Synthese und spektroskopische Charakterisierung von [Rh(SeCN)6]3– und trans‐[Rh(CN)2(SeCN)4]3–, Kristallstruktur von (Me4N)3[Rh(SeCN)6]

Synthesis and Spectroscopic Characterization of [Rh(SeCN)₆]^3– and trans ‐[Rh(CN)₂(SeCN)₄]^3–, Crystal Structure of (Me₄N)₃[Rh(SeCN)₆] Treatment of RhCl₃ with KSeCN in acetone yields a mixture of selenocyanato‐rhodates(III), from which [Rh(SeCN)₆]^3– and trans‐[Rh(CN)₂(SeCN)₄]^3– have been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X‐ray structure determination on a single crystal of (Me₄N)₃[Rh(SeCN)₆] (trigonal, space group R3, a = 14.997(2), c = 24.437(3) Å, Z = 6) reveals, that the compound crystallizes isotypically to (Me₄N)₃[Ir(SCN)₆]. The exclusively via Se coordinated selenocyanato ligands are bonded with the average Rh–Se distance of 2.490 Å and the Rh–Se–C angle of 104.6°. In the low temperature IR and Raman spectra the metal ligand stretching modes ν(RhSe) of (n‐Bu₄N)₃[Rh(SeCN)₆] ( 1 ) and trans‐(n‐Bu₄N)₃[Rh(CN)₂(SeCN)₄] ( 2 ) are in the range of 170–250 cm^–1. In 2 ν_as(CRhC) is observed at 479 cm^–1. The vibrational spectra are assigned by normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constants are f_d(RhSe) = 1.08 ( 1 ), 1.10 ( 2 ) and f_d(RhC) = 3.14 mdyn/Å ( 2 ). f_d(RhS) = 1.32 mdyn/Å is determined for [Rh(SCN)₆]^3–, which has not been calculated so far. The ¹⁰³Rh NMR resonances are 2287 ( 1 ), 1680 ppm ( 2 ) and the ⁷⁷Se NMR resonances are –32.7 ( 1 ) and –110.7 ppm ( 2 ). The Rh–C bonding of the cyano ligand in 2 is confirmed by a dublett in the ¹³C NMR spectrum at 136.3 ppm.     

Kristallstrukturen,spektroskopische Charakterisierung und Normalkoordinatenanalyse von (n‐Bu4N)2[M(ECN)4] (M = Pd,Pt; E = S,Se)

Crystal Structures, Spectroscopic Analysis, and Normal Coordinate Analysis of ( n ‐Bu₄N)₂[M(ECN)₄] (M = Pd, Pt; E = S, Se) The reaction of (NH₄)₂[PdCl₄] or K₂[PtCl₄] with KSCN or KSeCN in aqueous solutions yields the complex anions [Pd(SCN)₄]^2–, [Pt(SCN)₄]^2– and [Pt(SeCN)₄]^2–, which are converted into (n‐Bu₄N) salts with (n‐Bu₄N)HSO₄. (n‐Bu₄N)₂[Pd(SeCN)₄] is formed by treatment of (n‐Bu₄N)₂[PdCl₄] with (n‐Bu₄N)SeCN in acetone. X‐ray structure determinations on single crystals of (n‐Bu₄N)₂[Pd(SCN)₄] (monoclinic, space group P2₁/n, a = 13.088(3), b = 12.481(2), c = 13.574(3) Å, β = 91.494(15)°, Z = 2), (n‐Bu₄N)₂[Pd(SeCN)₄] (monoclinic, space group P2₁/n, a = 13.171(2), b = 12.644(2), c = 13.560(2) Å, β = 91.430(11)°, Z = 2) and (n‐Bu₄N)₂[Pt(SeCN)₄] (monoclinic, space group P2₁/n, a = 13.167(2), b = 12.641(1), c = 13.563(2) Å, β = 91.516(18)°, Z = 2) reveal, that the compounds crystallize isotypically and the complex anions are centrosymmetric and approximate planar. In the Raman spectra the metal ligand stretching modes of (n‐Bu₄N)₂[Pd(SCN)₄] ( 1 ) and (n‐Bu₄N)₂[Pt(SCN)₄] ( 3 ) are observed in the range of 260–303 cm^–1 and of (n‐Bu₄N)₂[Pd(SeCN)₄] ( 2 ) and (n‐Bu₄N)₂[Pt(SeCN)₄] ( 4 ) in the range of 171–195 cm^–1. The IR and Raman spectra are assigned by normal coordinate analysis using the molecular parameters of the X‐ray determination. The valence force constants are f_d(PdS) = 1.17, f_d(PdSe) = 1.17, f_d(PtS) = 1.44 and f_d(PtSe) = 1.42 mdyn/Å. The ⁷⁷Se NMR resonances are 23 for 2 , –3 for 4 and the ¹⁹⁵Pt NMR resonances 549 for 3 and 130 ppm for 4 .     

N(SCl)2 ⊕[MoCl5(NSCl)]⊖, ein Chlorthionitrenokomplex von Molybdän(VI)

N(SCl)₂^⊕ [MoCl₅(NSCl)]^?, a Chlorothionitrene Complex of Molybdenum (VI) . The title compound is formed together with MoCl₃(N₃S₂) by the reaction of MoCl₄ or MoCl₅ with (NSCl)₃ in CH₂Cl₂. The black, crystalline compound was characterized by its i.r. spectrum and an X-ray crystal structure determination. N(SCl)₂^⊕[MoCl₅(NSCl)]^? crystallizes in the monoclinic space group P2₁/n with four formula units per unit cell. The lattice constants are a = 716.3, b = 1627.4, c = 1178.9 pm and β = 100.90°. The [MoCl₅(NSCl)]^? ion posseses an almost linear Mo = N = S grouping with bond lengths that can be interpreted as double bonds. Crystal data for AsPh₄[MoCl₅(NSCl)] are reported.     

Darstellung und spektroskopische Charakterisierung von bindungsisomeren Halogenoselenocyanato-Osmaten(IV) und -Rhenaten(IV)

Preparation and Spectroscopic Characterization of Bond Isomeric Halogenoselenocyanato-Osmates(IV) and -Rhenates(IV) By oxidative ligand exchange of appropriate chloro-iodo complexes of Os^IV or Re^IV with (SeCN)₂ in CH₂Cl₂ or by heterogeneous reaction with Pb(SeCN)₂ or AgSeCN in CH₂Cl₂ the new complexes cis-[OsCl₄(NCSe)(SeCN)]^2?, tr.-[OsCl₄Br(NCSe)]^2?, tr.-[OsCl₄Br(SeCN)]^2?, [ReCl₅(NCSe)]^2?, [ReCl₅(SeCN)]^2?, tr.-[ReCl₄I(NCSe)]^2?, tr.?[ReCl₄(NCSe)(SeCN)]^2? and tr.?[ReCl₄(NCSe)₂]^2? are formed and isolated as pure compounds by ion exchange chromatography on DEAE-cellulose. The bond isomers are significantly distinguished by the frequencies of innerligand vibrations: n?_CN(Se) > n?_CN(N); n?_CSe(N) > n?_CSe(Se); δ_NCSe > δ_SeCN. The electronic spectra (10 K) of the solid salts reveal a bathochromic shift for the charge transfer bands of the Se isomers as compared with the corresponding N isomers. The intra-configurational transitions are observed for the Os^IV complexes at 600 to 2400 and for the Re^IV complexes at 500 to 1600 nm. The ⁷⁷Se nmr signals of the Os^IV bond isomers are registrated for Se binding in the region 970 to 1040 ppm, for N coordination downfield at 1540 to 1640 ppm.     

Darstellung und spektroskopische Charakterisierung von Bindungsisomeren Halogenoselenocyanatoosmaten(IV)

Preparation and Spectroscopic Characterization of Bondisomeric Halogenoselenocyanatoosmates (IV) The new compounds [OsCl₅(NCSe)]^2?, [OsCl₅(SeCN)]^2?, tr.-[OsCl₄(NCSe)(SeCN)]^2?, tr.-[OsCl₄I(NCSe)]^2? and tr.-[OsCl₄I(SeCN)]^2? are prepared from [OsCl₅I]^2? and tr.-[OsCl₄I₂]^2? by oxidative ligand exchange with (SeCN)₂ or by reaction with suspended Pb(SeCN)₂ in CH₂Cl₂ and isolated by ion exchange chromatography on DEAE cellulose. The bondisomers are significantly distinguished by the frequencies of innerligand vibrations: ν_CN(Se), ν_CN(N), ν_CSe(N) > ν_CSe(Se), δ_NCSe >, δ_SeCN. The electronic spectra measured at 10 K on the solid salts exhibit in the region 450–650 nm intensive Se → Os and N → Os charge transfer bands. Essentially weaker intraconfigurational transitions (t) are observed near to 2000 and 1000 nm, splitted by lowered symmetry (C_4v) and spin orbit coupling. Only some of the 0–0-transitions may be assigned by measuring electronic Raman bands with the same frequencies.     

Darstellung und spektroskopische Charakterisierung von Di(acido)phthalocyaninatorhodaten(III)

Preparation and Spectroscopical Characterization of Di(acido)phthalocyaninatorhodates(III) Triethylendiaminorhodiumiodide reacts quickly and completely with boiling phthalodinitrile precipitating ?rhodiumphthalocyanine”?, which is purified and dissolved in alkaline media as di(hydroxo)phthalocyaninatorhodate(III). Acidification in the presence of halides or pseudohalides yields less soluble acidophthalocyaninatorhodium reacting with tetra-n-butyl-ammonium(pseudo)halide to give (blue)green tetra-n-butyl-ammoniumdi(acido)phthalocyaninatorhodate(III), (ⁿBu₄N)[Rh(X)₂Pc^2?] (X = Cl, Br, I, N₃, CN, NCO, SCN, SeCN). The asym. Rh? X-stretching vibration (v_as(RhX)) is observed in the f.i.r. at 290 (X = Cl), 233 (Br), 205 (I), 366 (N₃), 347 (CN), 351 (NCO), 257 (SCN) and 214 cm^?1 (SeCN). v_s(RhI) is the only sym. Rh? X-stretching vibration excited at 131 cm^?1 in the Raman spectrum. The m.i.r. and resonance Raman spectra are typical for hexacoordinated phthalocyaninatometalates(III). The influence of the axial ligands is very small. The frequency of the stretching vibrations of the pseudohalo-ligands are as expected (in the case of the ambident ligands the bonding atom is named first): v_as(NN) at 2006 and v_s(NN) at 1270 cm^?1 (N₃); v_as(CN) at 2126 (CN), 2153 (NCO), 2110 (SCN) and 2116 cm^?1 (SeCN). The characteristic π–π*-transitions of the Pc^2?-ligand dominate the UV-vis spectra. The splitting of the Q and N region is discussed and the weak absorbance at ca. 22 kK is assigned to a n–π*-transition.     

Preparation,characterization and electrical conductivity of new heterobimetallic chalcogenates and their 1,10-phenanthroline adducts

New mixed metal chalcogenate coordination polymers, MPb(SCN)₂(SeCN)₂ [M = Co^II, Ni^II or Hg^II], Ag₂-Pb(SCN)₂(SeCN)₂, and the complex heterobimetallic salts, [M(phen)₃][Pb(SCN)₂(SeCN)₂][M = Co^II or Ni^II; phen = 1,10-phenanthroline] that have been prepared and characterized by elemental analyses, i.r. and u.v.–vis. spectra, and by powder XRD patterns. Their solid state electrical conductivities have been investigated, show _rt in the 10^–10–10^–6 S cm^–1 range, and semiconduct at 313–383 K with band gaps in the 0.28–0.91 eV range. [Co(phen)₃][Pb(SCN)₂(SeCN)₂], exhibits a remarkable increase, i.e. 10⁴ order of magnitude, in conductivity at higher temperature, which reflects a disordered metallic system where charge carriers have difficulty in crossing the non-conducting barrier at low temperature.     

The preparation and molecular structure oftrans-[MoCl2(PMe2Ph)4]

Summary The compoundtrans-[MoCl₂(PMe₂Ph)₄] has been prepared by the reduction of MoCl₅ (by Mg) or of [MoCl₃(PMe₂Ph)₃] (by LiBuⁿ) in the presence of PMe₂Ph in tetrahydrofuran (THF). It has _eff=2.84 B.M. and crystallises in space group P1 witha=11.591(3),b=12.931(3),c=12.703(3) Å, = 95.28(2), =105.97(2), =103.54(2)°. Refinement of the structure gave R=0.036. The Mo-Cl and Mo-P distances average 2.443(6) and 2.534(8) Å, respectively.Low-valent phosphine complexes of the Group VI metals continue to attract much attention because of their involvement in studies of the catalytic activation of dinitrogen⁽¹⁾, dihydrogen(^{2, 3}), alkenes and alkynes(⁴). As a by-product during our studies of dinitrogen(¹) and hydride(²) complexes of molybdenum and tungsten, we obtainedtrans-[MoCl_2- (PMe₂Ph)₄] as yellow, paramagnetic crystals (_eff= 2.84 B.M.). We first obtained the compound during the attempted synthesis ofcis-[Mo(N₂)₂(PMe₂Ph)₄] by reduction of MoCl₅ with Mg in the presence of PMe₂Ph (see Experimental). Upon identification of the compound we found that it could be readily synthesised by treatment of [MoCl₃(PMe₂Ph)₃]⁽⁵⁾ with LiBuⁿ in THF in the presence of PMe₂Ph (experimental).The complex was shown to have thetrans structure by x-ray analysis (Figure). Analogues oftrans-[MoCl₂(PMe₂Ph)₄] have been prepared, namely [CrCl₂(Me₂PCH₂CH₂PMe₂)₂]⁽⁶⁾,trans- [MoCl₂(PMe₃)₄]⁽⁷⁾, [WCl₂(PMe₂Ph)₄]⁽⁸⁾ and [WCl₂(PMe₃)₄]⁽⁴⁾, of which onlytrans-[MoCl₂(PMe₃)₄] has been examined by X-rays⁽⁷⁾. Its principal structural parametersi.e. d(Mo-Cl)= 2.420(6), d(Mo-P)_av=2.496(3) Å⁽⁶⁾ are close to those found here fortrans-[MoCl₂(PMe₂Ph)₄].     

Halogeno-Nitrosylkomplexe von Molybdän und Wolfram. Die Kristallstrukturen von [Na2(15-Krone-5)2(CH3CN)][MoCl4(NO)2] und [Na(15-Krone-5)]2[MoF4Cl(NO)]

Halogeno-Nitrosyl Complexes of Molybdenum and Tungsten. Crystal Structures of [Na₂(15-Crown-5)₂(CH₃CN)][MoCl₄(NO)₂] and [Na(15-Crown-5)]₂[MoF₄Cl(NO)] MoCl₂(NO)₂ and WCl₂(NO)₂, respectively, react with excess sodium fluoride in acetonitrile at room temperature and in the presence of 15-crown-5 to give crystalline mixtures, which consist of the title compounds, respectively of [Na(15-crown-5)]₂[WCl₄(NO)₂] and [Na(15-crown-5)]₂[WF₄Cl(NO)], and which can be separated by selection. The complexes are characterized by their i.r. spectra, the molybdenum compounds additionally by crystal structure determinations. [Na₂(15-crown-5)₂(CH₃CN)][MoCl₄(NO)₂]: Space group P2₁, Z = 2, 5415 independent unique reflexions, R = 0.039. Lattice dimensions at ?10°C: a = 984.3, b = 1231.1, c = 1483.0 pm, β = 105.67°. The compound consists of cations [Ne(l5-crown-5)(CH₃CN)]⁺, in which the sodium ion is surrounded by the five O-atoms of the crown ether and by the N-atom of the acetonitrile molecule, as well as of anions, which form an ion pair {Na(15-crown-5)[MoCl₄(NO)₂]}^?. In the in pairs the sodium ion is coordinated by the five oxygen atoms of the crown ether and by two chlorine atoms of the [MoCI₄(NO)₂]^2? unit. The nitrosyl ligands take the cis-position a t the molybdenum atom which is in a distorted octahedrally fashion. [Na(15-crown-5)]₂[MoF₄Cl(NO)]. Space group C2/c, Z = 4, 1933 independent unique reflexions, R = 0.078. Lattice dimensions at ?7O°C: D : 1.585.8, b = 1171.5, c = 1771.5 pm, β = 114.91°. The compound forms an ion triple, in which the sodium ions are linked to five oxygen atoms each of the crown ether molecules, and to two F-atoms of the [MoF₄Cl(NO)]^2? unit. The F-atom which is arranged in trans-position to the nitrosyl ligand coordinates with both sodium ions; thus an unusual T-shaped arrangement results for this F-atom. The sole terminal F-Atom and the Cl-atom are disordered in two positions.     

Ein- und zweikernige Dinitrosylkomplexe von Molybdän und Wolfram. Die Kristallstrukturen von (PPh3Me)2[WCl4(NO)2], (PPh3Me)2[MoCl3(NO)2]2 und von (PPh3Me)2[WCl3(NO)2]2

Mono- and Binuclear Dinitrosyl Complexes of Molybdenum and Tungsten. Crystal Structures of (PPh₃Me)₂[WCl₄(NO)₂], (PPh₃Me)₂[MoCl₃(NO)₂]₂, and (PPh₃Me)₂[WCl₃(NO)₂]₂ The complexes (PPh₃Me)₂[MCl₄(NO)₂] (M = Mo, W), and (PPh₃Me)₂[MCl₃(NO)₂]₂, respectively, are prepared by reactions of the polymeric compounds MCl₂(NO)₂ with triphenylmethylphosphonium chloride in CH₂Cl₂, forming green crystals. According to the IR spectra the nitrosyl groups are in cis-position in all cases. The tungsten compounds as well as (PPh₃Me)₂[MoCl₃(NO)₂]₂ were characterized by structure determinations with X-ray methods. (PPh₃Me)₂[WCl₄(NO)₂]: space group C2/c, Z = 4. a = 1874, b = 1046, c = 2263 pm, β = 119.99°. Structure determination with 3492 independent reflexions, R = 0.057. The compound consists of PPh₃Me^⊕ ions, and anions [WCl₄(NO)₂]^2? with the nitrosyl groups in cis-position (symmetry C_2v). (PPh₃Me)₂[WCl₃(NO)₂]₂: Space group C2/c, Z = 4. Structure determination with 2947 independent reflexions, R = 0.059. (PPH₃Me)₂[MoCl₃(NO)₂]₂: Space group P1 , Z = 1. a = 989, b = 1134, c = 1186 pm; α = 63.25°, β = 80.69°, γ = 69.94°. Structure determination with 3326 independent reflexions, R = 0.046. The compounds consist of PPh₃Me^⊕ ions, and centrosymmetric anions [MCl₃(NO)₂]₂^2?, in which the metal atoms are associated via MCl₂M bridges of slightly different lengths. One of the NO groups is in an axial position, the other one in equatorial position (symmetry C_2h).     

Structure and in vitro antifungal activity of [2,6‐bis(dimethylaminomethyl)phenyl]diphenyltin(IV) compounds

A set of seven [2,6‐bis(dimethylaminomethyl)phenyl]diphenyltin(IV) ({[(CH₃)₂NCH₂]₂(C₆H₃)}­(C₆H₅)₂Sn⁺X^?) ionic organotin(IV) compounds (X = Br, NO₃, CN, SCN, SeCN, BF₄ and PF₆) has been prepared and characterized by electrospray ionization mass spectrometry, ¹H NMR spectroscopy in CDCl₃,¹¹⁹Sn NMR in CDCl₃ and DMSO‐d₆ solution, as well as by ¹³C and ¹¹⁹Sn CP/MAS NMR spectroscopy and X‐ray diffraction techniques in the solid state. The in vitro antifungal activity of these water‐soluble ionic organotin(IV) compounds was compared with starting compounds and the antifungal drugs currently in clinical use. Copyright © 2002 John Wiley & Sons, Ltd.     

(PPh3Me)2[{MoCl4(NO)}2 (μ-S2N2)]; Synthese,IR-Spektrum und Kristallstruktur

(PPh₃Me)₂[{MoCl₄(NO)}₂(μ-S₂ N₂)]; Synthesis, I.R. Spectrum, and Crystal Structure The title compound is prepared by the reaction of (PPh₃Me)₂[MoCl₃(NO)₂]₂ with trithiazyl chloride in CH₂Cl₂ solution. It forms yellow, only slightly moisture sensitive crystals, which are characterized by their IR spectrum as well as by an X-ray structure determination. (PPh₃Me)₂[{MoCl₄(NO)}₂ (μ-S₂N₂)] crystallizes triclinic in the space group P1 with one formula unit in the unit cell (5952 independent, observed reflexions, R = 0.045). The lattice dimensions are at 20°C: a = 1021, b = 1143, c = 1243, pm; α = 64,15°, β = 68.24°, γ = 80.85°. The compound consists of PPh₃Me⊕ cations and anions [{MoCl₄(NO)}₂(μ-S₂N₂)]²?, in which the molybdenum atoms are bridged by the N-atoms of the planar S₂N₂ ring. In the trans-positions of these N-atoms the linear nitrosyl groups are coordinated via Mo ? N ? O .     

Darstellung von trans-[Pt(N3)4X2]2− (X = Br,I, SCN,SeCN) durch oxidative Addition an [Pt(N3)4]2− in organischen Lösungsmitteln

Preparation of trans-[Pt(N₃)₄X₂]^2? (X ? Br, I, SCN, SeCN) by Oxidative Addition to [Pt(N₃)₄]^2? in Organic Solvents By oxidative addition to (TBA)₂[Pt(N₃)₄], dissolved in dichlormethane, trans-(TBA)₂[Pt(N₃)₄X₂], X ? Br, I, SCN, SeCN; TBA = Tetrabutylammonium, are formed. The vibrational spectra of these salts are assigned according to point group D_4h. From the resonance Raman spectrum of trans-(TBA)₂[Pt(N₃)₄I₂] the harmonic vibrational frequency ω₁ of v(Pt? I), A_1g, is calculated to be 138.50 cm^?1 and the inharmonicity constant x₁₁ = 0.27 cm^?1. The characteristical feature in the UV/VIS spectra is caused by intensive π(N,X) → a_1g, b_1g(Pt) CT transitions.     

A new method of preparation of the anionic decacarbonyls M2(CO)102− (M = Cr,Mo, W) and syntheses and properties of Mg(THF)2[M2(CO)10]

The anionic decacarbonyIs M₂(CO)₁₀^2? were synthesized via reduction reactions of CrCl₃, MoCl₅ and WCl₆ with metallic magnesium or sodium amalgam under carbon monoxide. Chemical properties and IR characteristics of the magnesium salt Mg(THF)₂[M₂(CO)₁₀] are desribed.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von trans‐(n‐Bu4N)2[Pt(ECN)2(ox)2], E = S,Se

Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of trans ‐( n ‐Bu₄N)₄[Pt(ECN)₂(ox)₂], E = S, Se By reaction of (n‐Bu₄N)₂[Pt(ox)₂] with (SCN)₂ and (SeCN)₂ in dichloromethane trans‐(n‐Bu₄N)₂[Pt(SCN)₂(ox)₂] ( 1 ) und trans‐(n‐Bu₄N)₂[Pt(SeCN)₂(ox)₂] ( 2 ) are formed. The crystal structures of 1 (triclinic, space group P1, a = 10.219(2), b = 11.329(2), c = 12.010(3) Å, α = 114.108(15), β = 104.797(20), γ = 102.232(20)°, Z = 1) and 2 (triclinic, space group P1, a = 10.288(1), b = 11.332(1), c = 12.048(1) Å, α = 114.391(9), β = 103.071(10), γ = 102.466(12)°, Z = 1) reveal, that the compounds crystallize isotypically with centrosymmetric complex anions. The bond lengths are Pt–S = 2.357, Pt–Se = 2.480 and Pt–O = 2.011 ( 1 ) und 2.006 Å ( 2 ). The oxalato ligands are nearly plane with O–C–C–O torsion angles of 1.7–3.6°. The via S or Se coordinated linear groups are inclined between both oxalato ligands with Pt–E–C angles of 100.4 (E = S) and 97.4° (Se). In the vibrational spectra the PtE stretching vibrations are observed at 299–314 ( 1 ) and 189–200 cm^–1 ( 2 ). The PtO stretching vibrations are coupled with internal vibrations of the oxalato ligands and appear in the range of 400–800 cm^–1. Based on the molecular parameters of the X‐ray determinations the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are f_d(PtS) = 1.75, f_d(PtSe) = 1.35 and f_d(PtO) = 2.77 mdyn/Å. The NMR shifts are δ(¹⁹⁵Pt) = 5435.2 ( 1 ), 5373.7 ( 2 ) and δ(⁷⁷Se) = 353.2 ppm with the coupling constant ¹J(SePt) = 37.4 Hz.     

Darstellung,Kristallstrukturen und Schwingungsspektren von trans‐[Pt(N3)4(ECN)2]2–, E = S,Se

Synthesis, Crystal Structures, and Vibrational Spectra of trans ‐[Pt(N₃)₄(ECN)₂]^2–, E = S, Se By oxidative addition to (n‐Bu₄N)₂[Pt(N₃)₄] with dirhodane in dichloromethane trans‐(n‐Bu₄N)₂[Pt(N₃)₄(SCN)₂] and by ligand exchange of trans(n‐Bu₄N)₂[Pt(N₃)₄I₂] with Pb(SeCN)₂ trans‐(n‐Bu₄N)₂[Pt(N₃)₄(SeCN)₂] are formed. X‐ray structure determinations on single crystals of trans‐(Ph₄P)₂[Pt(N₃)₄(SCN)₂] (triclinic, space group P 1, a = 10.309(3), b = 11.228(2), c = 11.967(2) Å, α = 87.267(13), β = 75.809(16), γ = 65.312(17)°, Z = 1) and trans‐(Ph₄P)₂[Pt(N₃)₄(SeCN)₂] (triclinic, space group P 1, a = 9.1620(10), b = 10.8520(10), c = 12.455(2) Å, α = 90.817(10), β = 102.172(10), γ = 92.994(9)°, Z = 1) reveal, that the compounds crystallize isotypically with octahedral centrosymmetric complex anions. The bond lengths are Pt–S = 2.337, Pt–Se = 2.490 and Pt–N = 2.083 (S), 2.053 Å (Se). The approximate linear Azidoligands with N^α–N^β–N^γ‐angles = 172,1–175,0° are bonded with Pt–N^α–N^β‐angles = 116,7–120,5°. In the vibrational spectra the platinum chalcogen stretching vibrations of trans‐(n‐Bu₄N)₂[Pt(N₃)₄(ECN)₂] are observed at 296 (E = S) and in the range of 186–203 cm^–1 (Se). The platinum azide stretching modes of the complex salts are in the range of 402–425 cm^–1. Based on the molecular parameters of the X‐ray determinations the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are f_d(PtS) = 1.64, f_d(PtSe) = 1.36, f_d(PtN^α) = 2.33 (S), 2.40 (Se) and f_d(N^αN^β, N^βN^γ) = 12.43 (S), 12.40 mdyn/Å (Se).     

Diphenyl-diacetylen-Komplexe von Molybdän(IV) und Wolfram(IV). Die Kristallstrukturen von PPh4[WCl5(Ph?CC?CC?Ph)] · CCI4 und von PPh4[WCl5(Ph?CC?C(Br)C(Br)?Ph)] · CCl4

Diphenyldiacetylene Complexes of Molybdenum (IV) and Tungsten (IV). Crystal Structures of PPh₄[WCl₅(Ph? C?C? C?C? Ph)] · CCl₄ and PPh₄[WCl₅(Ph? C?C? C(Br)?C(Br)? Ph)] · CCl₄ Syntheses and i.r. spectra of the following diphenyldiacetylene complexes are reported: [MoCl₄(Ph? C?C? C?C? Ph)]₂( 1 ), [WCl₄(Ph? C?C? C?C? Ph)]₂ ( 2 ), PPh₄[WCl₅(Ph? C?C? C?C? Ph)] · CCl₄ ( 3 ). 1 is formed in the reaction of MoCl₅ with excess diphenyldiacetylene. 2 is prepared from WCl₆ and excess diphenylacetylene with additional C₂Cl₄ as a reducing agent. Reaction of 2 with PPh₄Cl in CH₂Cl₂ solution in the presence of CCl₄ yields 3 . The complexes contain one of the acetylene functions bonded in a metallacyclopropene ring; the metal atoms are seven-coordinated. 2 reacts with bromine to from the dibromide [WCl₄(Ph? C?C? C(Br)? Ph)]₂ (4). In CH₂Cl₂ solution and in presence of ccl₄ 4 is turned into the ionic complex PPh₄[Ph? C?C? C(Br)? Ph] · CCl₄ (5) by PPh₄Cl. The complexes 3 and 5 are characterized by structural analyses on the basis of X-Ray diffraction data. 3 crystallized monoclinic in the space group p2₁/n with four formula units per unit cell (2623 observed, independent reflexions, R = 5.4%). 5 crystallized in the same space group, set P2₁/c, the unit cell containing four formula units (2537 observed, independent reflexions, R = 5.4%). Both complexes consist of tetraphenylphosphonium cations and anions, in which the tungsten atoms are coordinated by five chlorine and two carbon atoms, the latter bonding side-on, in an approximately symmetrical way. In addition the lattices contain one molecule CCl₄ per formula unit. The acetylene ligand causes a strong trans-effect. As a result the W? Cl bond lengths in trans-position are by 10 pm longer than those in cis-position. Bromination of the second acetylene function of 3 leads to addition in trans-position (5).     

Reactions of molybdenum(III) with macrocyclic polythiaethers

Reactions of MoCl₃(THF)₃ and MoCl₃(PrCN)₃ with the macrocyclic polythiaethers: 1,4,8,11-tetrathiacyclotetradecane (TTP) and 1,4,7,10,13,16-hexathiacyclooctadecane (HTO) were studied. The type of reaction and the complexes formed depend on reactant concentration and nature of the solvent. The complexes: [MoCl₃(HTO)], [(MoCl₃)₂(HTO)(THF)₃], [MoCl₃(TTP)(THF)] and [MoCl₃(TTP)] in which the macrocyclic polythiaethers are coordinated to the molybdenum through sulphur atoms were isolated. Some new mixed-valence complexes were formed in reactions where a partial change in the molybdenum oxidation state and a cleavage of the macrocyclic ring took place. The following complexes were isolated: [Mo₃Cl₉(PHT)₂(PrCN)]·CH₂Cl₂, [Mo₃Cl₉(PHT)₂(THF)] · CH₂Cl₂, [Mo₂Cl₆ (PHT)] · CH₂Cl₂, [Mo₃Cl₉(TTT)₂(THF)] · CH₂Cl₂, where PHT = 3,6,9,12,15-pentathiaheptadec- 16-ene-1-thiolato(1-) and TTT = 4,7,11-trithiatridec-12-ene-1-thiolato(1-). The complexes were characterized on the basis of elemental analyses, magnetic measurements, IR, ¹H NMR, ¹³C NMR and mass spectra.     

Two Mercury Chloro Thiocyanate Complexes: NH4[HgCl2(SCN)] and NH4[HgCl(SCN)2]

Single crystals of NH₄[HgCl₂(SCN)] ( 1 ) and NH₄[HgCl(SCN)₂] ( 2 ) are obtained by slow evaporation of ethanol solutions of HgCl₂ and NH₄SCN or Hg(SCN)₂ and NH₄Cl. 1 crystallizes in the monoclinic space group P2₁ (a = 9.297(1), b = 4.171(1), c = 9.198(1)Å, β = 92.827(5)°). The structure consists in HgCl₂(SCN) linear chains, extending along the twofold axis, connected through the ammonium ions. 2 crystallizes in the monoclinic space group C2/c (a = 7.088(1), b = 19.986(2), c = 5.958(1)Å, β = 100.718(5)°). The structure consists of HgCl(SCN)₂ molecules connected through the ammonium ions. The second order non linear optical properties of 1 are discussed.     

Preparation of Pseudohalidoheptasulfur(+1) Hexafluorometallates S7X+MF−6 (X = CN,OCN, SeCN; M = As,Sb)

The preparation and spectroscopic characterization of S₇X⁺MF^?₆ (X = CN, OCN, SCN, SeCN; M = As, Sb) is reported. The new compounds are formed in analogy to the preparation of halidocycloheptrasulfur(+1) cations from S²⁺₈(MF^?₆)₂ and alkali pseudohalides in So₂ as solvent. Their thermal stabilities decrease with the increasing Pearson hardness of the pseudohalide ligands.