ChemInform Abstract: Stability of B12(CN)122‐: Implications for Lithium and Magnesium Ion Batteries.

DFT calculations are used to calculate the binding energies of the second electron of the closo‐borane B₁₂H₁₂^2‐ and B₁₂(CN)₁₂^2‐.     

Synthesis,Crystal Structure and Magnetic Properties of a 1‐D Polymer, [Cu(NITpPy)2(H2TCB)(H20)]·2H2O

A novel complex [Cu(NnpPy)₂(H_lTCB)(H₁O)]·2H₂O (NITpPy = 2‐(pyrid‐4′‐yl)‐4,4,5,5‐tetramethyl‐1, 3‐dioxoimidazoline; H₂TCB = 1, 5‐dicarboxybenzene carboxylic‐2, 4‐diacid) has been synthesized and characterized by X‐ray crystallography analysis. The crystal structure consists of infinite chains of Cu‐(NITpPy)₂(H₂O) units linked by H₂TCB ligands. The complex crystallizes in triclinic system with space group PI. Crystal data: a = 1.0594(2) nm, b = 1.3830(3) nm, c = 1.5551(3) nm, a = 67.75(3)°, β = 89.83(3)°, γ = 70.54(3)°. The variable magnetic susceptibility studies lead to magnetic coupling constant values of J₁= ?11.18 cm‐¹ (Cu—Rad) and J₂ = ?4.06 cm^?1 (Cu—Cu).     

ChemInform Abstract: Structure and Bonding of IrB12‐: Converting a Rigid Boron B12 Platelet to a Wankel Motor.

DFT‐based calculations reveal that the global minimum of IrB₁₂^‐ is a C_3v symmetric bowl‐like structure in which the Ir atom is located on the concave side of the bowl similar to its lighter congeners, CoB₁₂^‐ and RhB₁₂^‐.     

ChemInform Abstract: Scaffolding,Ladders, Chains,and Rare Ferrimagnetism in Intermetallic Borides: Electronic Structure Calculations and Magnetic Ordering.

The electronic structures of “Ti_9‐nFe_2+nRu₁₈B₈” (n = 0, 0.5, 1, 2, 3), including the recently synthesized compounds Ti_9‐nFe_2+nRu₁₈B₈ (n = 1, 2), are determined by TB‐LMTO‐ASA computations.     

Novel Cyanoglucosides from the Leaves of Hydrangea macrophylla

Four non‐cyanogenic cyanoglucosides including hydranitrilosides A₁, A₂, B₁, and B₂ ( 1 – 4 , resp.), together with a new phenolic glucoside, 3‐hydroxy‐4‐methoxybenzoic acid 3‐O‐β‐D ‐glucopyranoside ( 5 ), were isolated from the leaves of Hydrangea macrophylla. Their structures were determined on the basis of chemical and spectral evidence.     

Iron and Cobalt Complexes of a Series of Tridentate P,N, P Ligands — Synthesis,Characterization, and Application in Ethene Polymerization Reactions

A series of tridentate P, N, P ligands comprising a central pyridine unit and two pendent diarylphosphane moieties (2, 6‐bis(CH₂PAr₂)pyridine; Ar = phenyl ( 1 ), 2‐methylphenyl ( 2 ), 2, 4, 6‐trimethylphenyl ( 3 )) as well as the corresponding iron ( 1‐FeCl₂ , 2‐FeCl₂ , 3‐FeCl₂ ) and cobalt ( 1‐CoCl₂ , 2‐CoCl₂ , 3‐CoCl₂ ) complexes were synthesized and characterized. An X‐ray structure analysis of 2‐CoCl₂ and 3‐CoCl₂ exhibited a trigonal‐bipyramidal coordination geometry at the metal center, the two chlorine atoms and the nitrogen occupying the equatorial and the phosphane units the apical positions. IR analysis indicated, that in all complexes the pyridine unit is coordinated to the metal center. The cobalt compounds were applied as catalyst precursors for the polymerization of ethene after activation with MAO.     

Electrochemical and Chemical Syntheses of Trifluoromethylating Reagents and Trifluoromethyl Substituted Compounds

The electroreduction of the halofluoromethanes CF₃Br, CF₂Br₂ and CF₂BrCl has been studied in high‐pressure stainless steel autoclaves at different cathodes [Pt, steel (V2A, V4A), glassy carbon (GC)] and in various solvent‐supporting electrolyte systems (SSE), e.g. DMF/[Bu₄N]Br, NMP/[Bu₄N]BF₄ etc. The reduction potentials for CF₃Br increase from Pt (–1.6 V) < V2A (–1.8 V) < GC (–2.1 V) and are lower for CF₂Br₂ and CF₂BrCl suggesting a reductive cleavage of C‐X bonds as the first step. CF₂Br₂ and CF₂BrCl show a two‐step reduction in accord with the C–X bond energies (C–F > C–Cl > C–Br) and the “Perfluoro‐effect”. The electrolysis of CF₃Br in different SSE‐systems with sacrificial zinc or cadmium anodes has been reinvestigated with our experimental set‐up to elucidate the influence of the experimental conditions on the type and ratio of the products. The observed products CF₃MBr·42L and (CF₃)₂M·42L (M = Zn, Cd; L = DMF or AN) are the same as in the previous investigations, but are obtained in different ratios, as a rule caused by a parallel chemical corrosion of the respective anodes. By using aluminium as sacrificial anode no CF₃Al compounds are formed. The CF₃ species generated by electroreduction of CF₃Br react with the solvents via hydrogen abstraction and formation of CF₃H. The current yield with respect to the dissolution of the Al anode reaches 120 % indicating a considerable chemical corrosion in addition to the anodic oxidation. This result enabled a one‐pot trifluoromethylation reaction of NMP as organic carbonyl substrate and solvent with CF₃Br and aluminium powder (ratio 3 : 2) at higher temperatures (> 70 °C). The complete reaction of CF₃Br to give CF₃H and 1‐methyl‐2‐trifluoromethyl‐4,5‐dihydropyrrol allowed the isolation of the latter by vacuum condensation and distillation in 45 % yield, rel. to the CF₃Br used. Gallium and indium were also applied as sacrificial anodes in combination with CF₃Br as substrate. In both cases, anodic current yields of about 280 % indicated an extreme chemical corrosion together with cathodic metal depositions corresponding to the cathodic current yield. These deposits – in contrast to those of Zn and Cd – do not react with CF₃Br in Grignard‐type conversions to CF₃Ga and CF₃In compounds. So, the observed products (CF₃)_nMBr_3–n·L (M = Ga, In; n 1‐3; L = DMF, NMP) are obviously formed by chemical corrosion of the electro‐activated anodes. Finally, electrochemical and chemical trifluoromethylations were successfully carried out, using R₃SiCl (R = Me, Vi, Ph), Me₃M′Cl (M′ = Ge, Sn) and aluminium anodes or Al‐powder. The products were characterized either after isolation or in the product solutions by NMR‐spectroscopic investigations.     

Synthesis and properties study of novel ferrocenyl isoxazole derivatives

A synthetic procedure based on the 1,3‐dipolar cycloaddition reactions of nitrile oxides and ethynylferrocene derived from ferrocene has been developed to synthesize new ferrocenyl‐isoxazole derivatives. The stable solids were thoroughly characterized by ¹H NMR, FT‐IR, and mass spectroscopy. The structure of (η⁵‐C₅H₅) Fe (η⁵‐C₅H₄) C₃HNOC₆H₄CH₃ was determined by single‐crystal X‐ray diffraction. The electrochemical behaviors of the synthesized ferrocenyl‐isoxazole derivatives were also studied. Copyright © 2005 John Wiley & Sons, Ltd.     

Syntheses and Structures of Coordination Polymers Constructed by Semi‐Rigid Bicarboxylic Acid Ligands

The complexes [Co(L¹)(mpy)] ( 1 ), [Ni(L¹)(mpy)] ( 2 ), [Co(L¹)(tbpy)] · 2H₂O ( 3 ), [Ni₂(L¹)₂(tbpy)₂] · 5H₂O ( 4 ), [Mn₂(L¹)₂(tbpy)₂] · 3H₂O ( 5 ), [Mn(L¹)(biim‐3)] ( 6 ), [Ni₂(L¹)₂(btb)₂(H₂O)] · 2H₂O ( 7 ), [Cu(L²)(mpy)] · 7H₂O ( 8 ), [Co(L²)(tbpy)(H₂O)] ( 9 ), [Ni(L²)(tbpy)(H₂O)] · H₂O ( 10 ), [Cu(L²)(bib)] · 2H₂O ( 11 ), and [Cu(L²)(btb)] · 2H₂O ( 12 ) [H₂L¹ = (3‐carboxyl‐phenyl)‐(4‐(2′‐carboxyl‐phenyl)‐benzyl)ether, H₂L² = 3‐carboxy‐1‐(4′‐carboxybenzyl)‐2‐oxidopyridinium, mpy = 2‐(4‐(4′‐methylphenyl)‐6‐(pyrindin‐2‐yl)pyridin‐2‐yl)pyridine), tbpy = 2‐(4‐(4′‐tert‐butylphenyl)‐6‐(pyrindin‐2‐yl)pyridin‐2‐yl)pyridine), biim‐3 = 1,3‐bis(imidazol‐1′‐yl)propane, btb = 1,4‐bis(1,2,4‐triazol‐1‐ylmethyl)benzene, bib = 1,4‐bis(imidazol‐1′‐ylmethyl)benzene] were synthesized. Compounds 1 – 6 have similar 1D chain structures, which are further linked by π–π interactions to generate supramolecular double chains for 1 and 2 , and supramolecular layers for 3 – 6 . Compound 7 displays a 3D 6‐connected framework with (4⁴ · 6¹¹) topology. Compound 8 features a monomolecular structure, which is further linked by hydrogen bonds between the lattice water molecules and carboxylate oxygen atoms of L² anions to form a 2D supramolecular layer. The monomolecular structures of 9 and 10 are connected by hydrogen bonds and π–π interactions simultaneously to generate supramolecular layers. Compounds 11 and 12 show layer structures.     

Volumetric, Ultrasonic and Transport Properties of Binary Liquid Mixtures Containing Dimethyl Formamide at 303.15 K

Excess volumes （v^E）, ultrasonic velocities （u）, isentropic compressibility （△Ks） and viscosities （η） for the binary mixtures of dimethyl formamide （DMF） with 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,2,4-trichlorobenzene, o-chlorotoluene, m-chlorotoluene, p-chlorotoluene, o-nitrotoluene and m-nitrotoluene at 303.15 K were studied. Excess volume data exhibit an inversion in sign for the mixtures of dimethyl formamide with 1,2- and 1,3-dichlorobenzenes and the property is completely positive over the entire composition range for the mixtures of dimethyl formamide with 1,2,4-trichlorobenzene, o-nitrotoluene and m-nitrotoluene. On the other hand, the quantity is negative for the mixtures of dimethyl formamide with chlorotoluenes. Isentropic compressibility （Ks） has been computed for the same systems from precise sound velocity and density data. Further, deviation of isentropic com- pressibility （△Ks） from ideal behavior was also calculated. AKs values are negative over the entire volume fraction range in all the binary mixtures. The experimental sound velocity data were analysed in terms of Free Length Theory （FLT） and Collision Factor Theory （CFT）. The viscosity data were analysed on the basis of corresponding state approach. The measured data were discussed on the basis of intermolecular interactions between unlike molecules.     

ChemInform Abstract: Unusual Inorganic Biradicals: A Theoretical Analysis.

Quantum chemical calculations at the CASSCF level of theory on the O₃‐homologous molecules CX₂^2‐, NX₂^‐, X₃, OX₂, and FX₂⁺ (X: O, S, Se, Te, Po) indicate that the triatomic inorganic biradicals in the FX₂⁺ series have unusually high biradical character.     

ChemInform Abstract: Charge Modulation in Graphitic Carbon Nitride as a Switchable Approach to High‐Capacity Hydrogen Storage.

Electrical charging of graphitic g‐C₄N₃ and g‐C₃N₄ nanosheets is proposed as a strategy for high‐capacity and electrocatalytically switchable H₂ storage.     

Platinum(II) and Palladium(II) Halides and Pseudohalides with the Ligand Tri(1‐cyclohepta‐2, 4, 6‐trienyl)phosphane. X‐Ray Structural Analysis of [P(C7H7)2(η2‐C7H7)]PtI2

Tri(1‐cyclohepta‐2, 4, 6‐trienyl)phosphane, P(C₇H₇)₃ ( 1 ) ([P] when coordinated to a metal) stabilizes platinum(II) ( 2 ) and palladium(II) dihalides ( 3 ) as [P]MX₂ with X = Cl ( a ), Br ( b ) and I ( c ). The phosphane coordinates to the metal as a chelate ligand via both phosphorus and the central η²‐C=C bond of one of the cyclohepta‐2, 4, 6‐trienyl rings. The complexes were prepared by various routes, mainly by the reaction of (cod)MCl₂ (cod = cycloocta‐1, 5‐diene) with 1 to give the chlorides 2a and 3a , which then could be converted into the bromides 2b , 3b or the iodides 2c , 3c by reaction with NaBr or NaI, respectively. The molecular structure of 2c was determined by X‐ray analysis. Treatment of 2a and 3a with sodium or potassium salts of several pseudohalides afforded the complexes [P]MX₂ 2d (NCO/NCO), 2e₁ (NCS/SCN), 2e₁' (SCN/NCS), 2f₂ (SeCN/SeCN), 3f₁ (NCSe/SeCN), 2g and 3g (X = N₃). Attempts failed to synthesize the cyanides 2h and 3h by the same route. By using an excess of trimethylsilyl cyanide in the reaction with 2a in THF solution, the complex trans‐{[(C₇H₇)₃P]₂Pt(CN)₂} ( 4h ) was obtained instead of 2h . The analogous complexes trans‐{[(C₇H₇)₃P]₂MX₂} with M = Pt ( 4 ) and Pd ( 5 ) for X = Cl ( a ), Br ( b ), I ( c ) could be prepared from the reaction of the corresponding tetrahalogenometallates and 1 (in the case of 5c from PdI₂ and 1 ). In contrast to 4h , the complexes 4a‐c and 5a‐c were found to be labile in solution with respect to partial loss of the phosphane 1 and rearrangement into 2a‐c and 3a‐c , respectively. All compounds were characterized by IR spectroscopy and by multinuclear magnetic resonance spectroscopy (¹H, ¹³C, ³¹P, ⁷⁷Se and ¹⁹⁵Pt NMR). The ligand [P] in 2 and 3 is fluxional with regard to coordination of the C₇H₇ rings to the metal.     

ChemInform Abstract: Starlike Aluminum—Carbon Aromatic Species.

Born‐Oppenheimer molecular dynamics simulations and high‐level quantum chemical computations (B3LYP, MP2, CCSD(T)) reveal the starlike D_5h C₅Al₅^‐ global minimum with five planar tetracoordinate carbon atoms to be a promising candidate for detection by photoelectron detachment spectroscopy.     

ChemInform Abstract: Observation of the Highest Coordination Number in Planar Species: Decacoordinated Ta©B10‐ and Nb©B10‐ Anions.

TaB₁₀^‐ and NbB₁₀^‐ clusters are produced in a laser‐vaporization supersonic molecular beam cluster source and characterized by photoelectron spectroscopy.     

ChemInform Abstract: Crystal Structure and Properties of the Manganese Containing Swedenborgite YBaMn3AlO7.

Small crystals of the title compound are grown from BaAl₂O₄, Y₂BaO₄, and MnO in a floating‐zone mirror‐image furnace.     

Komplexchemie P‐reicher Phosphane und Silylphosphane. XXII. Die Bildung von [η2‐{tBu–P=P–SiMe3}Pt(PR3)2]aus (Me3Si)tBuP–P=P(Me)tBu2 und [η2‐{C2H4}Pt(PR3)2]

Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXII. The Formation of [η²‐{^tBu–P=P–SiMe₃}Pt(PR₃)₂] from (Me₃Si)^tBuP–P=P(Me)^tBu₂ and [η²‐{C₂H₄}Pt(PR₃)₂] (Me₃Si)^tBuP–P = P(Me)^tBu₂ reacts with [η²‐{C₂H₄}Pt(PR₃)₂] yielding [η²‐{^tBu–P=P–SiMe₃}Pt(PR₃)₂]. However, there is no indication for an isomer which would be the analogue to the well known [η²‐{^tBu₂P–P}Pt(PPh₃)₂]. The syntheses and NMR data of [η²‐{^tBu–P=P–SiMe₃}Pt(PPh₃)₂] and [η²‐{^tBu–P=P–SiMe₃}Pt(PMe₃)₂] as well as the results of the single crystal structure determination of [η²‐{^tBu–P=P–SiMe₃}Pt(PPh₃)₂] are reported.     

Palladium(II) and Platinum(II) Complexes with Bisphosphanes, [S2C=C(CN)2]2– and [Se2C=C(CN)2]2– as Chelating Ligands

The palladium(II) and platin(II) 1, 1‐dicyanoethylene‐2, 2‐dithiolates [(L–L)M{S₂C=C(CN)₂}] (M = Pd: L–L = dppm, dppe, dcpe, dpmb; M = Pt: dppe, dcpe, dpmb) were prepared either from[(L–L)MCl₂] and K₂[S₂C=C(CN)₂] or from [(PPh₃)₂M{S₂C=C(CN)₂}] and the bisphosphane. Moreover, [(dppe)Pt{S₂C=C(CN)₂}]was obtained from [(1, 5‐C₈H₁₂)Pt{S₂C=C(CN)₂}] and dppeby ligand exchange. The 1, 1‐dicyanoethylene‐2, 2‐diselenolates[(dppe)M{Se₂C=C(CN)₂}] (M = Pd, Pt) were prepared from[(dppe)MCl₂] and K₂[Se₂C=C(CN)₂]. The oxidation potentials of the square‐planar palladium and platinum complexes were determined by cyclic voltammetry. The reaction of [(dcpe)Pd(S₂C=O)] with TCNE led to a ligand fragment exchange and gave the 1, 1‐dicyanoethylene‐2, 2‐dithiolate [(dcpe)Pd{S₂C=C(CN)₂}] in good yield.     

ChemInform Abstract: At the Border of Intermetallic Compounds and Transition‐Metal Oxides: Crystal Intergrowth of the Zintl Phase Cs4Ge9 and Cs2WO4 or Cs3VO4 as well as Nine‐Atom Cluster Relocation in the Solid State.

Compounds (III) and (VI) containing [Ge₉]^4‐ clusters and oxometallate anions WO₄^2‐ or VO₄^3‐ are characterized by single crystal XRD and Raman spectroscopy.     

ChemInform Abstract: Planarization of B7‐ and B12‐ Clusters by Isoelectronic Substitution: AlB6‐ and AlB11‐.

The structures and chemical bonding of AlB₆^‐ and AlB₁₁^‐ clusters are characterized by PES and DFT calculations.