetic resonance (MR) and single-photon emission tomography (SPECT) imaging of cellular uptake and distribution investigated in vitro and in vivo. We have shown that these multimodal liposomes can be used as functional MR contrast agents as well as radionuclide tracers for SPECT, and that they can be optimized for each application. When shielded liposomes were formulated incorporating 50% of a lipid with a short n-EG spacer, to give nanoparticles with a shallow but even coverage of n-EG, they showed good cellular internalization in a range of tumour cells, compared to the limited cellular uptake of conventional shielded liposomes formulated with 7% 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[carboxy(polyethyleneglycol)(2000)] (DSPE-PEG2000). Moreover, by matching the depth of n-EG coverage to the length of the n-EG spacers of the DOTA lipids, we have shown that similar distributions and blood half lives to DSPE-PEG2000-stabilized liposomes can be achieved. The ability to tune the imaging properties and distribution of these liposomes allows for the future development of a flexible tri-modal imaging agent.

The Re(II) nitrosyl complex [ReCl2(OMe)(NO)(PPh3)2] reacts with excess 2,6-Pr2iC6H3S−(DIPT−) in methanol to give the Re(III) complex [Re(DIPT)4(NO)] (I) whereas thiophenolate gives a thiolatobridged Re(II) dimer. Crystal data for(I): crystallizes in the orthorhombic space group Pbca, a = 13.218(6) A, b = 19.534(9) A, c = 38.115(13) A, V = 9841.3(6) A3 to give Dcalc = 1.35 g cm−3 for Z = 8. Structure solution and refinement are based on 3047 reflections with Io>3σ|Io| and yielded a final R value of 0.064. The overall geometry about Re is trigonal bipyramidal with an apical NO group with a nearly linear ReNO system (ReNO, 173.6(14)°). The polymeric species ‘{Mo(NO)(NH2O)}n’ reacts with excess 2,4,6-Pr3iC6H2S−(TIPT− to give[Mo(TIPT)3(NH3)(NO)]·C5H12 (II) (C5H12 = n-pentane) whereas thiophenolate anion gives [Mo(SPh)4(NO)]−. Crystal data for (II): space group P21/n with a = 10.477(3) A, b = 26.359(5) A, c = 20.124(4) A, β = 87.21(1)°, with V = 5550.9(12) A3 to give Dcalc = 1.05 g cm−3 for Z = 4. Structure refinement was based on 1040 reflections with Io>3σ|Io| and yielded a final R value of 0.079. The geometry about Mo is again trigonal bipyramidal with apical NO and NH3 groups and again an essentially linear MoNO system (MNO = 174.2(3)°).

A. Introduction B. Complexes with terminal thiolato-ligands (i) Mononuclear homoleptic complexes with monoand bi-dentate thiolates _ (ii) Mononuclear complexes with heteroligands (a) Oxo-complexes (b) Complexes with metal-nitrogen multiple bonds (c) Miscellaneous monomeric thiolato complexes with other heteroligands . (iii) Complexes with sterically hindered thiolato-ligands (a) Chromium, molybdenum and tungsten (b) Manganese, technetium and rhenium (c) Iron, ruthenium and osmium. (d) Cobalt, rhodium and iridium. (e) Copper, silver and gold C. Complexes with CL’-bridging thiolato-ligands (i) Introduction (ii) Dinuclear and linear polynuclear complexes with two p2-thiolato-ligands . . (a) Molybdenum ..... (b) Manganese, technetium and rhenium (c) Iron (d) Cobalt (e) Nickel, palladium and platinum (f) Copper, silver and gold. (g) Zinc, cadmium and mercury (iii) Complexes with three Ir_2-thiolato-ligands (iv) Complexes with quadruple r2-thiolato-ligands (v) Three-dimensional clusters (a) Clusters with tetrahedral metal centres (b) Copper and silver (c) Nickel, palladium and platinum (d) Other cluster types D. Complexes with p’-bridging thiolato-ligands E. Synthesis of thiolato-complexes . .

The coordination chemistry of the three crown thioethers 1,4,7-trithiacyclononane (9S3), 1,5,9-trithiacyclododecane (12S3), and 1,4,7,10,13,16-hexathiacyclooctadecane (18S6) with Ag(I) has been investigated by structural and electrochemical methods. The bis complex (Ag(9S3){sub 2})(CF{sub 3}SO{sub 3}) contains a six-coordinate Ag(I) ion with Ag-S distances ranging from 2.696 (2) to 2.753 (1) {angstrom}. Chemical or electrochemical oxidation yields (Ag(9S3){sub 2}){sup 2+}, which has been studied by optical and EPR methods. The halide adducts (Ag(9S3)Cl) and (Ag(18S6)Br) both contain a tetrahedral AgS{sub 3}X core. In the former case, 9S3 coordinates in a tridentate fashion to yield a discrete, monomeric complex. In the latter, 18S6 provides two thioethers to one Ag(I) and a third to another to yield a polymeric chain. In (Ag(12S3))(CF{sub 3}SO{sub 3}) {center dot} MeCN, each Ag(I) ion coordinates to three thioether groups (one from each of three independent 12S3 molecules) as well as a CF{sub 3}SO{sub 3}{sup {minus}} counterion to yield distorted-tetrahedral geometry. In turn, the three ligand S atoms coordinate to different Ag(I) ions to generate a network structure. These results highlight the profound influence of ligand conformation on the structure and solution chemistry of their complexes. Crystal data for (Ag(9S3){sub 2}) (CF{sub 3}SO{sub 3}), (Ag(18S6)Br), (Ag(9S3)Cl), and (Ag(12S3))(CF{sub 3}SO{sub 3}) {centermore » dot} MeCN are reported.« less

The complexes [PPh4][ReO(SCH2CH2S)2](1), [NMe4][ReS(SCH2CH2S)2](3), and [PPh4][Re{(SCH2)3CCH3}2](5) have been synthesised by the reactions of K2[ReCl6] or [ReOCl3(PPh3)2] with the respective polythiol in the presence of triethylamine in methanol solution. Complex (1) crystallises in space group Pcab with a= 15.122(3), b= 18.685(4), c= 19.648(4)A, U= 5 542.02 A3, and Z= 4. Structure solution based on 2 072 independent reflections was refined to R= 0.063. Complex (3) crystallises in space group P21/c with a= 9.539(3), b= 15.123(4), c= 21.815(4)A, β= 93.58(1)°, U= 3 140.9 A3, and Z= 8. Structure solution based on 3 329 independent reflections was refined to R= 0.029. Complex (5) crystallises in space group P21/n with a= 11.506(3), b= 17.096(4), c= 18.115(4)A, β= 102.32(1)°, U= 3 488.9 A3, and Z= 4. Structure solution based on 2 380 independent reflections was refined to R= 0.0517. The [ReS(SCH2CH2S)2]– and [ReO(SCH2CH2S)2]– anions exhibit square pyramidal geometry with a terminal sulphido or oxo ligand in the apical position. The S2– ligand is derived from decomposition of the 1,2-ethanedithiolate anion with elimination of ethylene. The [Re{(SCH2)3CCH3}2]– anion has a six-co-ordinate Re atom in a trigonal prismatic co-ordination sphere. The factors responsible for the adoption of the trigonal prismatic structure are discussed.

Supplemental Digital Content is available in the text., Background and objectives Nuclear medicine contributes greatly to the clinical management of patients and experimental medicine. This report aims to (1) outline the current landscape of nuclear medicine research in the UK, including current facilities and recent or ongoing clinical studies and (2) provide information about the available pathways for clinical adoption and NHS funding (commissioning) of radiopharmaceuticals. Methods Evidence was obtained through database searches for UK-based nuclear medicine clinical studies and by conducting a questionnaire-based survey of UK radiopharmaceutical production facilities. A recent history of clinical commissioning, either through recommendations from the National Institute for Health and Care Excellence (NICE) or through NHS specialised services commissioning, was compiled from publicly available documents and policies. Results The collected data highlighted the UK’s active nuclear medicine research community and recent investment in new facilities and upgrades. All commissioning routes favour radiopharmaceuticals that have marketing authorisation and since 2017 there has been a requirement to demonstrate both clinical and cost-effectiveness. Whilst radiopharmaceuticals for molecular radiotherapy are well suited to these commissioning pathways, diagnostic radiotracers have not historically been assessed in this manner. Conclusions We hope that by collating this information we will provide stimulus for future discussion and consensus statements around this topic.

Myocardial hypoxia is a major factor in the pathology of cardiac ischemia and myocardial infarction. Hypoxia also occurs in microvascular disease and cardiac hypertrophy, and is thought to be a prime determinant of the progression to heart failure, as well as the driving force for compensatory angiogenesis. The non-invasive delineation and quantification of hypoxia in cardiac tissue therefore has the potential to be an invaluable experimental, diagnostic and prognostic biomarker for applications in cardiology. However, at this time there are no validated methodologies sufficiently sensitive or reliable for clinical use. PET imaging provides real-time spatial information on the biodistribution of injected radiolabeled tracer molecules. Its inherent high sensitivity allows quantitative imaging of these tracers, even when injected at sub-pharmacological (≥pM) concentrations, allowing the non-invasive investigation of biological systems without perturbing them. PET is therefore an attractive approach for the delineation and quantification of cardiac hypoxia and ischemia. In this review we discuss the key concepts which must be considered when imaging hypoxia in the heart. We summarize the PET tracers which are currently available, and we look forward to the next generation of hypoxia-specific PET imaging agents currently being developed. We describe their potential advantages and shortcomings compared to existing imaging approaches, and what is needed in terms of validation and characterization before these agents can be exploited clinically.

The chelating diphosphine 2,3-bis(diphenylphosphino)maleic anhydride (L 1 ) reacted with CuCl to give [CuClL 1 2 ] 1a in which the copper is bound to three phosphorus atoms and one chlorine in a pseudo-tetrahedral structure, as demonstrated by X-ray crystallography. Compound L 1 reacted with [Cu(MeCN) 4 ][PF 6 ] to give the red salt [CuL 1 2 ][PF 6 ] 1b in which the copper is bound by four phosphorus atoms of two chelating bidentate ligands, as demonstrated by X-ray crystallography. Addition of chloride ions to 1b quantitatively affords 1a. Complex 1a can be converted quantitatively into [CuL 1 2 ][NO 3 ] 1c by treatment with AgNO 3 . These complexes reacted quantitatively with water, benzylamine and methanol to give the corresponding [CuL 2 2 ] + 2, [CuL 3 2 ] + 3 and [CuL 4 2 ] + 4 where L 2 = 2,3-bis(diphenylphosphino)maleic acid and L 3 and L 4 are the monobenzylamide and monomethyl ester derivatives, respectively, of L 2 . Uncomplexed L 1 can also be hydrolysed to L 2 or derivatised with benzylamine or methanol to give L 3 and L 4 respectively. Compounds L 2 , L 3 and L 4 reacted with copper-(I) or -(II) salts to yield salts of 2, 3 and 4. This chemistry provides versatile routes to the synthesis of stable bioconjugates containing copper or radiocopper and of derivatised solids containing pendant diphosphine ligands.

99mTc-SnF2 colloid (Radpharm LLK) leucocyte labelling agent is used in whole blood, exploiting phagocytosis. The objectives of this work were to optimize leucocyte labelling in leucocyte-enriched plasma, and to investigate: (i) the effect of temperature and other factors on labelling efficiency; (ii) the selectivity for different leucocyte types; (iii) the viability of the labelled cells and efflux of the radiolabel; and (iv) the physical characteristics of the colloid. Density gradient centrifugation was used to investigate the labelling efficiency, cell selectivity and efflux, Trypan blue to study the viability, and laser scattering, electron microscopy and membrane filtration to investigate particle size and morphology. Particles appeared as loose, coiled, chain-like aggregates of much smaller particles (0.05 microm). The aggregate diameter ranged from0.1 to5 microm and increased with time. The distribution of radioactivity amongst the particle sizes varied widely. The labelling efficiency in leucocyte-rich plasma was enhanced at 37 degrees C compared to room temperature, and by centrifuging during labelling. The selectivity for different leucocyte types varied markedly between batches and blood samples, in some cases showing preference for mononuclear cells and in others for granulocytes. Viability was excellent and comparable with 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO)-labelled cells. A significant fraction of radiolabel, comparable to that observed with 99mTc-HMPAO, was lost from leucocytes during incubation in vitro over 4 h. Thus, 99mTc-SnF2 is a convenient, efficient labelling agent for leucocytes, but shows variable cell selectivity which may be linked to particle size variability, and there is significant efflux of radioactivity from labelled cells.

The greater lability of Co(II) relative to Co(III) can potentially be used to achieve selective delivery of nitrogen mustard type molecules to hypoxic cells. Attempts to improve the stability of the Co(II) state by utilising tripodal tetradentate ligands are described, together with the results of DF calculations. Rhenium has two β-emitting isotopes 186 Re and 188 Re that have potential for use to treat cancer if the complexes can be targeted with sufficient specificity. We describe some new rapid low temperature routes using hydrazines to labile Re(V) and Re(III) species which provide potential convenient access to a wide range of oxo- and diazenido-complexes. The synthesis of new Re(V) and Re(III) thiosemicarbazone complexes is presented in the context of obtaining hypoxic selective species. Copper(II) bis(thiosemicarbazone) complexes are known to be hypoxic selective and spectroscopic, cyclic voltammetric and computational studies of the mechanism are presented, together with the synthesis of new Cu(II) complexes directed towards the hypoxic selective delivery of nitrogen mustard type molecules.

Background The trapping mechanisms of the PET hypoxia imaging agent copper(II)-diacetyl-bis(N 4-methylthiosemicarbazone) (64Cu(ATSM)) remain unresolved, although its reduction prior to dissociation may be mediated by intracellular thiols. Glutathione (GSH) is the most abundant intracellular thiol, and its redox status changes in cancer cells and ischaemic myocardium (two prime applications for 64Cu(ATSM) PET). We therefore investigated whether modification of intracellular GSH content affects the hypoxia selectivity of 64Cu(ATSM). Methods Isolated rat hearts (n = five per group) were perfused with aerobic buffer (equilibrated with 95%O2/5%CO2) for 15 min, then hypoxic buffer (95%N2/5%CO2) for 20 min. Cardiac glutathione was depleted by buthionine sulphoximine (BSO, 4 mmol/kg/ 48 h intraperitoneal), or augmented by N-acetyl cysteine (NAC, 4 mmol/L) in the perfusion buffer. Cardiac 64Cu retention from three 2-MBq bolus injections of 64Cu(ATSM) before and during hypoxia was then monitored by NaI detectors. Results Cardiac GSH content was elevated by NAC and depleted by BSO (from 7.9 ± 2.0 to 59.3 ± 8.3 nmol/mg and 3.7 ± 1.0 nmol/mg protein, respectively; p p Conclusion Modification of GSH levels had no impact upon the pharmacokinetics or hypoxia selectivity of 64Cu(ATSM). While thiols may yet prove essential for the intracellular trapping of 64Cu(ATSM), they are not the determinants of its hypoxia selectivity.

The treatment of painful skeletal metastases is a common clinical problem, and the use of therapeutic radionuclides which localize at metastatic sites has been found to be an effective method for treatment of pain, especially for multiple sites for which the use of external beam irradiation is impractical. There are currently several metastatic-targeted agents radiolabeled with various therapeutic radionuclides which are in various stages of clinical investigation. Since neutron-rich radionuclides are produced in research reactors and often decay by emission of β− particles, most radionuclides used for bone pain palliation are reactor-produced. Key examples of radionuclides produced by single neutron capture of enriched targets include rhenium-186 and samarium-153. In addition, generator systems are also of interest which provide therapeutic daughter radionuclides from the decay of reactor-produced parent radionuclides. One important example is rhenium-188, available from generators via decay of reactor-produced tungsten-188. Tin-117m is an example of a reactor-produced radionuclide which decays with the emission of low-energy conversion electrons rather than by β− decay. Each of these agents and/or radionuclides has specific advantages and disadvantages, however, the ideal agent for bone pain palliation has not yet been identified. The goal of this paper is to briefly review the production and use of several reactor-produced radionuclides for bone pain palliation, and to discuss the role of the ORNL High Flux Isotope Reactor (HFIR) for the production of many of these radionuclides.

Molecular imaging and radiotherapy using radionuclides is a rapidly expanding field of medicine and medical research. This article highlights the development of the role of inorganic chemistry in designing and producing the radiopharmaceuticals on which this interdisciplinary science depends.

Synthese a partir de dichloro-1,2 ethane et de thio-2,2' bis-ethanethiol en presence de carbonate de cesium dans le DMF

Complex [Cu2(9S3)3]2+ contains two {Cu(l)(9S3)} units bond to a third, exodentate 9S3, in the first example of monodentate co-ordination by this ligand.

[ReOCl3(PPh3)2] reacts with two equivalents of Ph2PCH2CH2SH in tetrahydrofuran to give [ReOCl(Ph2PCH2CH2S)2]. An excess of tridentate PhP(CH2CH2SH)2 reacts with [ReOCl3(PPh3)2] to yield [Re{PhP(CH2CH2S)2}{PhP(CH2CH2S)(CH2CH2SH)}] containing a pendant unto-ordinated SH group. This complex reacts reversibly with CO to form [Re{PhP(CH2CH2S}{PhP(CH2-CH2S)(CH2CH2SH)}(CO)][ν(CO) at 1 980 Cm–1]. The MIV complexes [MCl4L2][M = MO or W, L = PPh3 or MeCN) react with PhP(CH2CH2SH)2 in MeOH to give [M(PhP(CH2CH2S)2)2]. An X-ray crystal-structure determination for the complex with M = MO showed a distorted octahedral structure with an average MO–S distance of 2.44 A. The complex crystallises in the triclinic space group p, with a= 10.601(7), b= 10.867(4), c= 12.347(1)A, α= 66.98(3), β= 85.60(4), γ= 63.70(4)°, and Z= 2. 1 337 Unique reflections with I0 3σ(I0) used in the solution converged at R= 0.0979. The hydrazido(2–) complexes [MCl(NNMe2)2(PPh2)2]Cl react with PhP(CH2CH2SH)2 in MeOH to give [M(NNMe2){PhP(CH2CH2S)2}2](M = MO or W). An X-ray crystal-structure determination of the complex with M = MO revealed a distorted pentagonal-bipyramidal structure with a linear apical NNMe2 ligand. The complex crystallises in the monoclinic space group P21/n, with a= 11.349(2), b= 12.403(3), c= 19.302(4)A, β= 104.28(2)°, and Z= 4. 2 796 Unique reflections with I0 > 3σ(I0) used in the solution converged at R= 0.605.

The complexes [PPh4][ReO(SCH2CH2S)2](1), [NMe4][ReS(SCH2CH2S)2](3), and [PPh4][Re{(SCH2)3CCH3}2](5) have been synthesised by the reactions of K2[ReCl6] or [ReOCl3(PPh3)2] with the respective polythiol in the presence of triethylamine in methanol solution. Complex (1) crystallises in space group Pcab with a= 15.122(3), b= 18.685(4), c= 19.648(4)A, U= 5 542.02 A3, and Z= 4. Structure solution based on 2 072 independent reflections was refined to R= 0.063. Complex (3) crystallises in space group P21/c with a= 9.539(3), b= 15.123(4), c= 21.815(4)A, β= 93.58(1)°, U= 3 140.9 A3, and Z= 8. Structure solution based on 3 329 independent reflections was refined to R= 0.029. Complex (5) crystallises in space group P21/n with a= 11.506(3), b= 17.096(4), c= 18.115(4)A, β= 102.32(1)°, U= 3 488.9 A3, and Z= 4. Structure solution based on 2 380 independent reflections was refined to R= 0.0517. The [ReS(SCH2CH2S)2]– and [ReO(SCH2CH2S)2]– anions exhibit square pyramidal geometry with a terminal sulphido or oxo ligand in the apical position. The S2– ligand is derived from decomposition of the 1,2-ethanedithiolate anion with elimination of ethylene. The [Re{(SCH2)3CCH3}2]– anion has a six-co-ordinate Re atom in a trigonal prismatic co-ordination sphere. The factors responsible for the adoption of the trigonal prismatic structure are discussed.

[MBr2(CO)4](M = MO or W) react with thiolate anions SR– to give the anions [M(SR)3(CO)2]–(SR = SC6H2Pri3-2,4,6, SC6H3Pri2-2,6, SC6H2Br-4-Pri2-2,6, SC6H2Me3–2,4,6, SC6F5). The complex [pph4][Mo(SC6H2Pri3-2,4,6)3(CO)2] crystallises in space group P with a= 13.451 (2), b= 14.229(2), c= 19.862(3)A, α= 96.11(1), β= 94.11(1), γ= 111.04(1)°, and Z= 2. Structure analysis based on 2 939 reflections with I0 3σ(I0) refined to R= 0.075. The NNPh and MeCN ligands occupy the axial sites of a trigonal bipyramid with the thiolates equatorial.

By the reaction of [ReNCl2(PR′3)n](PR′3= PPh3, n= 2; or PMe2Ph, n= 3) with the bulky thiol 2,4,6-tri-isopropylbenzenethiol (Htipt) under varying conditions, the nitrido-complexes [ReN(tipt)2(PR′3)2], Na2[ReN(tipt)4]·2thf (thf = tetrahydrofuran), and [PPh4][ReN(tipt)4] have been isolated. The last is a paramagnetic rhenium(VI) complex derived from the aerial oxidation of the rhenium(V) anion [ReN(tipt)4]2–. The arylimidorhenium(V) complexes [PPh4][Re(NR″)(tipt)4](R″= Ph, C6H4OMe-4, or C6H4Me-4) can be isolated by the reaction of [Re(NR″)Cl3(PPh3)2] with Htipt and triethylamine, whereas N2 loss occurs with PhS–. The complexes [Re(tipt)3(NCR‴)2](R‴= Me or But) have been prepared by reaction of K2[ReCL6] with Htipt and triethylamine in R‴CN as solvent. These bis(nitrile) complexes have a trigonal-bipyramidal structure with equatorial thiolate ligands. They react with CO to give, sequentially, two isomers of [Re(tipt)3(CO)(NCR‴)] and then [Re(tipt)3(CO)2] which have analogous structures. Analogues of some of the complexes, containing 2,4,6-trimethylbenzenethiolate or 2,6-di-isopropylbenzenethiolate ligands, are also described.

1,4,7-Trithiacyclononane (9S3) reacts with soluble silver(I) salts to form [Ag(9S3)2]+, a monomeric complex that has a distorted octahedral structure and is readily oxidised to the silver(II) complex.