Wasserstoffbrückenbindungen in zweikernigen μ-Hydroxobis[trichloroantimon(V)]-Komplexen mit Phosphatbzw. Phosphonatgruppen als überbrückende Liganden

Hydrogen Bonds in Binuclear μ-Hydroxo-bis[trichloroantimony(V)] Complexes with Phosphate or Phosphonate Groups as Bridging Ligands Benzylphosphonic acid monoalkylesters react with antimony(V) chloride and water to yield Cl₃SbO(OH)[(C₆H₅CH₂)RPO₂]SbCl₃ · H₂O ( 1 : R = OCH₃; 2 : R = OC₂H₅). With difluoro phosphoric acid only Cl₃SbO(OH)(F₂PO₂)SbCl₃ ( 3 ) can be isolated. The crystal and molecular structures of 1 to 3 were determined. 1 and 2 both crystallizing orthorhombic in the space group Pnma are hydroxonium salts H₃O⁺[Cl₃SbO₂((C₆H₅CH₂)RPO₂)SbCl₃]^–. Strong hydrogen bridges link cations and anions to chains. One of the hydrogen atoms of the cation makes a weak but important OH/π interaction to the para C atom of the benzyl group. In 3 (monoclinic, P2₁/n) the molecules are connected by hydrogen bridges to fourfold δ and helices λ. In solution there is a rapid intermolecular exchange of protons. IR and NMR data are communicated and briefly discussed.     

Zweikernige Antimon(V)-Komplexe mit Diphenylphosphato-Brückenliganden

Binuclear Antimony(V) Complexes with Bridging Diphenylphosphato Ligands The binuclear antimony(V) complexes Cl₃Sb(O)[(C₆H₅O)₂PO₂]₂SbCl₃ ( 1 ), Cl₃Sb(O)[(C₆H₅O)₂PO₂](OCH₃)SbCl₃ ( 2 ), Cl₃Sb(O)[(C₆H₅O)₂PO₂](OH)SbCl₃ ( 3 ) and Cl₄Sb[(C₆H₅O)₂PO₂]₂SbCl₄ ( 4 ) are prepared by reaction of diphenylphosphoric acid with antimony(V) chloride, water and methanol in different molar ratios. The progress of the reactions was controlled by the ³¹P-NMR signals. 1 crystallizes triclinic in the space group P1 with a = 918.8, b = 1312.9, c = 1395.8 pm, α = 91.91, β = 101.36, γ = 95.90° and Z = 2. 2 to 4 crystallize in monoclinic space groups: 2 : C2/c, a = 2753.4, b = 1156.1, c = 1476.7 pm, β = 98.01° and Z = 8; 3 : P2₁/c, a = 1234.8, b = 1471.8, c = 1263.4 pm, β = 107.15° and Z = 4; 4 : P2₁/n, a = 1943.8, b = 940.8, c = 2015.6 pm, β = 109.87° and Z = 4 resp. The NMR spectra are discussed and some IR data are communicated.     

Untersuchungen über das Reaktionsverhalten von Antimonpentachlorid. III [1]. Zur Reaktion von Antimon (V)-chlorid mit Methylisocyanat

Studies on the Reactivity of Antimony Pentachloride. III. The Reaction of Antimony(V) Chloride and Methylisocyanate Methylisocyanate CH₃NCO reacts with SbCl₅ in boiling CCl₄ by an insertion-reaction to a product of the formula C₅H₆Cl₉N₂O₂Sb I, which has the chlorformamidinium-structure (Cl? C(O)? N(CH₃)? CCl? N(CH₃)? C(O)? Cl)⊕SbCl₆?. Hydrolysis of I yields the heterocycle C₅H₆N₂O₄ II. The reaction with methanol gives (CH₃? NH? CCl? NH? CH₃)⊕SbCl₆? III and (CH₃? NH? CCl? N(CH₃)? C(O)? OCH₃)⊕SbCl₆? IV. The i.r. and Raman spectra of the compounds I, III and IV are discussed.     

d,h-m̈-Alkoxoalkylphosphonato-e-m̈-alkoxo-f-m̈-oxo-bis[trichloroantimon(V)]-Verbindungen

d,h-m?-Alkoxoalkylphosphonato-e-m?-alkoxo-f-m?-oxo-bis[trichloroantimony(V)] Compounds The binuclear antimony(V) complexes Cl₃Sb(O)[R³(R¹O)PO₂](OR²)SbCl₃ 1 to 7 with R¹, R² and R³ = Me or Et in solution slowly exchanges the R² groups between the equatorial oxygen atoms of the Sb₂O₂ ring. The SbO(3)PO(3)Sb ringsystem makes rapid pseudorotation. The resulting isomeres are detected by nmr spectroscopy.     

Dihydroxytrimethylstiboran – einige Eigenschaften und Struktur

Dihydroxytrimethylstiborane – Properties and Structure (CH₃)₃Sb(OH)₂ · H₂O ( 1 ) is prepared by reaction of (CH₃)₃SbCl₂ and NaOH. 1 reacts with CO₂ to yield [(CH₃)₃SbOH]₂CO₃ · 2 H₂O ( 2 ). Thermogravimetric investigations and mass spectra show that 1 and 2 decompose at low temperature and low pressure to H₂O, CO₂ and (CH₃)₃SbO. The crystal and molecular structures of 1 and 2 are determined. 1 crystallizes orthorhombic (Pbca) with a = 1185.2, b = 1069.6, c = 1207.6 pm and Z = 8. 2 crystallizes in the acentric monoclinic space group Cc with a = 657.3, b = 1168.5, c = 2048.2 pm, β = 95,33° and Z = 4. The infrared spectra are discussed with regard to the hydrogen bonding.     

Addukte aus Phosphorylverbindungen und SbCl5 Darstellung und IR-Spektren der 1:1-Addukte aus Chlordimethylamino- bzw. Chlordimethylamino-methoxi-phosphorylverbindungen und Antimon(V)-chlorid

Adducts of Phosphoryl Compounds and SbCl₅ Preparation and IR Spectra of 1:1 Addition Compounds from Chlorodimethylamino- resp. Chlorodimethylaminomethoxiphosphoryl Compounds and Antimony(V) Chloride The addition compounds (CH₃O)₂[(CH₃)₂N]PO · SbCl₅ ( II ), (CH₃O)[(CH₃)₂N]₂PO · SbCl₅ ( III ), [(CH₃)₂N]₃PO · SbCl₅ ( IV ), Cl₂[(CH₃)₂N]PO · SbCl₅ ( VI ), Cl[(CH₃)₂N]₂PO · SbCl₅ ( VII ), and Cl(CH₃O)[(CH₃)₂N]PO · SbCl₅ ( VIII ) are prepared by reaction of the phosphoryl compounds with antimony(V) chloride. The influence of the Lewis acid to the bonds of the phosphoryl compounds is discussed. The ³¹P-n.m.r. data of the adducts are communicated and compared with those of the free phosphoryl compounds.     

Komplexchemie polyfunktioneller Liganden. XXX. Komplexe des Tetrakis(diphenyl-dichlor-phosphoranomethyl)-methan mit FeCl3, SnCl4 und SbCl5

Complex Chemistry of Polyfunctional Ligands. XXX. Complexes of the Tetrakis(diphenyl-dichloro-phosphoranmethyl)methane with FeCl₃, SnCl₄, and SbCl₅ The reaction of C[CH₂P(C₆H₅)₂Cl₂]₄ and FeCl₃ in the 1:4 stoichiometric quantities results in the formation of the tetraphosphonium salt A and the in 1:2 ratio the spirocyclic compound B has been formed. Coincident with the synthesis of B CH₃CN has been chlorinated to some extend. Surprisingly C[CH₂P(C₆H)₂Cl₂]₄ and SnCl₄ yields the much largely non ionic 1:2 adduct C[CH₂P(C₆H₅)₂Cl₂]₄ · 2 SnCL₄, whereas SbCl₅ reacts to the expected salt C[CH₂P(C₆H₅)₂Cl SbCl₆]₄.     

dh-μ-Carboxilato-e-μ-hydroxo-f-μ-oxo-bis[trichloroantimone(V)] Struktur und spektroskopsiche Untersuchungen

dh-μ-Carboxilato-e-μ-hydroxo-f-μ-oxo-bis[trichloroantimonies(V)] Structure and Spectroscopic Investigations The title compounds can be prepared by reaction of SbCl₅ · H₂O and RCOOH (R ? CF₃, CCl₃, CHCl₂, CH₂Cl, CH₃, CH₃CH₂, (CH₃)₂CH, H) or by reaction of H₅O₂⁺SbCl₆^? and RCO₂SbCl₄ in good yields. ¹H-NMR investigations proove that there is a rapid exchange between the components in the reaction mixture. The vibrational spectra are discussed in view of the CO₂ vibrations and hydrogen bonding. The crystal and molecular structure of dh-μ-Trichloroacetato-e-μ-hydroxo-f-μ-oxo-bis[trichloroantimony(V)] is determined by X-ray analysis.     

Übergangsmetall-carben-Komplexe. LXXX. α-Alkoxy- und α,α-dialkoxysubstituierte Phenylacetyl-(pentacarbonyl)metallate und Pentacarbonyl[alkoxy(benzyl)-carben]-Komplexe des Chroms und Wolframs

Vibrational Spectra of Dichlorophosphorylmethylamine CH₃? NH? P(?O)Cl₂ and its Adducts with SbCl₅ and SnCl₄ The vibrational spectra of liquid samples and solutions, as well as cryoscopic molecular weight determinations show that CH₃? NH? P(?O)Cl₂ exists largely in the dimeric form. The association occurs through hydrogen bridges. The adducts SbCl₅ · CH₃? NH? P(?O)Cl₂ and SnCl₄ · 2 CH₃? NH? P(?O)Cl₂ are formed through addition via an oxygen atom. The ligands have cis-configuration in the tin compound.     

d,h-μ-Benzylalkoxophosphonato-e-μ-alkoxo-f-μ-oxo-bis[trichloroantimon(V)]-Verbindungen

d, h-μ-Benzylalkoxophosphonato-e-μ-alkoxo-f-μ-oxo-bis[trichloroantimony(V)] Compounds The binuclear antimony(V) complexes Cl₃Sb(O)[R³(R¹O)PO₂](OR²)SbCl₃ 1 – 6 with R¹ = R² = CH₃, C₂H₅ and R³ = C₆H₅CH₂, (CH₃)₃C₆H₂CH₂ in solution slowly exchanges the R² groups between the oxygen atoms of the Sb₂O₂ ring. The SbOPOSb ringsystem makes rapid pseudorotation. The isomeres are detected by nmr spectroscopy. 1 (R¹ = R² = CH₃) crystallizes in the orthorhombic space group Pnma with a = 1247.0, b = 1324.1, c = 1207.9 pm and Z = 4. 2 (R¹ = CH₃, R² = C₂H₅) and 5 (R¹ = R² = CH₃, R³ = (CH₃)₃ · C₆H₂CH₂) crystallizes triclinic in the space group P-1 with a = 984.1, b = 1026.7, c = 1079.9 pm, α = 87.93, β = 75.70, γ = 87.62° and Z = 2 and a = 1164.6, b = 1296.9, c = 1712.9 pm, α = 109.9, β = 96.3, γ = 100.2° and Z = 4 resp., with two crystallographically independent molecules in the asymmetric unit.     

Isomorphous rare‐earth tris[bis(2,6‐diisopropylphenyl) phosphate] complexes and their catalytic properties in 1,3‐diene polymerization and in the inhibited oxidation of polydimethylsiloxane

Crystals of mononuclear tris[bis(2,6‐diisopropylphenyl) phosphato‐κO]pentakis(methanol‐κO)lanthanide methanol monosolvates of lanthanum, [La(C₂₄H₃₄O₄P)₃(CH₃OH)₅]·CH₃OH, ( 1 ), cerium, [Ce(C₂₄H₃₄O₄P)₃(CH₃OH)₅]·CH₃OH, ( 2 ), and neodymium, [Nd(C₂₄H₃₄O₄P)₃(CH₃OH)₅]·CH₃OH, ( 3 ), have been obtained by reactions between LnCl₃(H₂O)_n (n = 6 or 7) and lithium bis(2,6‐diisopropylphenyl) phosphate in a 1:3 molar ratio in methanol media. Compounds ( 1 )–( 3 ) crystallize in the monoclinic P2₁/c space group and have isomorphous crystal structures. All three bis(2,6‐diisopropylphenyl) phosphate ligands display a κO‐monodentate coordination mode. The coordination number of the metal atom is 8. Each [Ln{O₂P(O‐2,6‐ⁱPr₂C₆H₃)₂}₃(CH₃OH)₅] molecular unit exhibits four intramolecular O—H…O hydrogen bonds, forming six‐membered rings. The unit forms two intermolecular O—H…O hydrogen bonds with one noncoordinating methanol molecule. All six hydroxy H atoms are involved in hydrogen bonding within the [Ln{O₂P(O‐2,6‐ⁱPr₂C₆H₃)₂}₃(CH₃OH)₅]·CH₃OH unit. This, along with the high steric hindrance induced by the three bulky diaryl phosphate ligands, prevents the formation of a hydrogen‐bond network. Complexes ( 1 )–( 3 ) exhibit disorder of two of the isopropyl groups of the phosphate ligands. The cerium compound ( 2 ) demonstrates an essential catalytic inhibition in the thermal decomposition of polydimethylsiloxane in air at 573 K. Catalytic systems based on the neodymium complex tris[bis(2,6‐diisopropylphenyl) phosphato‐κO]neodymium, ( 3′ ), which was obtained as a dry powder of ( 3 ) upon removal of methanol, display a high catalytic activity in isoprene and butadiene polymerization.     

Triorganoantimon- und Triorganobismutdisulfonate Kristall- und Molekülstrukturen von (C6H5)3M(O3SC6H5)2 (M = Sb,Bi)

Triorganoantimony and Triorganobismuth Disulfonates. Crystal and Molecular Structure of (C₆H₅)₃M(O₃SC₆H₅)₂(M = Sb, Bi) Triorganoantimony disulfonates R₃Sb(O₃SR′)₂ [R = CH₃ = Me, C₆H₅ = Ph; R′ = Me, CH₂CH₂OH, Ph, 4-CH₃C₆H₄. R = Ph; R′ = 2,4-(NO₂)₂C₆H₃], Me₃Sb(O₃SCF₃)₂ · 2 H₂O and triphenylbismuth disulfonates Ph₃Bi(O₃SR′)₂ [R = Me, CF₃, CH₂CH₂OH, Ph, 4-CH₃C₆H₄, 2,4-(NO₂)₂C₆H₃] have been prepared by reaction of Me₃Sb(OH)₂, (Ph₃SbO)₂, and Ph₃BiCO₃, respectively, with the appropriate sulfonic acids. From vibrational data an ionic structure is inferred for Me₃Sb(O₃SCF₃)₂ · 2 H₂O and Me₃Sb(O₃SCH₂CH₂OH)₂, and a covalent structure for the other compounds with a penta-coordinated central atom with trigonal bipyramidal surrounding (Ph or Me in equatorial, unidentate sulfonate ligands in apical positions). Ph₃M(O₃SPh)₂ (M = Sb, Bi) crystallize monoclinic [space group P2₁/c; M = Sb/Bi: a = 1 611.5(8)/1 557.4(9), b = 987.5(6)/1 072,5(8), c = 1 859.9(9)/1 696.5(9) pm, β = 105.71(5)/96.62(5)°; Z = 4; d(calc.) 1.556/1.781 Mg · m^?3; V_cell = 2 849.2 · 10⁶/2 814.8 · 10⁶ pm³; structure determination from 3 438/3 078 independent reflexions (I ≥ 3σ(I)), R(unweighted) = 0.030/0.029]. M is bonding to three Ph groups in the equational plane [mean distances Sb/Bi? C:210.1(4)/219.1(7) pm] and two sulfonate ligands with O in apical positions [distances Sb? O: 210.6(3), 212.8(2); Bi? O: 227.6(5), 228.0(4) pm]. Weak interaction of M with a second O atom of one sulfonate ligand is inferred from a rather short M? O contact distance [Sb? O: 327.4(4), Bi? O: 312.9(5) pm], and from the distortion of equatorial angles [C? Sb? C: 128.4(2), 119.2(2), 112.2(2); C? Bi? C: 135.9(3), 117.8(3), 106.3(3)°]     

Molybdänhalogenidcluster mit sechs terminalen Alkoholatliganden: (C18H36N2O6Na)2[Mo6Cl8(OCH3)6] · 6CH3OH und (C18H36N2O6Na2)2[Mo6Cl8(OC6H5)6]

Molybdenum(II) Halide Clusters with six Alcoholate Ligands: (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₈(OCH₃)₆] · 6CH₃OH and (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₈(OC₆H₅)₆] . The reaction of Na₂[Mo₆Cl₈(OCH₃)₆] and 2,2,2-crypt yields (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₈(OCH₃)₆] · 6 CH₃OH ( 1 ), which is converted to (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₈(OC₆H₅)₆] ( 2 ) by metathesis with phenol. According to single crystal structure determinations ( 1 : P3 1c, a=14.613(3) Å, c=21.036(8) Å; 2 : P3 1c, a=15.624(1) Å, c=19.671(2) Å) the compounds contain anionic clusters [Mo₆Cl₈ⁱ(OR^a)₆]^2? ( 1 : d(Mo—Mo) 2.608(1) Å to 2.611(1) Å, d(Mo—Cl) 2.489(1) Å to 2.503(1) Å, d(Mo—O) 2.046(4) Å; 2 : d(Mo—Mo) 2.602(3) Å to 2.608(3) Å, d(Mo—Cl) 2.471(5) Å to 2.4992(5) Å, d(Mo—O) 2.091(14) Å). Electronic interactions of the halide cluster and the phenolate ligands in [Mo₆Cl₈(OC₆H₅)₆]^2? is investigated by means of UV/VIS spectroscopy and EHMO calculations.     

Chloroantimon(V)-phosphate

Chloroantimony(V) Phosphates The 1:1 adducts of alkoxiphosphoryl compounds and antimony(V) chloride eliminate alkylchloride to yield the dimere tetrachloroantimony(V) phosphates [Cl₄SbO₂PCl₂]₂ I, [Cl₄SbO₂P(OCH₃)Cl]₂ II, [Cl₄SbO₂P(OCH₃)₂]₂ III, [Cl₄SbO₂P(OC₂H₅)Cl]₂ IV, [Cl₄SbO₂P(OC₂H₅)₂]₂ V and the tetramere trichloroantimony(V) phosphates [Cl₃SbO₃POCH₃]₄ VI resp. [Cl₃SbO₃POC₂H₅]₄ VII. III can also be prepared by reaction of K⁺O₂P(OCH₃)₂^? with SbCl₅. The vibrational spectra, the ¹H- and the ³¹P-n.m.r. data of II, IV, V, VI and VII are communicated.     

Reaktionsprodukte aus Chlormethoxiphosphinen und Antimon(V)-chlorid. Schwingungsspektren der 1:1 Addukte aus Methoxiphosphorylverbindungen und Antimon(V)-chlorid

Reaction Products of Chloromethoxiphosphines and Antimony (V) Chloride. Vibrational Spectra of the 1:1-adducts of Methoxiphosphoryl Compounds and Antimony (V) Chloride Chloromethoxiphosphines react with antimony(V) chloride in a redox process to yield the chloromethoxiphospllonium hexachloroantimonates(V) (CH₃O)₃PCl₂⁺SbCl₆^? (II) and CH₃OPCl₃⁺SbCl₆^? (III). II, III, (CH₃O)₃PCl⁺SbCl₆^?(1) and (CH₃O)₄P⁺SbCl₆^? eliminate easily methyl chloride and give the addition compounds OP(OCH₃)₃·SbCl₅(IV), OPCl(OCH₃)₂ · SbCl₅ (V), OPCl₂(OCH₃)·SbCl₅ (VI) and OPCl₃·SbCl₅ (VII). The vibrational spectra of IV, V nnd VI are discussed.     

α,ω-Disubstituted polymethylpolyphosphonates and polyphenylpolyphosphonates from condensation polymerization

Condensation polymerization of phosphonates through formation of P? O? P linkages has been achieved by (1) volatilization of methyl chloride from mixtures of CH₃P(O)Cl₂ with CH₃P(O)(OCH₃)₂; (2) volatilization or chemical removal of water from CH₃P(O)(OH)₂; and (3) volatilization of HCl from mixtures of CH₃P(O)Cl₂ with CH₃P(O)(OH)₂ or C₆H₅P(O)Cl₂ with C₆H₅P(O)(OH)₂. Depending on the proportions of the reagents, the polymerization products consist of various mixtures of chain molecules of the type \documentclass{article}\pagestyle{empty}\begin{document}${\rm X \hbox{--} P}({\rm O})({\rm R})\rlap{--}[{\rm O \hbox{--} P}({\rm O})({\rm R})\rlap{--}]_n {\rm X}$\end{document} for R = CH₃ and X = OCH₃, Cl, or OH, or for R = C₆H₅, x = Cl or OH. ³¹P nuclear magnetic resonance (NMR) was used to investigate both the polymethylpolyphosphonates and the polyphenylpolyphosphonates; and ¹H NMR of the CH₃P and CH₃O moieties was also used to study the polymethylpolyphosphonates. In the methoxyl-terminated polymethylpolyphosphonates, which was the system studied most extensively, no detectable amounts of cyclic molecules were found at equilibrium, but a crystalline methylphosphonic anhydride, CH₃PO₂, exhibited some ring structures. The equilibrium size distributions gave evidence that the sorting of the mono- and difunctional phosphorus-based units making up the oligomeric chains is affected by neighboring units. Kinetic measurements demonstrated that the condensation polymerization is a complicated process involving considerable scrambling of terminal groups with bridging oxygen atoms.     

[Ph2P(O)CH2Im][F3B(μ‐OH)BF3]. Erste strukturanalytische Charakterisierung des Hexafluoro(μ‐hydroxo)diborat‐Ions [1]

[Ph₂P(O)CH₂Im][F₃B(μ‐OH)BF₃]. First Structural Characterization of the Hexafluoro(μ‐hydroxo)diborate Ion [1] The hexafluoro(μ‐hydroxo)diborate ion has been isolated as it's Ph₂P(O)CH₂Im salt [Im = 2‐(1, 3, 4, 5‐tetramethylimidazolio)] ( 2 ) through basic hydrolysis of [Ph₂P(OBF₃)CH₂Im]BF₄ ( 1 ). The crystal structure of 2 · CH₂Cl₂ reveals the presence of ion pairs linked by unsymmetrical O‐H‐O hydrogen bonds.     

Triorganoantimon- und Triorganobismutderivate von 2-Pyridincarbonsäure und 2-Pyridylessigsäure Kristall- und Molekülstrukturen von (C6H5)3Sb(O2C-2-C5H4N)2 und (CH3)3Sb(O2CCH2-2-C5H4N)2

Triorganoantimony and Triorganobismuth Derivatives of 2-Pyridinecarboxylic Acid and 2-Pyridylacetic Acid. Crystal and Molecular Structures of (C₆H₅)₃Sb(O₂C-2-C₅H₄N)₂ and (CH₃)₃Sb(O₂CCH₂-2-C₅H₄N)₂ Triorganoantimony and triorganobismuth dicarboxylates R₃M(O₂C-2-C₅H₄N)₂ (M = Sb, R = CH₃, C₆H₅, 4-CH₃OC₆H₄; M = Bi, R = C₆H₅, 4-CH₃C₆H₄) and (CH₃)₃Sb(O₂CCH₂-2-C₅H₄N)₂ have been prepared from (CH₃)₃Sb(OH)₂, R₃SbO (R = C₆H₅, 4-CH₃OC₆H₄), or R₃BiCO₃ (R = C₆H₅, 4-CH₃C₆H₄) and the appropriate heterocyclic carboxylic acid. Vibrational spectroscopic data indicate a trigonal bipyramidal environment of M the O(? C)-atoms of the carboxylate ligands being in the apical and three C atoms (of R) in the equatorial positions; in addition coordinative interaction occurs in the 2-pyridinecarboxylates between M and O(?C) of one and N of the other carboxylate ligand and in (CH₃)₃)Sb(O₂CCH₂-2-C₅H₄N)₂ between Sb and O(?C) of both carboxylate ligands. (C₆H₅)₃Sb(O₂C-2-C₅H₄N)₂/(CH₃)₃Sb(O₂CCH₂-2-C₅H₄N)₂ crystallize monoclinic [space group P2₁/c/P2₁/n; a = 892.6(9)/1043.4(6), b = 1326.9(6)/3166.2(18), c = 2233.1(9)/1147.5(7) pm, β = 99.74(8)°/97.67(5)° Z = 4/8; d(calc.) = 1.522/1.553 × Mg m^?3; V_cell = 2606.7 × 10⁶/3757.0 × 10⁶pm³, structure determination from 3798/4965 independent reflexions (F ≥ 4.0 σ(F))/(I ≥ 1.96 σ(I), R(unweighted) = 0.024/0.036]. Sb is bonding to three C₆H₅/CH₃ groups in the equatorial plane [mean distances Sb? C: 212.2(3)/208.7(6) pm] and two carboxylate ligands via O in the apical positions [Sb? O distances: 218.5(2), 209.9(2)/212.1(3), 213.2(3) pm]. In (C₆H₅)₃Sb(O₂C-2-C₅H₄N)₂ there is a short Sb? O(?C) and a short Sb? N contact [Sb? O: 272.1(2), Sb? N: 260.2(2) pm] and distoritions of the equatorial angles [C? Sb? C: 99.2(1)°, 158.2(1)°, 102.0(1).] and of the axial angle [O? Sb? O: 169.9(1)°], and in (CH₃)₃Sb(O₂CCH₂-2-C₅H₄N)₂, which contains two different molecules in the asym-metric unit, there are two Sb? O(?C) contacts [Sb? O, mean: 302.2(4), and 310.7(4)pm, respectively] and distortions of the equatorial angles [C? Sb? C: 114.5(2)°, 132.4(3)° 113.1(2)°, and 123.9(3)° 115.5(2)°, 120.6(3)°, respectively] and of the axial angles [O? Sb? O: 174,9(1)°, 177.9(1)°, respectively].     

Efficient dehydration of primary amides to nitriles catalyzed by phosphorus-chalcogen chelated iron hydrides

A series of phosphorus-chalcogen chelated hydrido iron (II) complexes 1–7 , (o-(R'₂P)-p-R-C₆H₄Y)FeH (PMe₃)₃ ( 1 : R = H, R' = Ph, Y = O; 2 : R = Me, R' = Ph, Y = O; 3 : R = H, R' = ⁱPr, Y = O; 4 : R = Me, R' = ⁱPr, Y = O; 5 : R = H, R' = Ph, Y = S; 6 : R = Me, R' = Ph, Y = S; 7 : R = H, R' = Ph, Y = Se), were synthesized. The catalytic performances of 1–7 for dehydration of amides to nitriles were explored by comparing three factors: (1) different chalcogen coordination atoms Y; (2) R' group of the phosphine moiety; (3) R substituent group at the phenyl ring. It is confirmed that 5 with S as coordination atom has the best catalytic activity and 7 with Se as coordination atom has the poorest catalytic activity among complexes 1 , 5 and 7 . Electron-rich complex 4 is the best catalyst among the seven complexes and the dehydration reaction was completed by using 2 mol% catalyst loading at 60 °C with 24 hr in the presence of (EtO)₃SiH in THF. Catalyst 4 has good tolerance to many functional groups. Among the seven iron complexes, new complexes 3 and 4 were obtained via the O-H bond activation of the preligands o-ⁱPr₂P(C₆H₄)OH and o-ⁱPr₂P-p-Me-(C₆H₄)OH by Fe(PMe₃)₄. Both 3 and 4 were characterized by spectroscopic methods and X-ray diffraction analysis. The catalytic mechanism was experimentally studied and also proposed.     

Heteroleptic ruthenium(II)/(III) 2,2′-bipyridine/1,10-phenanthroline complexes incorporating bidentate Schiff base N,O-ligands

Eight substituted bidentate Schiff base ligands HOC₆H₄CH=N-R (HL) (HL1: R = 4-ClC₆H₄, HL2: R = 2-ClC₆H₄, HL3: R = 4-NO₂C₆H₄, HL4: R = 4-MeC₆H₄, HL5: R = 2,6-Me₂C₆H₃, HL6: R = 2,46-Me₃C₆H₂, HL7: R = CH₂C₆H₅, and HL8: R = n-Pr) were synthesized by the typical condensation reaction. Interaction of cis-[Ru(bpy)₂Cl₂]?2H₂O (bpy = 2,2′-bipyridine) with one equivalent of HL ligand in the presence of KPF₆ afforded the cationic ruthenium(II) complexes of the type [Ru(bpy)₂(L)](PF₆) (1–8). The reaction of cis-[Ru(phen)₂Cl₂]?2H₂O (phen = 1,10-phenanthroline) and HL1 under similar condition gave complex [(phen)₂Ru(L)](PF₆) (1a). Treatment of cis-[Ru(phen)₂Cl₂]?2H₂O with two equivalents of HL in the presence of KPF₆ resulted in isolation of the cationic ruthenium(III) complexes of the type [Ru(phen)(L)₂](PF₆) (9-16). All complexes have been spectroscopically characterized. The structures of 1a?CH₂Cl₂, 2?½CH₂Cl₂, 3?CH₃CN, 5?½H₂O, 6, 12?½HOCH₂CH₂OH, 13?CH₃CN, 15?H₂O, and 16 have been determined by single-crystal X-ray diffraction.