Gold(I) and Silver(I) Complexes with Thioether Functionalized Silylamido Ligands

The thioether functionalized aminosilanes Me₂Si(NH‐C₆H₄‐2‐SR)₂ (R = Ph, Me) were lithiated with nBuLi and subsequently reacted with AgCl in the presence of PMe₃ or with [AuCl(PMe₃)]. In the case of Me₂Si(NH‐C₆H₄‐2‐SPh)₂ the dinuclear complexes [M₂{Me₂Si(NC₆H₄‐2‐SPh)₂}(PMe₃)₂] (M = Ag; Au) were isolated. The analogous reactions starting from Me₂Si(NH‐C₆H₄‐SMe)₂ afforded the dinuclear gold complex [Au₂{Me₂Si(NC₆H₄‐2‐SMe)₂}(PMe₃)₂] and the tetranuclear silver complex [Ag₄{Me₂Si(NC₆H₄‐2‐SMe)₂}₂(PMe₃)₂]. In the dinuclear compounds of the type [M₂{Me₂Si(NC₆H₄‐2‐SR)₂}(PMe₃)₂], each of the silylamide N atoms is connected to a M(PMe₃) group to give a nearly linear N–M–P arrangement with Ag–N and Au–N bonds in the range of 212.0(4)–213.3(4) pm and 205.3(3)–208.1(9) pm, respectively. [Ag₄{Me₂Si(NC₆H₄‐2‐SMe)₂}₂(PMe₃)₂] consists of a central Si₂N₄Ag₂ ring with linearly coordinated Ag atoms (Ag‐N: 223.1(4)–222.1(4) pm) and two peripheral Ag(PMe₃) units, which are connected to the amido N atoms in a chelating mode. The relatively short transannular Ag ··· Ag separation (277.6(1) pm) within the Si₂N₄Ag₂ ring hints for argentophilic interactions. The peripheral Ag atoms are three coordinated with Ag–N distances of 233.9(4)–242.8(4) pm.     

Experimental and Theoretical Studies on Arene‐Bridged Metal–Metal‐Bonded Dimolybdenum Complexes

The bis(hydride) dimolybdenum complex, [Mo₂(H)₂{HC(N‐2,6‐iPr₂C₆H₃)₂}₂(thf)₂], 2 , which possesses a quadruply bonded Mo₂^II core, undergoes light‐induced (365 nm) reductive elimination of H₂ and arene coordination in benzene and toluene solutions, with formation of the Mo^I₂ complexes [Mo₂{HC(N‐2,6‐iPr₂C₆H₃)₂}₂(arene)], 3?C₆H₆ and 3?C₆H₅Me , respectively. The analogous C₆H₅OMe, p‐C₆H₄Me₂, C₆H₅F, and p‐C₆H₄F₂ derivatives have also been prepared by thermal or photochemical methods, which nevertheless employ different Mo₂ complex precursors. X‐ray crystallography and solution NMR studies demonstrate that the molecule of the arene bridges the molybdenum atoms of the Mo^I₂ core, coordinating to each in an η² fashion. In solution, the arene rotates fast on the NMR timescale around the Mo₂‐arene axis. For the substituted aromatic hydrocarbons, the NMR data are consistent with the existence of a major rotamer in which the metal atoms are coordinated to the more electron‐rich C?C bonds.     

Synthesis and Crystal Structure of a Tetranuclear Molybdenum(II) Silylamido Cluster

Treatment of molybdenum(II) chloride with the difunctional silylamide Li₂Me₂Si(NPh)₂ led to the formation of the tetranuclear cluster compound [Mo₄{Me₂Si(NPh)₂}₄]. According to the X-ray crystal structure determination, the central core of the cluster consists of four molybdenum atoms in a nearly rectangular arrangement. There are two μ₄-κ-N,N,N',N'-Me₂Si(NPh)₂^2– ligands capping the Mo₄ rectangle and two μ₂-Me₂Si(NPh)₂^2– ligands located at opposite edges. The alternating Mo–Mo distances of 218.1(1) and 279.5(1) pm indicate the presence of a cyclobutadiyne type cluster with alternating Mo–Mo triple and single bonds.     

Transition‐Metal‐Mediated Cleavage of Fluoro‐Silanes under Mild Conditions

Si?F bond cleavage of fluoro‐silanes was achieved by transition‐metal complexes under mild and neutral conditions. The Iridium‐hydride complex [Ir(H)(CO)(PPh₃)₃] was found to readily break the Si?F bond of the diphosphine‐ difluorosilane {(o‐Ph₂P)C₆H₄}₂Si(F)₂ to afford a silyl complex [{[o‐(iPh₂P)C₆H₄]₂(F)Si}Ir(CO)(PPh₃)] and HF. Density functional theory calculations disclose a reaction mechanism in which a hypervalent silicon species with a dative Ir→Si interaction plays a crucial role. The Ir→Si interaction changes the character of the H on the Ir from hydridic to protic, and makes the F on Si more anionic, leading to the formation of H^δ+???F^δ? interaction. Then the Si?F and Ir?H bonds are readily broken to afford the silyl complex and HF through σ‐bond metathesis. Furthermore, the analogous rhodium complex [Rh(H)(CO)(PPh₃)₃] was found to promote the cleavage of the Si?F bond of the triphosphine‐monofluorosilane {(o‐Ph₂P)C₆H₄}₃Si(F) even at ambient temperature.     

Heterobimetallic complexes of palladium(II) bridged by the mixed phosphine–phosphine oxide ligand Ph2PCH2CH2P(O)Ph2

The mixed phosphine–phosphine oxide Ph₂PCH₂CH₂P(O)Ph₂ (dppeO) reacts with either trans-[PdCl₂(PhCN)₂], Na₂[PdCl₄] or trans-[PdCl₂(DMSO)₂] to give trans-[PdCl₂{¹-Ph₂PCH₂CH₂P(O)Ph₂}₂]. Treatment of the latter with the metal chlorides, MCl₂ · nH₂O (M = Mn, Cu, Co, Zn, Hg; n = 4, 2, 6, 1, 0, respectively) or with Me₂SnCl₂ or SnCl₄ · 5H₂O, or with UO₂(NO₃)₂ · 6H₂O or UO₂(OAc)₂ · 2H₂O gives heterobimetallic complexes: trans-[PdCl₂{-Ph₂PCH₂CH₂P(O)Ph₂}₂MX₂] · nH₂O. The cobalt complex (MX₂ = CoCl₂) was unstable in solution (MeOH or EtOH/CHCl₃), and reverts to trans-[PdCl₂{¹-Ph₂PCH₂CH₂P(O)Ph₂}₂] and CoCl₂. trans-[PdCl₂{¹-Ph₂PCH₂CH₂P(O)Ph₂}₂] does not apparently react with either NiCl₂ · 6H₂O or CdCl₂ · 2.5H₂O.     

Synthesis,Structure and Characterization of Dinuclear Pentacoordinate Molybdenum(V) Complexes with Thiosemicarbazone Ligands

New dinuclear pentacoordinate molybdenum(V) complexes, [Mo₂^VO₃L₂] [L = thiosemicarbazonato ligand: C₆H₄(O)CH:NN:C(S)NHR′ and C₁₀H₆(O)CH:NN:C(S)NHR′; R′ = H, CH₃, C₆H₅) were obtained either by oxygen atom abstraction from Mo^VIO₂L with triphenylphosphine or by using [Mo₂O₃(acac)₄] in the reaction with the corresponding ligands H₂L. Crystal and molecular structure of [Mo₂O₃{C₆H₄(O)CH:NN:C(S)NHC₆H₅}₂] · CH₃CN has been determined by the single‐crystal X‐ray diffraction method.     

Koordinativ ungesättigte Eisen-Chalkogenolat-Komplexe mit trigonalplanaren Ligandensphären – Synthese,Eigenschaften und Reaktionen mit Stickstoff- und Sauerstoff-Donormolekülen

Coordinatively Unsaturated Iron Chalcogenolate Complexes with Trigonal Planar Ligand Spheres – Synthesis, Properties, and Reactions with Nitrogen and Oxygen Donor Molecules The new bulky organo-selenium compound 2,4,6-triphenylbenzeneselenole ( 1 A ) was synthesized by a multistep-reaction from 1,3,5-triphenylbenzene. 1 A was converted by oxidation into the air-stable bis(2,4,6-triphenylphenyl)diselenide ( 1 B ), which was characterized by X-ray diffraction. The stepwise reaction of [Fe₂{N(SiMe₃)₂}₄] with 1 A leads to the complexes [Fe₂(SeC₆H₂-2,4,6-Ph₃)₂{N(SiMe₃)₂}₂] ( 2 ) and [Fe₂(SeC₆H₂-2,4,6-Ph₃)₄] ( 3 ), controlled by their molar ratios. The conversion of 2 to 3 is also described. In addition, the coordinatively unsaturated thiolate complexes [Fe₂{SC₆H₃-2,6-(SiMe₃)₂}₂{N(SiMe₃)₂}₂] ( 4 ) and [Fe₂{SC₆H₃-2,6-(SiMe₃)₂}₄] ( 5 ) were synthesized by stepwise reaction of [Fe₂{N(SiMe₃)₂}₄] with 2,6-bis(trimethylsilyl)benzenethiole. It is also possible to convert the heteroleptic compound 4 into the homoleptic thiolate complex 5 . During our investigations of the reactivity of 5 towards small electroneutral molecules, the compounds [Fe₂{SC₆H₃-2,6-(SiMe₃)₂}₄ · (MeCN)₂] ( 6 ) and [Fe{SC₆H₃-2,6-(SiMe₃)₂}₂(OPEt₃)] ( 7 ) were obtained. 6 is the product of the addition of two molecules of acetonitrile to 5 . The iron atoms of 6 are coordinated by three sulfur and one nitrogen atom in a distorted tetrahedral manner. When 5 is treated with triethylphosphine oxide instead of acetonitrile, the mononuclear complex 7 with the coordination number three is formed. The iron atom is surrounded by two sulfur and one oxygen donor functions.     

Aliphatic Organoimido Derivatives of Polyoxometalates Containing a Bioactive Ligand

A series of aliphatic organoimido derivatives of hexamolybdate based on amantadine, namely (nBu₄N)₂[Mo₆O₁₈(?NC₁₀H₁₅)] ( 1 ), (nBu₄N)₂ {cis‐[Mo₆O₁₇(?NC₁₀H₁₅)₂]} ( 2 ), (nBu₄N)₂{trans‐[Mo₆O₁₇(?NC₁₀H₁₅)₂]} ( 3 ), and (nBu₄N)₂[Mo₆O₁₆(?NC₁₀H₁₅)₃] ( 4 ), was synthesized in reasonable yield by dehydration with N,N′‐dicyclohexylcarbodiimide (DCC). They were characterized by IR and UV/Vis spectroscopy, elemental analysis, ESI mass spectrometry, and single‐crystal X‐ray structure analysis. The spectral and structural similarities and differences between monosubstituted, cis‐disubstituted, and trans‐disubstituted organoimido derivatives were elucidated and may provide guidance for related work on organoimido‐functionalized Lindqvist‐type polyoxometalates. In addition, trans‐disubstituted and polysubstituted derivatives containing aliphatic organoimido ligands have not yet been reported, and the crystal structure of the trans isomer may lead us to a deeper understanding of disubstituted derivatives. Furthermore, proliferation and morphology of MCF‐7 cells were studied with compound 1 . The present results show that the DCC‐dehydrating protocol could be an efficient approach to covalently graft bioactive ligands such as amantadine onto POMs and enhance their application in clinical cancer treatment.     

Accessing Cationic α-Silylated and α-Germylated Phosphorus Ylides

The synthesis and full characterization of α-silylated (α-SiCPs; 1 – 7 ) and α-germylated (α-GeCPs; 11 – 13 ) phosphorus ylides bearing one chloride substituent R₃PC(R¹)E(Cl)R²₂ (R=Ph; R¹=Me, Et, Ph; R²=Me, Et, iPr, Mes; E=Si, Ge) is presented. The molecular structures were determined by X-ray diffraction studies. The title compounds were applied in halide abstraction studies in order to access cationic species. The reaction of Ph₃PC(Me)Si(Cl)Me₂ ( 1 ) with Na[B(C₆F₅)₄] furnished the dimeric phosphonium-like dication [Ph₃PC(Me)SiMe₂]₂[B(C₆F₅)₄]₂ ( 8 ). The highly reactive, mesityl- or iPr-substituted cationic species [Ph₃PC(Me)SiMes₂][B(C₆F₅)₄] ( 9 ) and [Ph₃PC(Et)SiiPr₂][B(C₆F₅)₄] ( 10 ) could be characterized by NMR spectroscopy. Carrying out the halide abstraction reaction in the sterically demanding ether iPr₂O afforded the protonated α-SiCP [Ph₃PCH(Et)Si(Cl)iPr₂][B(C₆F₅)₄] ( 6 dec ) by sodium-mediated basic ether decomposition, whereas successfully synthesized [Ph₃PC(Et)SiiPr₂][B(C₆F₅)₄] ( 10 ) readily cleaves the F−C bond in fluorobenzene. Thus, the ambiphilic character of α-SiCPs is clearly demonstrated. The less reactive germanium analogue [Ph₃PC(Me)GeMes₂][B{3,5-(CF₃)₂C₆H₃}₄] ( 14 ) was obtained by treating 11 with Na[B{3,5-(CF₃)₂C₆H₃}₄] and fully characterized including by X-ray diffraction analysis. Structural parameters indicate a strong C_Ylide−Ge interaction with high double bond character, and consequently the C−E (E=Si, Ge) bonds in 9 , 10 and 14 were analyzed with NBO and AIM methods.     

On the Reactivity of Silylated Ge9 Clusters: Synthesis and Characterization of [ZnCp*(Ge9{Si(SiMe3)3}3)], [CuPiPr3(Ge9{Si(SiMe3)3}3)], and [(CuPiPr3)4{Ge9(SiPh3)2}2]

We report on the synthesis of new derivatives of silylated clusters of the type [Ge₉(SiR₃)₃]^? (R = SiMe₃, Me = CH₃; R = Ph, Ph = C₆H₅) as well as on their reactivity towards copper and zinc compounds. The silylated cluster compounds were synthesized by heterogeneous reactions starting from the Zintl phase K₄Ge₉. Reaction of K[Ge₉{Si(SiMe₃)₃}₃] with ZnCl₂ leads to the already known dimeric compound [Zn(Ge₉{Si(SiMe₃)₃}₃)₂] ( 1 ), whereas upon the reaction with [ZnCp*₂] the coordination of [ZnCp*]⁺ to the cluster takes place (Cp*=1,2,3,4,5‐pentamethylcyclopentadienyl) under the formation of [ZnCp*(Ge₉{Si(SiMe₃)₃}₃)] ( 2 ). A similar reaction leads to [CuPiPr₃(Ge₉{Si(SiMe₃)₃}₃)] ( 3 ) from [CuPiPr₃Cl] (iPr=isopropyl). Further we investigated the novel silylated cluster units [Ge₉(SiPh₃)₃]^? ( 4 ) and [Ge₉(SiPh₃)₂]^? ( 5 ), which could be identified by mass spectroscopy. Bis‐ and tris‐silylated species can be synthesized by the respective stoichiometric reactions, and the products were characterized by ESI‐MS and NMR experiments. These clusters show rather different reactivity. The reaction of the tris‐silylated anion 4 with [CuPiPr₃Cl] leads to [(CuPiPr₃)₃Ge₉(SiPh₃)₂]⁺ as shown from NMR experiments and to [(CuPiPr₃)₄{Ge₉(SiPh₃)₂}₂] ( 6 ), which was characterized by single‐crystal X‐ray diffraction. Compound 6 shows a new type of coordination of the Cu atoms to the silylated Zintl clusters.     

Three 1-D molybdenum(V) phosphates with copper/nickel coordination cations

Three 1-D reduced molybdenum(V) phosphates, [Ni(OH)₂][Na₂(H₂O)₃]₂{Ni[(MoO₂)₆(OH)₃(HPO₄)₃(PO₄)]₂}?·?2C₆H₁₄N₂?·?2H₃O?·?5H₂O (1), [Ni(H₂O)₂][K(H₂O)₅]₂{Ni[(MoO₂)₆(OH)₃(HPO₄)₃(PO₄)]₂}?·?2C₆H₁₄N₂?·?2H₃O?·?4H₂O (2), and [Cu(H₂O)₂][Na(H₂O)₅]₂{Cu[(MoO₂)₆(OH)₃(HPO₄)₃(PO₄)]₂}?·?2C₆H₁₄N₂?·?2H₃O?·?4H₂O (3), have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The crystallographic analysis reveals that 1 is based on {Ni[Mo₆O₁₂(OH)₃(HPO₄)₃(PO₄)]₂} clusters connected through {[Ni(OH)₂][Na₂(H₂O)₃]₂} pentanuclear mixed-metal cluster units to yield unusual 1-D chains along the c-axis, which further form 3-D supramolecular networks via hydrogen-bonding. Compounds 2 and 3 are heterogeneous isostructural compounds. Both are built from M[Mo₆P₄]₂ (M?=?Ni or Cu) blocks as the structural motif combined with [MO₄(H₂O)₂] (M?=?Ni or Cu) octahedra to form 1-D chains, where M[Mo₆P₄]₂ (M?=?Ni or Cu) is bonded by [M′(H₂O)₅] (M′?=?K or Na). Furthermore, bulk carbon paste electrode modified with 1 (1-CPE) displays good electrocatalytic activity toward reduction of nitrite or bromate.     

Platinum,iridium and rhodium complexes with substituted bis-(diphenylphosphino)methane ligands Ph2PCH(R)PPh2 (R = Me,Ph or SiMe3)

Substituted phosphines of the type Ph₂PCH(R)PPh₂ and their Pt^II complexes [PtX₂{Ph₂PCH(R)PPh₂}] (R = Me, Ph or SiMe₃; X = halide) were prepared. Treatment of [PtCl₂(NCBu^t)₂] with Ph₂PCH(SiMe₃)-PPh₂ gave [PtCl₂(Ph₂PCH₂PPh₂)], while treatment with Ph₂PCH(Ph)PPh₂ gave [Pt{Ph₂PCH(Ph)PPh₂}₂]Cl₂. Reaction of p-MeC₆H₄C≡CLi or PhC≡CLi with [PtX₂{Ph₂PCH(Me)PPh₂}] gave [Pt(C≡CC₆H₄Me-p)₂-{Ph₂PCH(Me)PPh₂}] (X = I) and [Pt{Ph₂PC(Me)PPh₂}₂](X = Cl),while reaction of p-MeC₆H₄C≡CLi with [Pt{Ph₂PCH(Ph)PPh₂}₂]Cl₂ gave [Pt{Ph₂PC(Ph)PPh₂}₂]. The platinum complexes [PtMe₂(dpmMe)] or [Pt(CH₂)₄(dpmMe)] fail to undergo ring-opening on treatment with one equivalent of dpmMe [dpmMe = Ph₂PCH(Me)PPh₂]. Treatment of [Ir(CO)Cl(PPh₃)₂] with two equivalents of dpmMe gave [Ir(CO)(dpmMe)₂]Cl. The PF₆ salt was also prepared. Treatment of [Ir(CO)(dpmMe)₂]Cl with [Cu(C≡CPh)₂], [AgCl(PPh₃)] or [AuCl(PPh₃)] failed to give heterobimetallic complexes. Attempts to prepare the dinuclear rhodium complex [Rh₂(CO)₃(μ-Cl)(dpmMe)₂]BPh₄ using a procedure similar to that employed for an analogous dpm (dpm = Ph₂PCH₂PPh₂) complex were unsuccessful. Instead, the mononuclear complex [Rh(CO)(dpmMe)₂]BPh₄ was obtained. The corresponding chloride and PF₆ salts were also prepared. Attempts to prepare [Rh(CO)(dpmMe)₂]Cl in CHCl₃ gave [RhHCl(dpmMe)₂]Cl. Recrystallization of [Rh(CO)(dpmMe)₂]BPh₄ from CHCl₃/EtOH gave [RhO₂(dpmMe)₂]BPh₄. Treatment of [Rh(CO)₂Cl₂]₂ with one equivalent of dpmMe per Rh atom gave two compounds, [Rh(CO)(dpmMe)₂]Cl and a dinuclear complex that undergoes exchange at room temperature between two formulae: [Rh₂(CO)₂(μ-Cl)(μ-CO)(dpmMe)₂]Cl and [Rh₂(CO)₂-(μ-Cl)(dpmMe)₂]Cl. This revised version was published online in June 2006 with corrections to the Cover Date.     

Reactions of IrHCl2(PPh3)2{P(OEt)3} with Organic Azides: Formation of Aminophosphonium Salts

Aminophosphonium salts [Ph₃PN(H)R]BPh₄ ( 1 ) [R = C₆H₅CH₂ ( 1a ), 4‐CH₃C₆H₄CH₂ ( 1b ), C₆H₅ ( 1c )] were obtained by allowing hydride IrHCl₂(PPh₃)₂{P(OEt)₃} to react first with triflic acid and then with the organic azide RN₃. The compounds were characterized spectroscopically and by X‐ray crystal structure determination of [Ph₃PN(H)CH₂C₆H₄‐4‐CH₃]BPh₄ ( 1b ). A reaction path for the formation of aminophosphonium cations is also proposed.     

Novel Three-Dimensional Coordination Polymers Based on [Mo6Se8(CN)6]7− Anions and Mn2+ Cations

Three novel coordination polymers K₅[MnMo₆Se₈(CN)₆] · 8H₂O (1), (Me₄N)₄[{Mn(H₂O)₂}_1.5Mo₆Se₈(CN)₆] · 4H₂O (2), and K₃[{Mn₂(H₂O)₄}Mo₆Se₈(CN)₆] · 7H₂O (3) have been synthesized by layering of a methanol solution of [Mn(salen)]CH₃COO (salen–N,N′-bis(salicylidene)ethylenediamine) on an aqueous solution of K₇[Mo₆Se₈(CN)₆] · 8H₂O. The compounds have been characterized by single-crystal X-ray diffraction analysis. All structures are based on negatively charged porous polymer frameworks where CN groups of [Mo₆Se₈(CN)₆]⁷⁻ cluster complexes are coordinated to Mn²⁺ cations. Cavities in the frameworks are filled by additional cations and solvate water molecules.     

Zweikern-Komplexe des Wolframs und Molybdäns mit zentraler {XMS2 MX}2+-Einheit (X=O,S) und S 2 2− -bzw. S 4 2− -Liganden

The synthesis and crystal structures of the compounds [PPh ₄]₂[W₂S₁₂]·0.5DMF, [PPh ₄]₂[W₂O₂S₁₀]·0.5DMF, [PPh ₄]₂[W₂S₁₀]··0.5DMF, [PPh ₄][NEt ₄][Mo₂OS₇]·CH₃CN, and [PPh ₄]₂[Mo₂O₂S₁₀] are reported.

     

Organic‐Inorganic Hybrid Supramolecular Assemblies Based on Isomers [HxAs2Mo6O26](6–x)– Clusters

The arsenomolybdates [H₂As₂Mo₆O₂₆(H₂O)] · (H₂biyb)₂ · 2H₂O ( 1 ) and [H₃As₂Mo₆O₂₆] · (H₃pt)₂ ( 2 ) [biyb = 1,4‐bis(imidazol‐1‐ylmethyl)benzene, pt = 4′‐(3′′‐pyridyl)‐2,3′:6′3′′‐terpyridine] were synthesized via hydrothermal method. The structures of the compounds were characterized by single‐crystal X‐ray diffraction analyses, elemental analyses, IR spectroscopy, and TG analysis. Compounds 1 and 2 exhibit two isomeric forms of [H_xAs₂Mo₆O₂₆]^(6–x)–. The structure of 1 is constructed from the B‐type [H₂As₂Mo₆O₂₆(H₂O)]^4– polyanions and free biyb ligands via weak interactions to form 3D supramolecular framework with a {3 · 4 · 5³ · 6}{3 · 4³ · 5²}{3 · 5 · 6}²{3 · 5²}² topology structure. In compound 2 , the A‐type [H₃As₂Mo₆O₂₆]^3– clusters are surrounded by pt ligands through hydrogen bond interactions forming 3D supramolecular framework with a {4³ · 6³}²{4⁶ · 6⁶ · 8³} topology structure. The electrochemical behaviors, electrocatalytic and photocatalytic activities of 1 and 2 are detected.     

Reactions of iridium and platinum complexes with N-sulfinyl compounds

The reactions of substituted N-sulfinylanilines with the complexes {Pt[P(C₆H₅₃]₂O₂} and {IrClCO[P(C₆H₅)₃]₂} have been reinvestigated. The former complex yields {Pt[P(C₆H₅)₃]₂SO₄} as the only isolable product in reactions with N-sulfinylaniline. In contrast to a previous report, Vaska's complex has been found not to react with C₆H₅NSO under anhydrous conditions. {Pt[P(C₆H₅)₃]₂-(C₂H₄)} reacts with N-sulfinyl compounds to give complexes of formula {Pt[P(C₆H₅)₃]₂-(RNSO)} where R = C₆H₅, p-O₂NC₆H₄, p-CH₃C₆H₄, or p-CH₃C₆H₄SO₂. {Pt[P(C₆H₅)₃]₃} reacts with C₆H₅NSO to give the same product obtained from reaction with the ethylene complex. Vaska's complex and its bromo analog form 1:1 adducts with p-O₂NC₆H₄NSO.     

Mesoionic Dithiolates (MIDts) Derived from 1,3-Imidazole-Based Anionic Dicarbenes (ADCs)

Mesoionic dithiolates [(MIDt^Ar)Li(LiBr)₂(THF)₃] (MIDt^Ar={SC(NDipp)}₂CAr; Dipp=2,6-iPr₂C₆H₃; Ar=Ph 3 a , 3-MeC₆H₄ (3-Tol) 3 b , 4-Me₂NC₆H₄ (DMP) 3 c ) and [(MIDt^Ph)Li(THF)₂] ( 4 ) are readily accessible (in≥90 % yields) as crystalline solids on treatments of anionic dicarbenes Li(ADC^Ar) ( 2 a - c ) (ADC^Ar={C(NDipp)₂}₂CAr) with elemental sulfur. 3 a - c and 4 are monoanionic ditopic ligands with both the sulfur atoms formally negatively charged, while the 1,3-imidazole unit bears a formal positive charge. Treatment of 4 with (L)GeCl₂ (L=1,4-dioxane) affords the germylene (MIDt^Ph)GeCl ( 5 ) featuring a three-coordinated Ge atom. 5 reacts with (L)GeCl₂ to give the Ge−Ge catenation product (MIDt^Ph)GeGeCl₃ ( 6 ). KC₈ reduction of 5 yields the homoleptic germylene (MIDt^Ph)₂Ge ( 7 ). Compounds 3 a - c and 4 – 7 have been characterized by spectroscopic studies and single-crystal X-ray diffraction. The electronic structures of 4 – 7 have been analyzed by DFT calculations.     

Syntheses,structures and catalytic properties of new mononuclear terpyridine-manganese(II) complexes with tetraphenylimido-diphosphinate and diphenylphosphinate ligands

Treatment of manganese(II) acetate tetrahydrate [Mn(CH3COO)₂·4H₂O] with one equivalent of 2,2′:6′,2′′-terpyridine (terpy) and two equivalents of potassium tetraphenylimido-diphosphinate K[N(Ph₂PO)₂] in methanol afforded a mononuclear manganese(II) complex, [(terpy)Mn{η¹-O-N(Ph₂PO)₂}₂(H₂O)] (1), with two terminal [N(Ph₂PO)₂]– ligands. Interaction of [Mn(CH₃COO)₂·4H₂O] with one equivalent of terpy in the presence of both K[N(Ph₂PO)₂] and Ph₂PO₂K in methanol gave a mononuclear manganese(II) complex [(terpy)Mn(η¹-O-O₂PPh₂){N(Ph₂PO)₂}] (2) with a chelated [N(Ph₂PO)₂]– ligand. Treatment of manganese(II) dichloride tetrahydrate [MnCl₂·4H₂O] with three equivalents of K[N(Ph₂PO)₂] in methanol resulted in isolation of a mononuclear manganese(III) complex [Mn{η¹-O-N(Ph₂PO)₂}-{N(Ph₂PO)₂}₂] (3) with one terminal and two chelated [N(Ph₂PO)₂]– ligands. Reaction of [Mn(CH₃COO)₂·4H₂O] with one equivalent of 4′-phenyl-[2,2′:6′,2′′]-terpyridine (4-Ph-terpy) and two equivalents of Ph₂PO₂K in methanol gave [(4-Ph-terpy)Mn(η¹-O-O₂PPh₂)₂(H₂O)] (4) with a labile water molecule. Complexes 1–4 have been spectroscopically characterized and their structures have been established by single-crystal X-ray diffraction. Catalytic behavior of 1 and 4 for sulfide oxidation was also investigated.     

The in vitro antifungal activity of some dithiocarbamate organotin(IV) compounds on Candida albicans— a model for biological interaction of organotin complexes

The in vitro antifungal activity of the dithiocarbamate organotin complexes [Sn{S₂CN(CH₂)₄}₂Cl₂] ( 1 ), [Sn{S₂CN(CH₂)₄}₂Ph₂] ( 2 ), [Sn{S₂CN(CH₂)₄}Ph₃] ( 3 ), [Sn{S₂CN(CH₂)₄}₂n‐Bu₂] ( 4 ), [Sn{S₂CN(CH₂)₄}Cy₃] {Cy = cyclohexyl} ( 5 ), [Sn{S₂CN(C₂H₅)₂}₂Cl₂] ( 6 ), [Sn{S₂CN(C₂H₅)₂}₂Ph₂] ( 7 ), [Sn{S₂CN(C₂H₅)₂}Ph₃] ( 8 ), [Sn{S₂CN(C₂H₅)₂}₃Ph] ( 9 ) and [Sn{S₂CN(C₂H₅)₂}Cy₃] ( 10 ) has been screened against Candida albicans (ATCC 18804), Candida tropicalis (ATCC 750) and resistant Candida albicans collected from HIV‐positive Brazilian patients with oral candidiasis. All compounds exhibited antifungal activities and complexes 3 and 8 displayed the best results. We have investigated the effect of compounds 1–10 on the cellular activity of the yeast cultures. Changes in mitochondrial function have not been detected. However, all drugs reduced ergosterol biosynthesis. Preliminary studies on DNA integrity indicated that the compounds do not cause gross damage to yeast DNA. The data suggest that these compounds share some mechanisms of action on cell membranes similar to that of polyene but not with azole drugs, normally used in Candida infections. Copyright © 2008 John Wiley & Sons, Ltd.