Ag SO Research Articles

Silver-functionalized silica aerogel for iodine capture: Adsorbent aging by NO2 in spent nuclear fuel reprocessing off-gas

Silver-functionalized silica aerogel (Ag 0 -Aerogel) is considered a promising porous adsorbent for the capture of iodine from nuclear fuel reprocessing off-gas. The Ag 0 -Aerogel, nevertheless, experiences a steady loss of capacity when exposed to NO 2 in the off-gas. This phenomenon is known as aging and its governing processes remain unclear. We exposed Ag 0 -Aerogel samples to 2% NO 2 in dry air at 150 °C for up to 1 month, followed by I 2 loading. Samples were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy. Our results elucidated the precise Ag species in Ag 0 -Aerogel that adsorb I 2 : (i) Ag 0 nanoparticles, (ii) Ag thiolates (Ag–S-r) covering the nanoparticles and the aerogel backbone, and (iii) Ag–S complexes including amorphous Ag 2 S. We unraveled the two predominant underlying processes of aging in NO 2 : (i) Ag–S-r is oxidized by NO 2 forming silver sulfonate (Ag–SO 3 -r) which is oxidized further to silver sulfate (Ag 2 SO 4 ) molecules, (ii) Ag 2 SO 4 molecules then migrate from the pores to the aerogel surface and aggregate yielding Ag 2 SO 4 particles that do not adsorb I 2 . Plausible reaction pathways and aggregation mechanisms are explored. These findings may be used to guide the discovery of more advanced materials for iodine capture and the development of accurate predictive models. • The iodine capacity of Ag-aerogel is reduced by NO 2 at elevated temperatures. • Ag nanoparticles and Ag–S compounds coherently adsorb iodine. • NO 2 oxidizes Ag-thiolates forming Ag 2 SO 4 molecules that favor iodine adsorption. • Ag 2 SO 4 molecules migrate and accumulate on particles preventing iodine adsorption. • Thiolation step directly impacts Ag-aerogel aging in NO 2 .

Reconnaissance of reactivity of an Ag(ii)SO4 one-electron oxidizer towards naphthalene derivatives

Ag(ii)SO4 – a powerful oxidizer – allows for single-pot oxidative aromatic coupling of naphthalene and its 1- and 2-substituted derivatives.

Redetermination of crystal structure of Ag(ii)SO4and its high-pressure behavior up to 30 GPa

Here we redetermine the crystal structure of Ag(II)SO4, an unusual d9 system, at 1 atm from powder X-ray data and we report hydrostatic pressure X-ray diffraction experiments on Ag(II)SO4 inside the diamond anvil cell. AgSO4 crystallizes in the monoclinic C2/c cell, with a = 12.8476(2) A, b = 13.6690(4) A, c = 9.36678(19) A, β = 47.5653(13)°, and V = 1214.04(5) A3 (Z = 16). AgSO4 exhibits bulk modulus, B0, of 36.9 GPa, and undergoes sluggish decomposition at ∼23 GPa yielding a high-pressure phase of Ag2S2O7 (K2S2O7-type), with the substrate and product coexisting at 30 GPa. Theoretical calculations within Density Functional Theory for the C2/c cell nicely reproduce the observed trend for lattice constants as well as the B0 values of AgSO4, and suggest that the rigidity of the infinite [Ag(SO4)] chains as well as the Jahn–Teller effect for the Ag(II) cation persist even at 30 GPa.

Crystal and electronic structure, lattice dynamics and thermal properties of Ag(i)(SO3)R (R = F, CF3) Lewis acids in the solid state

Trifluoromethansulfonate of silver(I), AgSO(3)CF(3) (abbreviated AgOTf), extensively used in organic chemistry, and its fluorosulfate homologue, AgSO(3)F, have been structurally characterized for the first time. The crystal structures of both homologues differ substantially from each other. AgOTf crystallizes in a hexagonal system (R3 space group, No.148) with a = b = 5.312(3) Å and c = 32.66(2) Å, while AgSO(3)F crystallizes in a monoclinic system in the centrosymmetric P2(1)/m space group (No.11) with a = 5.4128(10) Å, b = 8.1739(14) Å, c = 7.5436(17) Å, and β = 94.599(18)°, adopting a unique structure type (100 K data). There are two types of fluorosulfate anions in the structure; in one type the F atom is engaged in chemical bonding to Ag(I) and in the other type the F atom is terminal; accordingly, two resonances are seen in the (19)F NMR spectrum of AgSO(3)F. Theoretical analysis of the electronic band structure and electronic density of states, as well as assignment of the mid- and far-infrared absorption and Raman scattering spectra for both compounds, have been performed based on the periodic DFT calculations. AgSO(3)F exhibits an unusually low melting temperature of 156 °C and anomalously low value of melting heat (ca. 1 kJ mol(-1)), which we associate with (i) disorder of its anionic sublattice and (ii) the presence of 2D sheets in the crystal structure, which are weakly bonded with each other via long Ag-O(F) contacts. AgSO(3)F decomposes thermally above 250 °C, yielding mostly Ag(2)SO(4) and liberating SO(2)F(2). AgOTf is much more thermally stable than AgSO(3)F; it undergoes two consecutive crystallographic phase transitions at 284 °C and 326 °C followed by melting at 383 °C; its thermal decomposition commences above 400 °C leading at 500 °C to crystalline Ag(2)SO(4) and an unidentified phase as major products of decomposition in the solid state.

Thermal and chemical decomposition of di(pyrazine)silver(ii) peroxydisulfate and unusual crystal structure of a Ag(i) by-product

High purity samples of a [Ag(pyrazine)(2)]S(2)O(8) complex were obtained using modified synthetic pathways. Di(pyrazine)silver(II) peroxydisulfate is sensitive to moisture forming [Ag(pyrazine)(2)](S(2)O(8))(H(2)O) hydrate which degrades over time yielding HSO(4)(-) derivatives and releasing oxygen. One polymorphic form of pyrazinium hydrogensulfate, β-(pyrazineH(+))(HSO(4)(-)), is found among the products of chemical decomposition together with unique [Ag(i)(pyrazine)](5)(H(2)O)(2)(HSO(4))(2)[H(SO(4))(2)]. Chemical degradation of [Ag(pyrazine)(2)]S(2)O(8) in the presence of trace amounts of moisture can explain the very low yield of wet synthesis (11-15%). Attempts have failed to obtain a mixed valence Ag(II)/Ag(I) pyrazine complex via partial chemical reduction of the [Ag(pyrazine)(2)]S(2)O(8) precursor with a variety of inorganic and organic reducing agents, or via controlled thermal decomposition. Thermal degradation of [Ag(pyrazine)(2)]S(2)O(8) containing occluded water proceeds at T > 90 °C via evolution of O(2); simultaneous release of pyrazine and SO(3) is observed during the next stages of thermal decomposition (120-285 °C), while Ag(2)SO(4) and Ag are obtained upon heating to 400-450 °C.

Variable coordination of a chiral diphosphine containing an amidinium/NHC group within its backbone: μ-P,P′, κ2-P,P′ and κ3-P,C,P′ coordination modes

A diphosphine ligand (1·HPF(6)), which is a potential precursor to a PC(NHC)P pincer, with a backbone containing two phenylene groups and a central bicyclic 4-aza-2-azoniabicyclo[3.2.1]oct-2-ene unit has been synthesised and coordinated to Pd(II) and Pt(II) to give trans-[M(κ(2)-P,P'-)Cl(2)]PF(6) where M = Pd (2) or Pt (3a). Single-crystal structure determinations of 2 and 3a show the complexes to be isostructural with the diphosphine coordinated in a trans-spanning fashion and the amidinium unit being protonated and non-coordinated. 2 and 3a react with CH(3)I to give the dimers trans-[Pd(2)(μ-1·H)(2)I(4)](PF(6))(2), 6, and trans-[Pt(2)(μ-1·H)(2)I(4)](PF(6))(2), 7, as the major products. This bridging mode of coordination of [1·H](+) is also seen in trans-[Rh(2)(μ-1·H)(1,5-COD)(2)Cl(2)]PF(6), 4, and [Pt(2)(μ-κ(2)-1·H)(dvdms)]PF(6), 5. Upon treatment with KO(t)Bu complexes and undergo deprotonation at the amidinium carbon to give trans-[M(κ(3)-P,C,P'-1)Cl]PF(6) where M = Pd (8), and Pt (9). The related trans-[Rh(κ(3)-P,C,P'-1)(CO)]PF(6) (10) is prepared directly from 1·HPF(6) and Rh(acac)(CO)(2): this and the palladium and platinum complexes 8 and 9 are isolated as isomeric mixtures as a consequence of a conformational isomerism. In situ deprotonation of 1·HPF(6) followed by addition of Ag(CF(3)SO(3)) gave S(Ag)-[Ag(κ(3)-P,C,P'-1)(CF(3)SO(3))], 11. Some preliminary studies of the reactivity of 2 and 8 in Suzuki-type reactions are reported and the Pt(0) system has been shown to be an active hydrosilylation catalyst.

Phonon spectra and phonon-dependent properties of AgSO 4, an unusual sulfate of divalent silver

Phonon spectra of recently synthesized Ag(II)SO 4 have been measured using infrared absorption and Raman scattering spectroscopy, and theoretically predicted using density functional theory calculations. Excellent agreement between experimental and theoretical results with correlation coefficient of 1.05 allowed for full assignment of the experimentally observed vibrational bands, as well as calculation of standard vibrational entropy of AgSO 4 (118.2 J mol −1 K −1), vibrational heat capacity at constant volume (99.1 J mol −1 K −1), zero-point energy (48.3 kJ mol −1). The experimental cut-off frequency of the phonon spectrum equals 1116 cm −1 which translates to the Debye temperature of 1606 K. High frequencies of S–O stretching modes render sulfate connections of Ag(II) attractive precursors of high-T C superconductors.

Crystal and electronic structures and high-pressure behavior of AgSO4, a unique narrow band gap antiferromagnetic semiconductor: LDA(+U) picture

We demonstrate that DFT calculations performed with the local density approximation (LDA) allow for significantly better reproduction of lattice constants, the unit cell volume and the density of Ag(II)SO(4) than those done with generalized gradient approximation (GGA). The LDA+U scheme, which accounts for electronic correlation effects, enables the accurate prediction of the magnetic superexchange constant of this strongly correlated material and its band gap at the Fermi level. The character of the band gap places the compound on the borderline between a Mott insulator and a charge transfer insulator. The size of the band gap (0.82 eV) indicates that AgSO(4) is a ferrimagnetic semiconductor, and possibly an attractive material for spintronics. A bulk modulus of 27.0 GPa and a compressibility of 0.037 GPa(-1) were determined for AgSO(4) from the third-order Birch-Murnaghan isothermal equation of state up to 20 GPa. Several polymorphic types compete with the ambient pressure P-1 phase as the external pressure is increased. The P-1 phase is predicted to resist pressure-induced metallization up to at least 20 GPa.

Photosensitive azobispyridine gold(i) and silver(i) complexes

The neutral and cationic dinuclear gold(I) compounds [(μ-N-N)(AuR)(2)] (N-N = 2,2'-azobispyridine (2-abpy), 4,4'-azobispyridine (4-abpy); R = C(6)F(5), C(6)F(4)OC(12)H(25)-p, C(6)F(4)OCH(2)C(6)H(4)OC(12)H(25)-p) and [(μ-N-N){Au(PR(3))}(2)](CF(3)SO(3))(2) (N-N = 2-abpy, 4-abpy, R = Ph, Me) have been obtained by displacement of a weakly coordinated ligand by an azobispyridine ligand. The corresponding silver(I) dinuclear [(μ-2-abpy){Ag(CF(3)SO(3))(PPh(3))}(2)] and polynuclear [{Ag(CF(3)SO(3))(4-abpy)}(n)] compounds have been obtained. The molecular structures of [(μ-2-abpy){Au(PPh(3))}(2)](CF(3)SO(3))(2) and [(μ-4-abpy){Au(PMe(3))}(2)](CF(3)SO(3))(2) have been confirmed by X-ray diffraction studies and feature linear gold(I) centers coordinated by pyridyl groups, and non-coordinated azo groups. In contrast the X-ray structure of [(2-abpy){Ag(CF(3)SO(3))(PPh(3))}(2)] shows tetracoordinated silver(I) centers involving chelating N-N coordination by pyridyl and azo nitrogen atoms. The gold(I) compounds with a long alkoxy chain do not behave as liquid crystals, and decompose before their melting point. The soluble gold(I) derivatives are photosensitive in solution and isomerize to the cis azo isomer under UV irradiation, returning photochemically or thermally to the most stable initial trans isomer. The silver(I) derivative [(2-abpy){Ag(CF(3)SO(3))(PPh(3))}(2)] also photoisomerizes in solution under UV irradiation, showing that its solid state structure, which would block isomerization by azo coordination, is easily broken. These processes have been monitored by UV-vis absorption and (1)H NMR spectroscopy. All these compounds are non-emissive in the solid state, even at 77 K.

Ag(I) Organometallic Coordination Polymers and Capsule with Tris-Allyl Cyclotriveratrylene Derivatives

Tris-allyl-cyclotriguaiacylene combines with silver salts to give a range of crystalline network structures and one discrete complex. A number of different coordination modes are found within the complexes including η(2)-allyl, aryl, and OR groups binding to Ag(I). AgSbF(6) gives two types of three-dimensional (3-D) coordination polymer with unusual topologies, along with a discrete Ag(2)L(2) capsule dependent on reaction stoichiometry and reaction conditions. Isostructural coordination chain structures are found with AgBF(4) and AgClO(4), while use of Ag(CF(3)SO(3)) gives two-dimensional (2-D) and 3-D coordination polymers through bridging triflate anions.

Aqua(trifluoromethanesulfonato)bis(1,3,7-trimethylpurine-2,6-dione)silver(I)

In the title compound, [Ag(CF3SO3)(C8H10N4O2)2(H2O)], the AgI atom is coordinated by two caffeine N atoms and, at longer distances, two O atoms of a coordinated water mol­ecule and the trifluoro­methane­sulfonate anion, resulting in an AgN2O2 seesaw geometry. The caffeine mol­ecules are roughly coplanar [dihedral angle = 5.81 (5)°]. In the crystal, mol­ecules self-assemble into a linear supra­molecular chain along the c axis via O—H⋯O hydrogen bonds involving the coordinated water moledcule and carbonyl O atoms. The packing is consolidated by weak C—H⋯O inter­actions.

The Theoretical Quest for Sulfate of Ag2+: Genuine Ag(II)SO4, Diamagnetic Ag(I)2S2O8, or Rather Mixed-Valence Ag(I)[Ag(III)(SO4)2

In an attempt to extend the chemistry of Ag(II) compounds to novel ligand environments, we have examined various polymorphs of an as yet unknown compound of AgSO(4) stoichiometry by means of a quantum chemistry DFT approach. Since AgSO(4) has not yet been prepared, we were interested whether genuine divalent silver, Ag(II), could be stabilized in the presence of sulfate (SO(4)(2-)) anions or whether it would rather have a tendency toward disproportionation to Ag(I)/Ag(III) (as known from binary oxide, "AgO") or maybe toward the formation of peroxodisulfate (S(2)O(8)(2-)) of Ag(I). Considering all important electromeric forms, Ag(II)SO(4), Ag(I)Ag(III)(SO(4))(2), and Ag(I)(2)S(2)O(8), in a variety of crystal structures, we examined their dynamical (vibrational) stability and discussed the most stable phases from the point of view of structural features thought to be crucial for appearance of high-T(C) superconductivity. We show that a compound of a nominal stoichiometry, AgSO(4), should most likely be a genuine paramagnetic sulfate of divalent silver which forms 3D ...Ag-O-S(O(2))-O... networks, and--unlike CuSO(4)--shows no direct connections of paramagnetic Ag(II) centers via Ag-O bridges. This must lead to low electronic dimensionality and concomitant low potential for the appearance of high-T(C) superconductivity. Finally, we discuss structural features of the most stable phase of AgSO(4) predicted here in a broader context of crystal structures of group 11 metals.

Novel complexes of silver(i) sulfate with 1-methylimidazole-2-thione: structures and vibrational spectroscopy

Crystallization of silver(I) sulfate with the ligand 1-methylimidazole-2-thione ('Hmimt') from aqueous solution, instead of yielding the expected 1:6 Ag(2)SO(4):Hmimt complex analogous to numerous other Ag(2)SO(4):thiourea-based ligand (1:6) complexes, has resulted in novel polymeric forms, one of unusual stoichiometry. Ag(2)SO(4):Hmimt (1:4) (x H(2)O) is of the form [...(mu-Hmimt)(2)Ag(mu-Hmimt)(2)Ag...](infinity|infinity)(SO(4)), with a one-dimensional polymeric cation. Ag(2)SO(4):Hmimt (3:8) (x 9 1/2 H(2)O) is a polymeric sheet structure containing Ag(12)(SO(4))(6)(Hmimt)(15) kernels linked by Hmimt ligands. The IR spectra of these compounds show unusually large shifts of the nu(NH) band due to the presence of N-H...O hydrogen bonding involving the N-H group of the ligand and the sulfate oxygen atoms. The complexes were also readily prepared by the solvent-assisted mechanochemical method, and the utility of this method for the preparation of deuterium-exchanged products for assistance in the assignment of the IR spectra is illustrated.

Organobismuth compounds with the pincer ligand 2,6-(Me2NCH2)2C6H3: Monoorganobismuth(iii) carbonate, sulfate, nitrate, and a diorganobismuthenium(iii) salt

The reaction of RBiCl(2) (1) [R = 2,6-(Me(2)NCH(2))(2)C(6)H(3)] with Na(2)CO(3) or Ag(2)SO(4) (1 : 1 molar ratio) gave RBiCO(3) (2) and RBiSO(4) (3), respectively. RBi(NO(3))(2) (4) was obtained from RBiCl(2) and AgNO(3) (1 : 2 molar ratio). The ionic complex [R(2)Bi][W(CO)(5)Cl] (6) was obtained from R(2)BiCl (5) and W(CO)(5)(THF), following an unusual chlorine transfer from bismuth to tungsten. Compounds 2-4 are partially soluble in water. The molecular structures of 2·0.5CH(2)Cl(2), 3, 4·H(2)O and 6 were established by single-crystal X-ray diffraction. The carbonate 2 and the sulfate 3 exhibit a polymeric structure based on bridging oxo anions, while for the compound 4 dimer associations are formed, with both bridging and terminal nitrate anions. Dimer associations, based on weak Cl···H interactions between the cation and the anion, were found in the crystal of 6.

Dipyrazinyl Sulfoxide Complexes of Silver(I), Zinc(II), and Cadmium(II): Ligation Modes and Anion Tuning

The new ligand dipyrazinyl sulfoxide (also named sulfinyldipyrazine and abbreviated as pyz(2)SO) and a series of its metal complexes including {[Ag(pyz(2)SO)](NO(3)).CH(3)CN}(infinity) (1), {[Ag(pyz(2)SO)](PF(6))}(infinity) (2), [Ag(3)(pyz(2)SO)(2)(ClO(4))(3)](infinity) (3), [Ag(pyz(2)SO)(CF(3)CO(2))](infinity) (4), {[Zn(pyz(2)SO)(H(2)O)(4)](NO(3))(2).H(2)O}(infinity) (5), {[Zn(pyz(2)SO)(H(2)O)(2)](ClO(4))(2)}(infinity) (6), and {[Cd(pyz(2)SO)(2)(H(2)O)](ClO(4))(2).H(2)O}(infinity) (7) have been synthesized and characterized by single-crystal X-ray analysis. The counteranions in these complexes prefer to be embraced by a pair of pi-acidic heterocyclic rings via anion-pi interactions, which consequently affect the process of supramolecular assembly. Seven distinct ligation modes of pyz(2)SO involving various bonding combinations of the sulfoxide oxygen and/or pyrazinyl nitrogen atoms (labeled A-G) are observed. Diverse coordination motifs such as (4,4) network, ladder-type, necklace-like, linear, and zigzag-chain structures are found in 1-7. Interestingly, the sulfoxide group of the pyz(2)SO ligand exhibits unusual dipolar sulfinyl...sulfinyl and S=O...pi(pyrazinyl) intermolecular interactions in the supramolecular assemblies of neat pyz(2)SO, 1, and 3-5.

Stereochemistry of the C−S Bond Cleavage in cis-2-Methylcyclopentyl Phenyl Sulfoxide Radical Cation

The TiO(2) photocatalyzed oxidation of cis-2-methylcyclopentyl phenyl sulfoxide in the presence of Ag(2)SO(4) in MeCN/H(2)O leads to the formation of 1-methylcyclopentanol, 1-methylcyclopentyl acetamide, and phenyl benzenethiosulfonate as the main reaction products. It is suggested that the C-S heterolysis in the radical cation is an unimolecular process leading to an ion radical pair. Fast 1,2-hydride shift in the secondary carbocation leads to 1-methylcyclopentyl carbocation that forms the observed products by reaction with H(2)O and MeCN. Attack of H(2)O on the ion radical pair may also occur, but as a minor route (<3%), with formation of trans-2-methylcyclopentanol.

Ag(I) coordination polymers with flexible bis-imidazole ligands: 2D interwoven structure and wavy layer network based on silver–silver interactions

Two new coordination polymers [Ag(BIM)SO 3CF 3] n ( 1) and [Ag(2-mBIM)NO 2] n ( 2) [wherein BIM = bis(imidazol-1-yl)-methane, 2-mBIM = bis(2-methylimidazol-1-yl) methane], were synthesized by the reactions of AgSO 3CF 3 with BIM and AgNO 2 with 2-mBIM, respectively. They were characterized by elemental analyses, IR, TGA and single crystal X-ray diffraction studies. Compound 1 is an example of silver coordination network with 2D fabric structure in a “one-over/one-under” fashion through weak Ag…Ag interactions. Compound 2 adopts a wavy 2D layer network constructed through the Ag…Ag interactions between each neighboring 1D zigzag chains. TGA measurements suggest that 1 and 2 are thermally quite stable, with decomposition temperatures being 355 °C and 230 °C, respectively. Solid state luminescent spectra of compounds 1 and 2 indicate weak fluorescent emissions at ca. 345 and 409 nm, respectively.

TOF-SIMS investigations on weathered silver surfaces

Silver-coated quartz crystal microbalance (QCM) disks were treated under different environmental conditions (including changes in parameters such as relative humidity (%RH) and SO(2)/H(2)S content) in atmospheres of synthetic air and pure N(2) for 24 h in a weathering chamber. The corroded surfaces were subjected to depth profiling by a time of flight (TOF) secondary ion mass spectrometry (SIMS) instrument, equipped with a Bi(+) analysis gun and Cs(+) sputter gun. The evaluation of the in-depth distribution of several elements and species provides evidence for the formation of a corrosion layer containing Ag(2)SO(3), even in the absence of oxidizing agents, such as H(2)O(2) or NO(2). Furthermore it could be elucidated that the thickness of the formed Ag(2)SO(3) layer does not depend on the SO(2) concentration but rather on the humidity and oxygen content of the ambient atmosphere. In weathering experiments in atmospheres composed of synthetic air, humidity, and H(2)S, the presence of different oxygen species (surface and bulk) and silver sulfide could be detected by TOF-SIMS depth profiling experiments. The obtained results for both acidifying gases are in good correlation with the corresponding tapping mode atomic force microscopy (TM-AFM) investigations and in situ QCM measurements.

Electroless Synthesis of Ag Nanoparticles on Deposited Nanostructured Si Films

Two and three-dimensional Ag nanoparticle ensembles were synthesized on deposited nanostructured column-void Si films simply by film immersion into pure Ag(2)SO(4) or AgNO(3) solutions. In addition to functioning as a reducer, this nanostructured material provides immobilization and monodispersion of the Ag nanoparticles due to its systematic nanoscale topography. This is accomplished without the requirement of a surfactant, capping agent, or linker. Kinetics, as monitored from plasmon optical extinction, and infrared spectroscopy suggest accompanying oxide growth limits and finally inhibits synthesis enabling nanoparticle size control. Kinetics is also limited by Ag+ transport through the voids unless the Si film is ultrathin. Our synthesis approach offers significant advantages for surface-enhanced molecular detection, including the absence of any agents on the nanoparticle surfaces and the ability to obtain nanoparticle ensembles on any substrate.

Enantiomerically Pure [1, 2‐Diamino‐1‐(4‐fluorophenyl)butane]platinum(II) Complexes: Synthesis and Antitumor Activity against MCF‐7 and MDA‐MB 231 Breast Cancer and LnCaP/FGC Prostate Cancer Cell Lines

Enantiomerically pure 1, 2-diamino-1-(4-fluorophenyl)butanes were synthesized by stereoselective procedures. The enantiomeric purity was determined by (1)H NMR spectroscopy after derivatization with (1R)-myrtenal. For the coordination to platinum, the diamines were reacted with K(2)PtI(4). Reaction with Ag(2)SO(4) yielded the respective sulfatoplatinum(II) complexes, which were converted into the dichloroplatinum(II) complexes by treatment with 2 N HCl. The influence of the configuration and the kind of leaving group on the antitumor activity was studied on the MCF-7 and MDA-MB 231 breast cancer cell lines, as well as on the LnCaP/FGC prostate cancer cell line. It was demonstrated that the dichloroplatinum(II) complexes were more active than the respective diiodoplatinum(II) derivatives. Conversion into the sulfatoplatinum(II) complexes further enhanced the antiproliferative effects. The configuration determined the antitumor effects, dependent on the cell line used: MCF-7: (R, R) > (S, S) > (R, S) > (S, R); MDA-MB 231: (S, S) > (R, R) > (R, S) = (S, R); LnCaP/FGC: (S, S) > (R, R) > (R, S) > (S, R).