Bildung siliciumorganischer Verbindungen. 66. (H2Si?CH2)2 und Si-substituierte Derivate

Formation of Organosilicon Compounds. 66. (H₂Si? CH₂)₂ and Si-substituted Derivatives (H₂Si? CH₂)₂ 1 is formed in the reaction of (Cl₂Si? CH₂)₂ with LiAlH₄. In 1 , the halogenation of the SiH bond is so much preferred compared to the ring cleavage reaction, that 1 reacts with Cl₂ or Br₂ to form successively all compounds form 1-monochlor-1,3-disilacyclobutane to (X₂Si? CH₂)₂ (X = Cl, Br). The stability of the 1,3-disilacyclobutane skeleton towards HBr or Br₂ increases as the electronegativity of the Si-substituents increases. Thus, (Cl₂Si? CH₂)₂ is cleaved neither by HBr nor by Br₂, whereas e. g. [H(C₆H₅)Si? CH₂]₂ reacts to [Br(C₆H₅)Si? CH₂]₂ with Br₂, but yields meH(C₆H₅)Si? CH₂? SiBr(C₆H₅)H (me = CH₃) with HBr. In [me(C₆H₅)Si? CH₂]₂, the four-membered ring is cleaved by Br₂ as well as by HBr. The ¹H-, ²⁹Si- and ¹³C-n.m.r. data are reported.     

Über Reaktionen des P4S10 mit siliciumorganischen Verbindungen

Reactions of P₄S₁₀ with Organosilicon Compounds P₄S₁₀ ( 1 ) can be degraded with silicon-nitrogen compounds. 1 reacts with (CH₃)₃Si? N(CH₃)₂ ( 2 a ) and (CH₃)₃Si? N(C₂H₅)₂ ( 2 b ) to yield S?P[N(CH₃)₂]₂SSi(CH₃)₃ ( 3 a ) and ( 3 b ). By the reaction of 1 with [(CH₃)₃Si]₂S ( 4 ) S?P[S? Si(CH₃)₃]₃ ( 6 ) is formed in high yield. (C₆H₅PS₂)₂ ( 7 ) was used as a model to investigate the course of the reaction. This leads to C₆H₅P(S)? [N(CH₃)₂]SSi(CH₃)₃ ( 9 ) and C₆H₅P(S)[SSi(CH₃)₃]₂ ( 10 ). The reaction mechanism will be discussed. The n.m.r. data and mass spectra are reported.     

Spektroskopische Untersuchungen an Siliciumverbindungen. XXXII. Substituenteneinflüsse auf die SiNSi-Bindung in p-substituierten N,N-Bistrimethylsilylanilinen

The influence of the substituents X of the compounds p-X–C₆H₄–N[Si(CH₃)₃]₂ on the positions of the v_s SiNSi vibrational frequencies is described by an empirical equation in dependence on mass and electronic properties of X. The bonding properties of the C? H, Si? C, and Si? N? Si bonds of the disilazane group are discussed by means of complementing informations from ¹³CH coupling constants.     

Über Chalkogenolate. 179. Kupfer(I)-thioxanthate und Thioxanthatocuprate(I)

On Chalcogenolates. 179. Copper(I) Thioxanthates and Thioxanthatocuprates(I) Copper(I) thioxanthates Cu[S₂C? SR], where R = C₂H₅, ⁿC₄H₉, and CH₂? C₆H₅, have been prepared by two procedures and studied by means of diverse methods. They are soluble in ethanolic and acetonic solutions containing the corresponding [S₂C? SR]^? ions in excess to yield thioxanthatocuprates(I) [Cu_n(S₂C? SR)_n+1]^?. The compounds [(C₆H₅)₄P][Cu_n(S₂C? SC₂H₅)_n+1] with n = 1, 4, 6 have been isolated. The existence of [(C₆H₅)₄P][Cu₄(S₂C? SC₄H₉)₅] and [(C₆H₅)₄P][Cu₆(S₂C? SCH₂? C₆H₅)₇] has been ascertained.     

Darstellung und Kristallstrukturen von Dipyridiniomethan-Monohalogenohydro-closo-Dodecaboraten(2−), [(C5H5N)2CH2][B12H11X]; X = Cl,Br, I

Preparation and Crystal Structures of Dipyridiniomethane Monohalogenohydro-closo-Dodecaborates(2?), [(C₅H₅N)₂CH₂][B₁₂H₁₁X]; X = Cl, Br, I [B₁₂H₁₂]^2? reacts with dihalogenomethanes CH₂X₂ in presence of trifluoro acetic acid, yielding the monohalogenododecaborates [B₁₂H₁₁X]^2? (X = Cl, Br, I), which are separated by ion exchange chromatography on diethylaminoethyl(DEAE) cellulose from the starting compound and higher halogenated products. The X-ray structure determinations of [(C₅H₅N)₂CH₂][B₁₂H₁₁Cl] · 2(CH₃)₂SO (orthorhombic, space group Pnma, a = 17.351(6), b = 16.034(5), c = 9.659(2) Å, Z = 4) and of the isotypic bromo and iodo compounds [(C₅H₅N)₂CH₂][B₁₂H₁₁X] (monoclinic, space group P2₁/n, Z = 4; for X = Br: a = 7.339(2), b = 15.275(3), c = 16.761(4) Å, β = 96.80(2)°; for X = I: a = 7.4436(8), b = 15.3510(8), c = 16.9213(16) Å, ß = 97.326(7)°) exhibit crystal lattices build up by columns of substituted boron clusters and angular dications [(C₅H₅N)₂CH₂]²⁺ orientated along the shortest axis which are assembled to alternating layers.     

Synthesis and Characterization of m‐Terphenyl (1,3‐Diphenylbenzene) Compounds Containing Trifluoromethyl Groups

The bis(silyl)triazene compound 2,6‐(Me₃Si)₂‐4‐Me‐1‐(N?N? NC₄H₈)C₆H₂ ( 4 ) was synthesized by double lithiation/silylation of 2,6‐Br₂‐4‐Me‐1‐(N?N? NC₄H₈)C₆H₂ ( 1 ). Furthermore, 2,6‐bis[3,5‐(CF₃)₂‐C₆H₃]‐4‐Me‐C₆H₂‐1‐(N?N? NC₄H₈)C₆H₂ derivative 6 can be easily synthesized by a C,C‐bond formation reaction of 1 with the corresponding aryl‐Grignard reagent, i.e., 3,5‐bis[(trifluoromethyl)phenyl]magnesium bromide. Reactions of compound 4 with KI and 6 with I₂ afforded in good yields novel phenyl derivatives, 2,6‐(Me₃Si)₂‐4‐MeC₆H₂? I and 2,6‐bis[3,5‐(CF₃)₂? C₆H₃]‐4‐MeC₆H₂? I ( 5 and 7 , resp.). On the other hand, the analogous m‐terphenyl 1,3‐diphenylbenzene compound 2,6‐bis[3,5‐(CF₃)₂? C₆H₃]C₆H₃? I ( 8 ) could be obtained in moderate yield from the reaction of (2,6‐dichlorophenyl)lithium and 2 equiv. of aryl‐Grignard reagent, followed by the reaction with I₂. Different attempts to introduce the ^tBu (Me₃C) or neophyl (PhC(Me)₂CH₂) substituents in the central ring were unsuccessful. All the compounds were fully characterized by elemental analysis, melting point, IR and NMR spectroscopy. The structure of compound 6 was corroborated by single‐crystal X‐ray diffraction measurements.     

Wolframkomplexe von Diphosphanylacetylenen

Tungsten Complexes of Diphosphanylacetylenes Diphosphanylacetylenes, R₂P? C?C? PR₂ [R?N(C₂H₅)₂ ( 1 ), N[(CH₂)₂]₂O ( 2 ), OCH₃ ( 3 )] and W(CO)₅ · tetrahydrofurane form the mononuclear complexes R₂P? C?C? PR₂ · W(CO)₅ [R?N(C₂H₅)₂ ( 1a ), N[(CH₂)₂]₂O ( 2a )], the dinuclear complexes (CO)₅W? PR₂? C?C? PR₂? W(CO)₅ [R?N(C₂H₅)₂ ( 1b ), N[(CH₂)₂]₂O ( 2b ), OCH₃ ( 3b )], and the trinuclear complex (CO)₅W? PR₂? C?C? PR₂? W(CO)₄? PR₂? C?C? PR₂? W(CO)₅ [R?N(C₂H₅)₂ ( 4 )]. The new compounds are characterized by their NMR, mass, and IR spectra. The results of an X-ray structural analysis of 4 are reported.     

Metallkomplexe mit biologisch wichtigen Liganden. CLVII [1] Halbsandwich‐Komplexe mit Isocyanoacetylaminosäureestern und Isocyanoacetyldi‐ und tripeptidestern („Isocyano‐Peptide”︁)

Metal Complexes of Biologically Important Ligands, CLVII [1] Halfsandwich Complexes of Isocyanoacetylamino acid esters and of Isocyanoacetyldi‐ and tripeptide esters (?Isocyanopeptides”?) N‐Isocyanoacetyl‐amino acid esters CNCH₂C(O) NHCH(R)CO₂CH₃ (R = CH₃, CH(CH₃)₂, CH₂CH(CH₃)₂, CH₂C₆H₅) and N‐isocyanoacetyl‐di‐ and tripeptide esters CNCH₂C(O)NHCH(R¹)C(O)NHCH(R²)CO₂C₂H₅ and CNCH₂C(O)NHCH(R¹)C(O)NHCH (R²)C(O)NHCH(R³)CO₂CH₃ (R¹ = R² = R³ = CH₂C₆H₅, R² = H, CH₂C₆H₅) are available by condensation of potassium isocyanoacetate with amino acid esters or peptide esters. These isocyanides form with chloro‐bridged complexes [(arene)M(Cl)(μ‐Cl)]₂ (arene = Cp*, p‐cymene, M = Ir, Rh, Ru) in the presence of Ag[BF₄] or Ag[CF₃SO₃] the cationic halfsandwich complexes [(arene)M(isocyanide)₃]⁺X^? (X = BF₄, CF₃SO₃).     

Kristallstruktur von Dipyridiniomethan-Monohalogenohydro-closo-Decaboraten(2–), [(C5H5N)2CH2][2-XB10H9]; X  Cl,Br, I

Crystal Structures of Dipyridiniomethane Monohalogenohydro-closo-Decaborates(2–), [(C₅H₅N)₂CH₂][2-XB₁₀H₉]; X = Cl, Br, I [B₁₀H₁₀]^2? reacts with chlorine, bromine and iodine or with N-halogenosuccinimide, yielding the monohalogenodecaborates [2-XB₁₀H₉]^2? (X = Cl, Br, I), which are separated by ion exchange chromatography on diethylaminoethyl(DEAE) cellulose from the starting compound and higher halogenated products. The X-ray structure determinations of the isotypic chloro and bromo compounds [(C₅H₅N)₂CH₂][2-XB₁₀H₉] (monoclinic, space group C2/c, Z = 8; for X ? Cl: a = 33.174(5), b = 7.2809(4), c = 16.2232(7) Å, β = 113.307(7)°; for X = Br: a = 33.525(11), b = 7.281(2), c = 16.297(4) Å, β = 113.62(2)°) and of the iodo compound [(C₅H₅N)₂CH₂][2-IB₁₀H₉] (monoclinic, space group P2₁, Z = 2, a = 7.143(3), b = 13.568(4), c = 9.479(7) Å, β = 97.57(5)°) show columns of substituted boron clusters [2-XB₁₀H₉]^2?, X = Cl, Br, I and bent dications [(C₅H₅N)₂CH₂]²⁺ along the shortest axis wich are assembled to alternating layers in the crystal lattice.     

Beiträge zur Chemie der Alkylverbindungen von Übergangsmetallen. 55. Darstellung und Eigenschaften von Niobocenium- und Tantalocenium-Salzen – Kristall- und Molekülstruktur von [(C5H5)2NbCl2][BF4] · CH3CN

Contributions to the Chemistry of Organo Transition Metal Compounds. 55. Preparation and Properties of Niobocenium and Tantalocenium Salts — Crystal and Molecular Structure of [(C₅H₅)₂NbCl₂][BF₄] · CH₃CN Niobocenium and tantalocenium compounds of the type [(C₅H₅)₂MCl₂]X (X = BF₄, PBh₄, PF₆) were synthesized from the metallocene dichlorides and ferricenium salts, [(C₅H₅)₂Fe]X, in methylene dichloride or tetrahydrofuran. With acetonitrile as solvent [(C₅H₅)₂MCl₂]X · CH₃CN complexes are formed. Stable methyl compounds of the type [(C₅H₅)₂M(CH₃)₂]X were obtained, when (C₅H₅)₂Ta(CH₃)₂ is oxidized by means of ferricenium salts. The new complexes were characterized by elemental analysis, i. r., and ¹H n.m.r. spectra. The structure of [(C₅H₅)₂NbCl₂][BF₄] · CH₃CN has been determined by X-ray structure analysis. The compound crystallizes in the orthorhombic space group Cmcm with a = 8.324(12), b = 19.581(13), c = 9,563(8) Å and Z = 4. The coordination geometry of the Nb atom is tetrahedrally.     

Metall-Schwefelstickstoff-Verbindungen. 20. Reaktionsprodukte von PdCl2 und Pd(CN)2 mit S7NH. Darstellung und Struktur der Komplexe [Ph6P2N][Pd(S3N)(S5)] und X[Pd(S3N)(CN)2] (X = [Me4N]+, [Ph4P]+)

Metal Sulfur Nitrogen Compounds. 20. Reaction Products of PdCl₂ and Pd(CN)₂ with S₇NH. Preparation and Structure of the Complexes [Ph₆P₂N][Pd(S₃N)(S₅)] and X[Pd(S₃N)(CN)₂] X = [Me₄N]⁺, [Ph₄P]⁺ With PdCl₂ and [Ph₆P₂N]OH S₇NH forms the complex salt [Ph₆P₂N][Pd(S₃N)(S₅)], which could be isolated in two modifications (α- and β-form). The α-form is triclinic, a = 9.347(4), b = 14.410(8), c = 15.440(11) Å, α = 76.27°(5), β = 77.06°(4), γ = 76.61α(4), Z = 2, space group P1 . The β-form is orthorhombic, a = 9.333(2), b = 17.659(4), c = 23.950(6) Å, Z = 4. The structure of the metal complex is the same in the two modifications. One S₃N^? and one S₅^2? are coordinate as chelate ligands to Pd. From S₇NH, Pd(CN)₂, and XOH X = [(CH₃)₄N]⁺ and [(C₆H₅)₄P]⁺ the salts X[Pd(S₃N)(CN)₂] were formed. The (CH₃)₄N-salt is isomorphous with the analogous Ni compound described earlier, the (C₆H₅)₄P-salt is triclinic, a = 9.372(4), b = 10.202(5), c = 13.638(6) Å, α = 86.36α(4), β = 85.66°(4), γ = 88.71°(4), Z = 2, space group P1 . One S₃N^? chelate ligand and two CN^? ions are bound to Pd. In all these complexes the coordination of Pd is nearly square planar.     

Preparation of polymers with substituted allyl end group using dimer of α-methylvinyl monomer as addition fragmentation chain transfer agent at high temperatures

The dimerization of methyl methacrylate, ethyl methacrylate, methacrylonitrile, and α-methylstyrene to 2-substituted-1-allylic compounds [CH₂?C(X)CH₂C(CH₃)₂X] (X = COOR, C₆H₅, or CN), and methyl α-ethylacrylate to a 3-substituted-2-allylic compound [CH₃CH?C(COOCH₃)CH₂C(CH₃)(C₂H₅) COOCH₃] was carried out by catalytic chain transfer using benzylbis (dimethylglyoximato) (pyridine) cobalt (III). These dimers were then used as addition-fragmentation chain transfer agents in the polymerizations of methyl methacrylate and styrene at 80⁰C or above. Cross-dimers from methacrylic ester-α-methylstyrene and methacrylonitrile-α-methylstyrene mixtures were similarly prepared. Except for those from methyl α-ethylacrylate and methacrylonitrile, all the dimers participated in the addition-fragmentation and the copolymerization to different extents. The dimer of methyl α-ethylacrylate was actually inactive during the styrene and methyl methacrylate polymerizations. The methacrylonitrile dimer was primarily incorporated in the polymer chain through copolymerization. Among the dimer and the cross-dimers from α-methylstyrene with the other monomers, those bearing the α-methylstyrene moiety in the α-substituent [CH₂?C(X)CH₂C(CH₃)₂C₆H₅, X?COOCH₃, COOC₂H₅, and CN] are noted as highly reactive chain transfer agents. © 1994 John Wiley & Sons, Inc.     

螺桨烷型分子BX[(CH_2)_n]_3和BX(CH_2)[CH(CH_2)_nCH](X=N,P)的结构和性质

采用密度泛函理论(DFT)研究了螺桨烷型分子BX[(CH2)n]3和BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的结构、稳定性、化学键和电子光谱性质.计算结果表明这些分子都是稳定的.BX[(CH2)n]3(X=N,P;n=1-6)的最高占据分子轨道(HOMO)和最低空分子轨道(LUMO)之间的能隙均大于5.20 eV,其中BN[CH2]3和BP[CH2]3的能隙超过7.0 eV,与C5H6的能隙(7.27 eV)很接近,BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的能隙在6.80 eV左右.所研究分子能量的二阶差分表明BN[(CH2)3]3、BP[(CH2)4]3及BX(CH2)[CH(CH2)2CH](X=N,P)是最稳定的.BX[(CH2)n]3的Wiberg键级表明除了BN[(CH2)n]3(n=2和6)中不存在B―N键,其它化合物中B和N均形成了化学键,BP[(CH2)n]3中除了BP[(CH2)2]3不存在B―P键,其它的均存在.电子密度的拓扑分析表明N―B键属于离子键,而P―B键具有共价键特征.BX[(CH2)n]3(X=N,P)的第一垂直激发能分别在191.1-284.8 nm和191.8-270.1 nm之间,BX(CH2)[CH(CH2)n CH](X=N,P)的第一垂直激发能分别在190.5-199.7 nm和209.0-221.3 nm之间.     

Umlagerungen und Spaltungsreaktionen von Silylphosphinen

SiH- and SiCl-containing Silylphosphines rearrange acc. to equ. (1), (2). Equations (1) and (2) are not reversible, because there are cleavages acc. to equ. (3). (4). Also HSiCl₃ cleaves H₃Si? P(C₂H₅)₂ acc. to equ. (5). Si-methyl-free, SiH-containing Silylphosphines disproportionateal ready at room temperature within a few months acc. to equ. (6), (7). H₂Si[P(C₂H₅)₂]₂ however, is stable under the same conditions. Si? CH₃ containing silylphosphines such as CH₃SiH₂? P(C₂H₅)₂, CH₃Si[P(C₂H₅)₂]₃ and similar ones are stable compounds which can be destilled. To prepare pure HSi[P(C₂H₅)₂]₃, the side-reactions ace. to equ. (I) are avoided by reduction of the Sic1 groups with LiH. Reduction with LiAlH₄ leads to a cleavage of the Si? P bond.     

Replacement of Trimethylamine in Trimethylamine‐trispentafluoroethyl‐borane. Structures of [(C2F5)3BNMe3], [NMe4][(C2F5)3BOH], and K[(C2F5)3BCH2(CO)C6H5]

Trimethylamine‐tris(pentafluoroethyl)borane [(C₂F₅)₃BNMe₃] ( 1 ) reacts at 190 °C with water under displacement of the trimethylamine ligand to yield the hydroxy‐tris(pentafluoroethyl)borate [(C₂F₅)₃BOH]^? ( 2 ). In tributylamine 1 reacts with alkynes HC≡CR to form novel ethynyl‐tris(pentafluoroethyl)borate anions [(C₂F₅)₃BC≡CR]^? – R = C₆H₅ ( 3 ), C₆H₄CH₃ ( 4 ), Si(CH(CH₃)₂)₃ ( 5 ) – in moderate yields. Compound 3 adds water across the triple bond to form the novel anion [(C₂F₅)₃BCH₂(CO)C₆H₅]^? ( 6 ). The structures of [(C₂F₅)₃BNMe₃], [NMe₄][(C₂F₅)₃BOH] and K[(C₂F₅)₃BCH₂(CO)C₆H₅] have been determined by x‐ray crystallography.     

Influence of Cyclopentadienyl Ring‐Tilt on Electron‐Transfer Reactions: Redox‐Induced Reactivity of Strained [2] and [3]Ruthenocenophanes

In contrast to ruthenocene [Ru(η⁵‐C₅H₅)₂] and dimethylruthenocene [Ru(η⁵‐C₅H₄Me)₂] ( 7 ), chemical oxidation of highly strained, ring‐tilted [2]ruthenocenophane [Ru(η⁵‐C₅H₄)₂(CH₂)₂] ( 5 ) and slightly strained [3]ruthenocenophane [Ru(η⁵‐C₅H₄)₂(CH₂)₃] ( 6 ) with cationic oxidants containing the non‐coordinating [B(C₆F₅)₄]^? anion was found to afford stable and isolable metal?metal bonded dicationic dimer salts [Ru(η⁵‐C₅H₄)₂(CH₂)₂]₂[B(C₆F₅)₄]₂ ( 8 ) and [Ru(η⁵‐C₅H₄)₂(CH₂)₃]₂[B(C₆F₅)₄]₂ ( 17 ), respectively. Cyclic voltammetry and DFT studies indicated that the oxidation potential, propensity for dimerization, and strength of the resulting Ru?Ru bond is strongly dependent on the degree of tilt present in 5 and 6 and thereby degree of exposure of the Ru center. Cleavage of the Ru?Ru bond in 8 was achieved through reaction with the radical source [(CH₃)₂NC(S)S?SC(S)N(CH₃)₂] (thiram), affording unusual dimer [(CH₃)₂NCS₂Ru(η⁵‐C₅H₄)(η³‐C₅H₄)C₂H₄]₂[B(C₆F₅)₄]₂ ( 9 ) through a haptotropic η⁵–η³ ring‐slippage followed by an apparent [2+2] cyclodimerization of the cyclopentadienyl ligand. Analogs of possible intermediates in the reaction pathway [C₆H₅ERu(η⁵‐C₅H₄)₂C₂H₄][B(C₆F₅)₄] [E=S ( 15 ) or Se ( 16 )] were synthesized through reaction of 8 with C₆H₅E?EC₆H₅ (E=S or Se).     

Umsetzungen von Borazinderivaten mit Bis(trimethylsilyl)-acetamid und Lithiumhexamethyldisilazan

Bis-(trimethylsilyl)acetamide (BSA) reacts with borazines [RNBX]₃, R=H,X=F; R=CH₃,X=F; R=C₆H₅,X=F and R=C₆H₅,X=Cl to the corresponding borazines,X=OSi(CH₃)₃. The¹H-NMR signal of the Si(CH)₃-groups of [C₆H₅NBOSi(CH₃)₃]₃ is at abnormally high field. With [CH₃NBCl]₃,BSA forms borazines which contain both Si(CH₃)₃O- and O?C(CH₃)=NSiR₃ groups bonded to the boron atoms. With LiN[Si(CH₃)₃]₂, [CH₃NBCl]₃ forms silylaminoboranes.¹H-NMR, mass spectrometric and analytical data are reported.     

Aminomethylierung von Thiophosphorsäuredialkylester-, Phosphon- bzw. Thiophosphonsäurealkylesteramiden,Phosphon- bzw. Thiophosphonsäurediamiden und Diphenylthiophosphinsäureamid

Aminomethylation of Phosphoro-, Phosphono-, Phosphinoamidoates and -amidothioates Dialkylphosphoroamidates, alkyl-phosphonoamidates and phosphonoamidothioates react with C₂H₅O? CH₂? NR₂ and HCOH/HNR₂, respectively, as like as a N-aminomethylation forming the corresponding derivatives of the general formula R₂P(X)? NR′? CH₂? NR″₂? R = alkoxy, alkyl, aryl; R′ = H, alkyl; X = O, S; R″ = alkyl, cycloalkyl —. Under the same conditions phosphonodiamidoates and phosphonodiamidothioates yield RP(X)-[NR′? CH₂? NR″₂]₂ or RP(X)? NHR′? (NR′? CH₂? NR″₂) only. These compounds are not formed by interactions of RP(X)(NR′? CH₂OH)₂ with sec. amines. The aminomethylation of (C₆H₅)₂P(S)NH₂ gives unexceptional [(C₆H₅)₂P(S)]₂N? CH₂? NR′₂. The i.r. and ¹H-n.m.r. data of the prepared compounds, which can't be distilled mostly, are discussed.     

Synthesis and single crystal X‐ray determination of the Schiff base 1‐[(2‐isopropyl‐5‐methylphenoxy)hydrazono] ethyl ferrocene

The reaction of acetylferrocene [Fe(η‐C₅H₅)(η‐C₅H₄COCH₃)] (1) with (2‐isopropyl‐5‐methylphenoxy) acetic acid hydrazide [CH₃C₆H₃CH(CH₃)₂OCH₂CONHNH₂] (2) in refluxing ethanol gives the stable light‐orange–brown Schiff base 1‐[(2‐isopropyl‐5‐methylphenoxy)hydrazono] ethyl ferrocene, [CH₃C₆H₃CH(CH₃)₂OCH₂CONHN?C(CH₃)Fe(η‐C₅H₅)(η‐C₅H₄)] (3). Complex 3 has been characterized by elemental analysis, IR, ¹H NMR and single crystal X‐ray diffraction study. It crystallizes in the monoclinic space group P2₁/n, with a = 9.6965(15), b = 7.4991(12), c = 29.698(7) Å, β = 99.010(13) °, V = 2132.8(7) ų, D_calc = 1.346 Mg m^?3; absorption coefficient, 0.729 mm^?1. The crystal structure clearly shows the characteristic [N? H···O] hydrogen bonding between the two adjacent molecules of 3. This acts as a bidentale ligand, which, on treatment with [Ru(CO)₂Cl₂] _n, gives a stable bimetallic yellow–orange complex (4). Copyright © 2002 John Wiley & Sons, Ltd.     

Structure and formation of gaseous [C4H6O]+˙ ions: 1—The enolic ions [CH2C(OH)?CHCH2]+˙ and [CH2CH?CHCH(OH)]+˙ and their relationship with their keto counterparts

The [C₄H₆O]^+˙ ion of structure [CH₂?CHCH?CHOH]^+˙ (a) is generated by loss of C₄H₈ from ionized 6,6-dimethyl-2-cyclohexen-1-ol. The heat of formation ΔH_f of [CH₂?CHCH?CHOH]^+˙ was estimated to be 736 kJ mol^?1. The isomeric ion [CH₂?C(OH)CH?CH₂]^+˙ (b) was shown to have ΔH_f, ? 761 kJ mol^?1, 54 kJ mol^?1 less than that of its keto analogue [CH₃COCH?CH₂]^+˙. Ion [CH₂?C(OH)CH?CH₂]^+˙ may be generated by loss of C₂H₄ from ionized hex-1-en-3-one or by loss of C₄H₈ from ionized 4,4-dimethyl-2-cyclohexen-1-ol. The [C₄H₆O]^+˙ ion generated by loss of C₂H₄ from ionized 2-cyclohexen-1-ol was shown to consist of a mixture of the above enol ions by comparing the metastable ion and collisional activation mass spectra of [CH₂?CHCH?CHOH]^+˙ and [CH₂?C(OH)CH?CH₂]^+˙ ions with that of the above daughter ion. It is further concluded that prior to their major fragmentations by loss of CH₃˙ and CO, [CH₂?CHCH?CHOH]⁺˙ and [CH₂?C(OH)CH?CH₂]^+˙ do not rearrange to their keto counterparts. The metastable ion and collisional activation characteristics of the isomeric allenic [C₄H₆O]^+˙ ion [CH₂?C?CHCH₂OH]^+˙ are also reported.