Gen-etsu Matsubayashi

Synthesis and properties of tungsten(0) carbonyl complexes with carbonyl-stabilized ylides

The reactions of dimethylsulfonium, triphenylphosphonium, and 4-methylpyridinium phenacylides (PhC(O)CHZ+; Z+ = S+Me2 (Y Ph-S) P+Ph3 (Y Ph-P, and N+C5H4Me-4 (Y Ph-N)) with W(CO)5THF gave W(CO)5(PhC(O)CHZ+. IR and 1H NMR spectra have indicated the ylide carbon-to-tungsten linkage in W(CO)5YPh-S and the coordination of the carbonyl oxygen atom in W(CO)5YPh-P and W(CO)5YPh-N. The corresponding three 2-pyridylcarbonylmethylides (C5H4NC(O)CHZ+; Z+ = S+Me2 (YPy-S), P+Ph3 (YPy-P), and N+C5H4Me-4 (YPy-N)) reacted with W(CO)6 under UV irradiation or with W(CO)5THF to afford W(CO)4(C5H4NC(O)CHZ+. W(CO)4YPy-S(red form), W(CO)4YPy-P, and W(CO)4YPy-N have been suggested to involve the chelation through carbonyl oxygen and pyridine nitrogen on the basis of IR and 1H NMR spectra. Another geometrical isomer of W(CO)4YPy-S isolated as a brown form showed the same spectral behaviors as the red complex in solution. Configurations and properties of the complexes have been discussed on the basis of IR and 1H NMR, together with electronic absorption and emission spectra.

Syntheses and electrical resistivities of TTF and TSF salts with tris(oxalato)silicate, -germanate, and -stannate

Abstract Several tetrathiafulvalene (TTF) and tetraselenafulvalene (TSF) salts of tris(oxalato)silicate, -germanate, and -stannate, (TTF) x [X(C 2 O 4 ) 3 ]·nCH 3 CN (x = 2 and n = 0.5 for M = Si and Ge, and x = 2.8 and n = 0 for M = Sn) and (TSF) 2 [M(C 2 O 4 ) 3 · nCH 3 CN (n 0 for M = Si, Sn and n = 0.5 for M = Ge), have been prepared by the reaction of (TTF) 3 (BF 4 ) 2 or (TSF) 3 (BF 4 ) 2 with [R 4 N] 2 [M(C 2 O 4 ) 3 ] (R = Et or n-Bu) in acetornitrile. Electrocrystallization for the TTF[Et 4 N] 2 [Sn(C 2 O 4 ) 3 ] and TSF[Et 4 N] 2 [Ge(C 2 O 4 ) 3 ] systems in acetonitrile afforded (TTF) 2.8 [Sn(C 2 O 4 ) 3 ]·0.5SH 3 CN and (TSF) 2 [Ge(C 2 O 4 ) 3 ], respectively. Electrical resistivities of the TTF salts as compacted samples at 25°C fall in the range 10 4 –10 5 Ω cm and those of the TSF salts in the range 10 3 –10 4 Ω cm. Electronic reflectance spectra of the TTF and TSF salts show bands at 13 30013 600 cm −1 and 11 40012 500 cm −1 due respectively to the (TTF ??? ) 2 and (TSF ??? ) 2 dimers. In addition, (TTF) 2.8 [Sn(C 2 O 4 ) 3 exhibited a band at 8900 cm −1 , ascribed to a charge transfer transition between neutral TTF and the TTF ??? radical cation. All the salts display weakly diamegnetic properties, consistent with the appearance of anisotropic weak ESR signals attributable to the TTF ??? and TSF ??? radical cations.

PMR and thermodynamic studies of dimethyltin dichloride/picolinaldimine adducts☆

Stable dimethyltin dichloride adducts with several picolinaldimines (C5H4NCHNR, RCH3, C6H4OCH3-p, C6CH4CH3-p, C6H4CH3-p, C6H4Cl-p) have been isolated and the configurations in solution have been discussed on the basis of PMR spectra of the complexes. Equilibrium constants of the adducts in acetonitrile have been determined from the 119SnCH3 coupling constants of dimethyltin dichloride. Heats of complex formation in acetonitrile have also been measured by calorimetry, and thermodynamic parameters in the complex formation have been obtained.

Preparation and properties of bis(oxalato)platinate and bis(1,3-dithiole-2 thione-4, 5-dithiolato)metallate (M = Ni, Pd, and Pt) anion salts with the 1,4-diethylpyrazinium dication

Abstract Reactions of [Pt(C 2 0 4 ) 2 ] 2− (C 2 0 4 2−  oxalate anion) and [M(C 3 S 5 ) 2 ] m− (C 3 S 5 2−  1,3-dithiole-2- thione-4,5-dithiolate anion; m  2 for Ni, Pd and Pt; m = 1 for M  Ni and Pt) with the 1,4-diethylpyrazinium dication (DEPZ 2+ ) in acetonitrile gave partially oxidized metallate-anion salts: [DEPZ] 0.9 [Pt(C 2 0 4 ) 2 ] and [DEPZ] 0.3–0.35 [M(C 3 S 5 ) 2 ] (M  Ni, Pd and Pt). They behave as typical semiconductors in the temperature range of −30–+40 °C; electrical resistivities of the [Pt(C 2 0 4 ) 2 ] and [M(C 3 S 5 ) 2 ] salts are 3.7 × 10 5 and 13−620 Ω cm, respectively, at 25 °C for compacted peltets. IR and X-ray photoelectron spectra indicate that the partial oxidation of [M(C 3 S 5 ) 2 ] m− by DEPZ 2+ occurs essentially at the dithiolato ligand.

X-Ray crystal structure of bis(N-ethylpyridinum) bis[4,5-dimercapto-1,3-dithiole-2-thionato(2–)]cuprate(II) and electrical properties of its oxidized salts

A single-crystal X-ray structure analysis has been performed for the complex bis(N-ethylpyridinium) bis[4,5-dimercapto-1,3-dithiole-2-thionato(2–)]cuprate(II). The crystals are monoclinic, space group C2/m, with Z= 4, a= 20.04(2), b= 14.56(2), c= 10.19(1)A, and β= 109.2(1)°. Block-diagonal least-squares refinement, based on 1 882 independent reflections with |F∘| > 3σ(F), converged at R= 0.077. The geometry around the copper atom is greatly distorted from a square-planar one, with a dihedral angle of 57.3° between the dithiolato ligand planes. While the complex behaves almost as an insulator, with an electrical conductivity of 7.1 × 10–10S cm–1 measured for a compacted pellet at 25 °C, some partially oxidized bis[4,5-dimercapto-1,3-dithiole-2-thionato(2–)]copper complexes exhibit increased conductivities of 10–6–10–5S cm–1.

EXTENDED BISDITHIOLENE METAL COMPLEXES : PREPARATION AND ELECTRICAL CONDUCTIVITIES OF M(C8H4S8)2 ANION COMPLEXES (M = NI(II), PT(II), AU(III))

A precursor compound of the new dithiolato ligand with an extended π-electron system, C8H4S82− (2-[(4,5-ethylenedithio)-1,3-dithiole-2-ylidene]-1,3-dithiole-4,5-dithiolate), was synthesized. [NBun4][Au(C8H4S8)2], [NBun4]0.06[Au(C8H4S8)2], Na1.5[Ni(C8H4S8)2] and [NBun4]0.4[Pt(C8H4S8)2] were prepared. The partially oxidized species exhibit electrical conductivities of 0.2–17S cm−1 at room temperature as compacted pellets. The redox potentials of the gold(III) complex were determined. IR, electronic absorption and powder reflectance spectra of the complexes as well as the X-ray photoelectron spectra are discussed.

Spectroscopy and electrical conductivity of [Au(C3S5)2]n– and [Au(C3Se5)2]n–(n= 0–1) complexes and X-ray crystal structure of [NBun4][Au(C3S5)2]

The complexes [NBun4][Au(C3S5)2][C3S52–= 4,5-dimercapto-1,3-dithiole-2-thionate(2–)] and [NBun4][Au(C3Se5)2][C3Se52–= 4,5-di(hydroseleno)-1,3-diselenole-2-selonate(2–)] were prepared. Oxidation reactions of these complexes with iodine, [ttf]3[BF4]2(ttf˙+= the tetrathiafulvalenium radical cation), and [Fe(cp)2][PF6](cp =η-C5H5) afforded [Au(C3S5)2], [Au(C3Se5)2], [ttf][Au(C3S5)2], [ttf]0.3[Au(C3Se5)2], [Fe(cp)2]0.25[Au(C3S5)2], and [Fe(cp)2]0.2[Au(C3Se5)2], respectively. Controlled-current electrolysis of [NBun4][Au(C3S5)2] in acetonitrile containing an excess of [NBun4][ClO4] afforded [NBun4]0.22[Au(C3S5)2]. The complexes [Au(C3S5)2] and [Au(C3Se5)2] have electrical conductivities of 5.0 × 10–4 and 6.3 × 10–4 S cm–1, the ttf complexes 4.3 × 10–3 and 3.2 × 10–3 S cm–1, respectively, and the other partially oxidized complexes 0.10–0.16 S cm–1 at 25 °C for compacted pellets. Ligand-centred oxidation is believed to occur for both the [Au(C3S5)2]n– and [Au(C3Se5)2]n–(n 3σ(F), converged at R= 0.034.

Spectroscopic and electrical properties of the PtIIS2N2 type complexes and their iodine-doped analogs

Abstract Pt(dmit)(L) (dmit 2− = the 1,3-dithiole-2-thione- 4,5-dithiolate anion; L = 2,2′-bipyridine, 1,10- phenanthroline, 4,4′-dimethyl-2,2′-bipyridine, N -ethyl- 2-picolinaldimine, and N -isopropyl-2-picolinaldimine) have been prepared. They are polarized in the ground stare, exhibiting a ligand-to-ligand charge transfer absorption band in the 8000-14000 cm −1 region. These complexes behave as semi-conductors with electrical conductivities of 1 × (10 −9 ∼ 10 −11 ) S cm −1 at 25 °C as compacted pellets. On doping iodine into the complexes, they have been partially oxidized to afford Pt(dmit)(L)·I x ( x = 1.9 ∼ 2.3) containing I 3 − and I 5 − ions, whose electrical conductivities are raised by two to four powers compared with those of corresponding Pt(dmit)(L) complexes. IR, Raman, and ESR spectra of the iodine-doped complexes are discussed.

Preparation and properties of C8H4S8-platinum(II) complexes and electrical conductivities of their oxidized species and X-ray crystal structure of C8H4S8(CH2CH2CN)2 as a pro-ligand compound

Abstract Using the C8H4S82− ligand [2-[(4,5-ethylenedithio)-1,3-dithiole-2-ylidene]-1,3-dithiole-4,5-dithionate(2-)] as an extended π-electron system, [NBun4]2[Pt(C8H4S8)2] and Pt(Et2S)2(C8H4S8) were prepared. They were oxidized by the ferrocenium, the decamethylferrocenium cation or iodine to form [NBun4]8[Pt(C8H4S8)2] (x=0.05−0.4) and Pt(C8H4S8) (Et2S)0.3I1.8, which exhibited electrical conductivities of 1.1–6.9 S cm−1, measured for compacted pellets at room temperature. The crystal structure of the pro-ligand compound. C8H4S8(CH2CH2CN)2, revealed a one-dimensional array of dimerized molecules constructed with some sulfur-sulfur non-bonded contacts.

Thermodynamic study of complex formation: 2,2′-bipyridine and some organotin and tin tetrachloride systems

Abstract The formation constants of 2,2′-bipyridine complexes of dialkyltin dichlorides, n -butyltin trichloride, and tin tetrachloride in acetonitrile have been determined spectroscopically. The heats of reaction in acetonitrile solution for these systems have been also determined by a conventional calorimeter of Dewar vessel type. From these results, free energy, enthalpy and entropy changes of these complex formations have been calculated. While, heats of solution of n -butyltin trichloride and tin tetrachloride in acetonitrile and heats of mixing of carbon tetrachloride solutions of some alkyltin chlorides with acetonitrile have been measured, and tin tetrachloride in acetonitrile has been found to be strongly co-ordinated by the solvent molecules. The order of co-ordinate bond strengths of 2,2′-bipyridine to alkyltin chlorides and tin tetrachloride is: SnCl 4 > n -C 4 H 9 SnCl 3 > (CH 3 ) 2 SnCl 2 ≅ (C 2 H 5 ) 2 SnCl 2 > ( n -C 4 H 9 ) 2 SnCl 2 . The u.v. spectra of complexes of 2,2′-bipyridine and tin chlorides have been discussed.