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[NEt4][Pt(ppy)(C3S5)] (ppy−= C-deprotonated 2-phenylpyridine(−); C3S52−= 4,5-disulfanyl-1,3-dithiole-2-thionate(2−)), [NEt4]-, [NBun4][Pt(ppy)(C8H4S8)] (C8H4S82−= 2-{(4,5-ethylenedithio)-1,3-dithiole-2-ylidene}-1,3-dithiole-4,5-dithiolate(2−)) and [NEt4][Pt(ppy)(C10–C6S8)] (C10–C6S82−= 2-{bis(decylthio)-1,3-dithiole-2-ylidene}-1,3-dithiole-4,5-dithiolate(2−)) were prepared. They showed an intense electronic absorption band due to an intramolecular mixed metal/dithiolate ligand-to-ppy ligand charge transfer transition, which is somewhat sensitive to the solvent. The complexes exhibited first oxidation potentials of −0.27 to +0.02 V (vs Ag/Ag+) due to the dithiolate ligand-centered oxidation. They were oxidized by TCNQ and iodine to afford [Pt(ppy)(L)] and [Pt(ppy)(L)](I1.0–4.2) (L = C3S52−, C8H4S82−, and C10–C6S82−). Electrical conductivities of the oxidized C8H4S8- and C10–C6S8-species measured for compacted pellets at room temperature were 6.2 × 10−6–7.8 × 10−3S cm−1, while those of the oxidized C3S5-species were very low [(3.8–6.2) × 10−9S cm−1]. The X-ray crystal structure of [NBun4][Pt(ppy)(C8H4S8)] was clarified.

[Rh(η⁵-C5H5)(C8H4S8)] and [M(η⁵-C5Me5)(C8H4S8)] [M = Rh^III and Ir^III. C8H4S8²⁻ = 2-{(4,5-ethylenedithio)-1,3-dithiole-2-ylidene}-1,3-dithiole-4,5-dithiolate(2−)] were prepared by reactions of [NMe4]2[C8H4S8] with [Rh(η⁵-C5H5)Cl2]2 or [M(η⁵-C5Me5)Cl2]2 (M = Rh and Ir). They exhibit oxidation potentials of between +0.16 and +0.24 V (versus Ag/Ag⁺) with oxidation of the dithiolate ligand. The geometries and electronic states of their one-electron-oxidized species [M(L)(C8H4S8)]⁺ and [RhX(L)(C8H4S8)] (M = Rh and Ir; X = Br and I; L = η⁵-C5H5 and η⁵-C5Me5), obtained by reactions of the above complexes with bromine, iodine, or the ferrocenium cation are discussed based on their ESR spectra. The oxidized η⁵-C5Me5-metal complexes exhibit electrical conductivities of between 10⁻⁶ and 10⁻⁴ S cm⁻¹, while some oxidized η⁵-C5H5-Rh complexes show conductivities of between 10⁻³ and 10⁻² S cm⁻¹ measured for compacted pellets at room temperature. The X-ray crystal structures of the two-electron-oxidized species [MI(η⁵-C5Me5)(C8H4S8)](I3) (M = Rh and Ir) were also clarified. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Crystals of [Au(ppy)(C8H4S8)]2[PF6] [ppy⁻ = C-deprotonated 2-phenylpyridine(−); C8H4S8²⁻ = 2-{(4,5-ethylenedithio)-1,3-dithiol-2-ylidene}-1,3-dithiole-4,5-dithiolate(2−)] were prepared by current-controlled electrolysis of a benzonitrile solution of [Au(ppy)(C8H4S8)] with [NEt4][PF6] as an electrolyte. The X-ray crystal structure analysis revealed the formation of a columnar stacking of two crystallographically independent cations in formally the 0.5-electron-oxidized state. Cation moieties with some S−S non-bonded contacts (< 3.7 Å) along the a and b axes form a two-dimensional sheet, with the molecular interaction parallel to the ab plane. The electrical conductivities measured for a crystal at room temperature were 9.2 and 0.0028 S cm⁻¹ along the a and c axes, respectively. From the activation energy for the electron conduction determined by the conductivities measured for a compacted pellet the complex was estimated to be metallic from room temperature to 110 K. The energy-band calculation for the oxidized species showed two-dimensional electron conduction through the column. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

[Pt(bpy)(C 8 H 4 S 8 )][BF 4 ] (bpy=2,2′-bipyridine; C 8 H 4 S 8 =2-{(4,5-ethylenedithio)-1,3-dithiole-2-ylidene}-1,3-dithiole-4,5-dithionate(2-)) was prepared by current-controlled electrolysis of a dichloromethane solution of [Pt(bpy)(C 8 H 4 S 8 )] with [NEt 4 ][BF 4 ] as an electrolyte. The X-ray crystal structure analysis revealed a columnar stacking of the one-electron oxidized, cationic moieties with some S-S non-bonded contacts (<3.7 A˚) as well as an S-S layered interaction in another direction. The electrical conductivity measured for a compacted pellet was 5.0×10 S cm at room temperature with activation energy of 0.05 eV. The energy band calculation of the oxidized species showed an essentially one-dimensional electron-conduction through the column.

The [Cation]+ATCNQ−type salts were prepared, where ATCNQ−is (4-dicyanomethyl-1-pyridinio)dicyanomethanide anion, so-called AzaTCNQ−anion, and [Cation]+are N-alkylpyridinium, 4-cyano-N-alkylpyridinium, (4-methyl-1-pyrazinio)dicyanomethanide, N-alkylquinolinium (alkyl=Me and Et), N-methylacridinium, and N-methylphenazinium. Electrical resistivities of these salts as compacted samples fall in the range 106–109Ωcm at 25 °C. The mixed ATCNQ−/TCNQ\ewdotsalts (TCNQ\ewdot=7,7,8,8-tetracyano-p-quinodimethan radical anion) of N-alkylpyridinium and -quinolinium cations also were prepared; [Cation]+(ATCNQ−)0.1(TCNQ\ewdot)0.9([Cation]+=N-methylpyridinium, N-ethylpyridinium, and N-ethylquinolinium) and [N-methylquinolinium]+(ATCNQ−)0.17(TCNQ\ewdot)0.83whose electrical resistivities (104–106Ωcm at 25 °C) are somewhat smaller than those of the corresponding TCNQ\ewdotsalts. Stackings of ATCNQ−and TCNQ\ewdotanions are discussed on the basis of electronic reflectance and ESR spectra. The [Cation]+ATCNQ−salts react with iodine in hexane to give [Cation]+ATCNQ−·Ix([Cation]+=N-methyl- and N-ethylpyridinium and -quinolinium; x=3.2–3.9). They exhibit electrical resistivities of 104–106Ωcm at 25°C, which are lower by the 102–103order than the resistivities of the undoped [Cation]+ATCNQ−salts.

A β,β-dimethyl-substituted ketene silyl acetal reduces p-chloranil to produce the carbon-oxygen adduct, the hydrolysis of which yields the corresponding hydro-quinone ether (3). The structure of 3has been determined by the X-ray crystal analysis. On the other hand, the reaction of a nonsubstituted ketene silyl acetal with p-fluoranil yields the carbon-carbon adduct selectively. The mechanistic difference between the C-O and C-C bond formation is elucidated based on the kinetic study.

The title salt has been obtained By electrolysis of dibenzotetrathiafulvalene in a benzonitrile solution containing dichlorodimethyltin(IV) and benzyltriphenylphosphonium chloride. The X-ray crystal analysis has revealed the presence of a DBTTF columnar structure and a novel trimerized tin(IV) anion [Sn3(CH3)6Cl8]2−. Electrical and spectroscopic properties also are described.

Several tetrathiafulvalene (TTF) and tetraselenafulvalene (TSF) salts of tetrahalogenozinc(II) and ‐cadmium(II) anions Dx[MX4] (D = TTF or TSF; M = Zn and Cd; X = Cl, Br, and I; x= 2.0‐6.6) have been prepared by the reaction of [TTF]3[BF4]2or [TSF]3[BF4]2with [NEt4]2[MX4] in acetonitrile and by the electrolysis of TTF or TSF in acetonitrile containing [NEt4]2[MBr4]. Electrical resistivities of these salts measured for compressed pellets fall in the range 1 × (101–107) Ω cm at 25 °C; the value decreases with increasing bulkiness of the anions: [MCl4]2–> [MBr4]2−> [MI4]2−. Stackings and electronic states of TTF and TSF molecules are discussed on the basis of electronic reflectance, ESR, IR, and Raman spectra.

ß-Isomers of A-type vanadium-trisubstituted nonatungstophosphate anion salts were synthesized by a condensation of NaVO3and A-Na9[PW9O34]·7H2O in an aqueous hydrochloric acid and 1,4-dioxane mixed solution. Their geometries were characterized by IR, 31P, 51V, and 183W NMR spectroscopies. The tetrabutylammonium salt of the ß-isomer, A-ß-(NBun4)4H2[PV3W9O40], isomerizes to the corresponding a-isomer both in the solid state and in solution under mild conditions, which can be directly followed by FT-IR and 31P NMR spectroscopies. The kinetics of the isomerization in the solid state had a first-order rate constant at 40 °C, k1= 2.19 × 10-7(s-1), together with ?H‡= 93.3 (kJ mol-1) and ?S‡= -77.3 (J K-1mol-1). On the other hand, A-ß-Cs6[PV3W9O40] and A-ß-(NBun4)6[PV3W9O40], which have no protons in the cation part, do not isomerize under the same conditions. The ß-to-aisomerization is promoted by protonation at the bridging oxygen atom in the W–O–W bond of the polyanion.

S,S-Dimethylsulfonium 2-picolinylmethylide (PyC(O) \barCH+SMe2, Ydms) reacts with PtCl2(SMe2)2to give PtCl2Ydmsand PtCl(SMe2)(PyC(O)CHCl); the former involves the coordination of both the pyridine nitrogen and ylide carbon atoms, and the latter is a complex with the 2-picolinylchloromethyl ligand which is formed by the fission of the ylide carbon to sulfur bond. An X-ray structure of the latter complex is determined.

The kinetics of the oxygen-atom transfer reactions of α-[NBun4]3[PMo12O40] (abbreviated PMo12) and of A-β-[NBun4]3[PMo3W9O40] (abbreviated PMo3W9) with PPh3were investigated in acetonitrile at 23—82 °C. Each reaction is first order in both the heteropolyanion salt and PPh3. The second-order rate constants at 23 °C are k2= 6.53 × 10−4and 4.58 × 10−5(dm3mol−1s−1) for the reduction of PMo12and PMo3W9, respectively. The difference in the k2values is attributed to the number of active sites for oxygen transfer; PMo3W9has only three corner-sharing oxygen atoms in the Mo(VI)–O–Mo (VI) bonds, whereas there are twelve corner-sharing and twelve edge-sharing oxygen atoms in PMo12. The activation parameters are, however, almost identical for both reactions: ΔH‡= 43.6 and 43.4 (kJ mol−1) and ΔS‡= −158 and −181 (J K−1mol−1) for the reduction of PMo12and PMo3W9, respectively. These results suggest a similar transition state in the oxygen-atom transfer reactions via the Mo–O–Mo sites of PMo12and PMo3W9.

Cationic palladium(II) complexes of the di-t-butylnitroxide radical, [Pd(But2NO)(L-L)]X (L-L=2,2′-bipyridine, 1,10-phenanthroline, N-substituted 2-pyridylmethyleneamine and bis(triphenylphosphine); X−=ClO4-and/or BPh4−), were prepared. 1H NMR spectra of the complexes indicate that the nitroxide forms a three membered ring with the palladium atom. The N-methyl- and N-ethyl-2-pyridylmethyleneamine complexes exist as two geometrical isomers in solution, whose ratios are 1 : 1 and 1 : 0.2, respectively. In the N-butyl and N-p-tolyl analogs, however, only one of the isomers exists in solution. These results are interpreted in terms of steric repulsion between the t-butyl groups and N-substituents. The bipyridine complex reacts with dialkyl disulfides in the presence of catalytic amounts of bipyridine to give a sulfur-bridged dimeric complex, [Pd(bipyridine)(SR)]2(ClO4)2(R=Me and Pr), and a free nitroxide radical.

PdX(But2NO)L (L=PPh3, AsPh3, P(OPh)3; X=Cl, Br, I) was isolated by the reactions of [PdCl(But2NO)]2with L and by the halogen exchange reactions of the chloro complexes with LiBr·H2O or NaI. PMR and IR spectra revealed that PdX(But2NO)(PPh3) and PdX(But2NO)(AsPh3) exist as only one geometrical isomer with the halogen atom transto the oxygen atom of the nitroxide ligand, while two isomers of PdX(But2NO)[P(OPh)3] coexist in solution. The reaction of PdX(But2NO) (PPh3) (X=Cl, I) with triphenylphosphine was found to give Pd(PPh3)4together with Pd X2(PPh3)2and Bu2NO·. A similar reaction proceeded between PdCl(But2NO)[P(OPh)3] and triphenylphosphite to yield Pd[P(OPh)3]3, while a not well-defined complex [PdCl(AsPh3)2]nwas obtained in the reaction of PdCl(But2NO)(AsPh3) with triphenylarsine.

Ferrocene, FcH [Fc = (C5H5)Fe(C5H4)], (ferrocenylalkyl)trimethylammonium iodides, [Fc(CH2)nNMe3]+I-(n= 1 or 2), and 1,2-diferrocenylethane, FcCH2CH2Fc, have been intercalated into the V0.21Nb0.79OPO4interlayer space. The V(V) ion is reduced by the iodide ion and/or the Fc centers, the Nb(V) ion being not reduced. The long-axis direction of the guest molecules is arranged approximately parallel to the swelling V0.21Nb0.79OPO4sheet. Some Fc centers of FcCH2CH2Fc and FcCH2CH2NMe3+are not oxidized in spite of their proximity to the metal ion site of the V0.21Nb0.79OPO4lattice because most of the V sites are isolated from other V sites owing to the low V contents. Ferrocenylalkylamines, FcCH2NMe2and FcCH2CH2NH2, have been intercalated into the VxNb1-xOPO4(x= 0, 0.06, 0.11, and 0.21) interlayer spaces, accompanied with the protonated amino groups and the Nb(V) and reduced V(IV) sites. ESR signals of the V0.06Nb0.94OPO4intercalation compounds exhibit hyperfine structures due to the V(IV) nucleus (I= 7/2). With the increase of the V content in the host lattice, ESR signals are further broadened owing to the dipole–dipole and/or exchange interactions among the V(IV) sites.

The chemical shifts of methyl protons (t(M–CH3) values) and the coupling constants between the methyl protons and the metal atom JM–CH3values for dimethyltin dichloride, trimethyltin chloride, and trimethyllead chloride have been measured in thirty-two organic solvents. From the relation between the t(M–CH3) and the JM–CH3values, the solvents used here have been classified into four groups. Carbon tetrachloride is representative of the first groups. The second group consists of usual polar organic solvents which can coordinate to the metal atom. The third consists of nitrobenzene, benzonitrile, pyridine, and its derivatives among the solvents studied here. The fourth consists of alkyl- or halogen-substituted aromatic solvents. The configurations of trimethyltin chloride in these solvents have been discussed on the basis of the J119Sn-CH3values and the intensity of the Sn–C symmetric stretching band relative to that of the asymmetric one. The effects of the temperature and the concentration of the solute on the t(Sn–CH3) and the J119Sn-CH3values of trimethyltin chloride have been examined in several solvents.

Several new stable ylide complexes formed between palladium(II) and platinum(II) dihalides and S,S-dimethyl-N-benzoyl- or S,S-dimethyl-N-p-methylbenzoylsulfilimine were isolated and the coordination through the ylide-nitrogen atom is concluded.