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1.
Metal Derivatives of Molecular Compounds. IX. Bis(1,2-dimethoxyethane- O,O′ )lithium Phosphanide, Arsanide, and Chloride – Three New Representatives of the Bis(1,2-dimethoxyethane- O,O′ )lithium Bromide Type Experiments to obtain thermally unstable lithium silylphosphanide at –60 °C from a 1,2-dimethoxyethane solution resulted in the isolation of its dismutation product bis(1,2-dimethoxyethane-O,O′)lithium phosphanide ( 1 ). The homologous arsanide 2 precipitated after a frozen solution of arsane in the same solvent had been treated with lithium n-butanide at –78 °C. Unexpectedly, too, the analogous chloride 3 and bromide 4 were formed in reactions of 1-chloro-2,2-bis(trimethylsilyl)-1λ3-phosphaethene with (1,2-dimethoxyethane-O,O′)lithium bis(trimethylsilyl)stibanide and of lithium 1,2,3,4,5-pentaphenyl-2,3-dihydro-1λ3-phosphol-3-ide with ω-bromostyrene, respectively. The monomeric complexes 1 {–100 ± 3 °C; a = 1391.1(4); b = 809.8(2); c = 1249.1(3) pm; β = 102.84(2)°}, 2 {–100 ± 3 °C; a = 1398.3(4); b = 819.8(3); c = 1258.5(4) pm; β = 103.35(2)°} and 3 {–100 ± 3 °C; a = 1308.4(2); b = 788.2(1); c = 1195.6(1) pm; β = 95.35(1)°} crystallize in the monoclinic space group C2/c with four solvated ion pairs in the unit cell; they are isotypic with bis(1,2-dimethoxyethane-O,O′)lithium bromide ( 4 ) {–73 ± 2 °C; a = 1319.0(2); b = 794.1(1); c = 1214.3(2) pm; β = 96.22(1)°}, already studied by Rogers et al. [13] at room temperature. The neutral complexes show a trigonal bipyramidal configuration of symmetry C2, pnicogenanide or halide anions occupying equatorial sites {Li–P 260.4(4); Li–As 269.8(6); Li–Cl 238.6(7); Li–Br 256.3(10) pm} and the chelate ligands spanning equatorial and axial positions {Li–Oeq 205.4(4) to 207.4(4); Li–Oax 208.9(3) to 215.5(2) pm}. The coordination within the (dme)2Li fragment, the Li–X distances (X = P, As, Cl, Br), the structure of the chelate rings, and the packing of the neutral complexes are discussed in detail.  相似文献   

2.
Metal Derivatives of Molecular Compounds. VI. Lithium and (Tetrahydrofuran)lithium Cyanotrimethylsilylamide — Syntheses and Structures At different temperatures N,N′-bis(trimethylsilyl)carbodiimide ( 1 ) and lithium methanide react either under addition or substitution. When compound 1 , however, is treated at ?40°C with an equimolar amount of (1,2-dimethoxyethane-O,O′)lithium phosphanide ( 2 ) in 1,2-dimethoxyethane, only exchange of one trimethylsilyl group versus lithium is observed and in addition to phosphane and tris(trimethylsilyl)phosphane a very pure lithium derivative insoluble in n-pentane can be isolated. The vibrational spectra prove the compound to be lithium cyanotrimethylsilylamide ( 3 ). Recrystallization from tetrahydrofuran (+40/+20°C) yields (tetrahydrofuran)lithium cyanotrimethylsilylamide ( 3 ′). As shown by an X-ray structure analysis {C2/c; a = 2 261.1(5); b = 1 106.4(2); c = 1 045.9(2) pm; β = 113.63(1)°; Z = 8 formula units}, compound 3 ′ is polymeric in the solid state. Coordinative Li? N2′ bonds allow a head-to-tail addition of two monomeric units each to give an eight-membered heterocycle with two linear N1? C2≡N2 fragments (N1? C2 126.1; C2≡N2 117.5; N1? Si 171.4; Li? N1 203.2; Li? N2′ 206.1 pm; C2? N1? Li 109.0; N1? Li? N2′ 115.9; N2≡C2? N1 177.2°). Forming planar four-membered Li? N2? Li? N2 rings (Li? N2″″ 198.3 pm; Li′? N2? Li″ 80.3; N2′? Li? N2″″ 99.5°) these heterocycles polymerize to slightly folded tapes.  相似文献   

3.
Metal Derivatives of Molecular Compounds. VII. Bis[1,2-bis(dimethylamino)ethane-N,N′]lithium Disilylphosphanide — Synthesis and Structure Crystalline lithium phosphanides studied so far show a remarkably high diversity of structure types dependent on the ligands at lithium and the substituents at phosphorus. Bis[1,2-bis(dimethylamino)ethane-N,N′]lithium disilylphosphanide ( 1 ) discussed here, belongs to the up to now small group of compounds which are ionic in the solid state. It is best prepared from silylphosphane by twofold lithiation with lithium dimethylphosphanide first and subsequent monosilylation with silyl trifluoromethanesulfonate, followed by complexation. As found by X-ray structure determination (wR = 0.038) on crystals obtained from diethyl ether {monoclinic; space group P21/c; a = 897.8(1); b = 1 673.6(2); c = 1 466.8(1) pm; β = 90.73(1)° at ?100 ± 3°C; Z = 4 formula units}, the lithium cation is tetrahedrally coordinated by four nitrogen atoms of two 1,2-bis(dimethylamino)ethane molecules. Characteristic parameters of the disilylphosphanide anion are a shortened average P? Si bond length of 217 pm (standard value 225 pm) and a Si? P? Si angle of 92.3°.  相似文献   

4.
(O,O′)-Diorganodithiophosphatophenyltellurium(II)- and Tris[(O,O′)-diorganodithiophosphato]phenyltellurium(IV) Compounds; Crystal Structure of Tris[(O,O′)-diphenyldithiophosphato]phenyltellur(IV) The title compounds are available by reaction of trichlorophenyltellurium(IV) respectively iodophenyltellurium(II) with the sodium or ammonium salts of (O,O′)-diorganodithiophosphorus acids in various solvents. The resulting tellurium(IV) compounds have a pronounced tendency towards reductive elimination of bis[(O,O′)-diorganothiophosphoryl]disulfanes [S2P(OR)2]2 in solution. In contrast, the tellurium(II) compounds are stable, although they are disintegrated to diphenylditellane and [S2P(OR)2]2 on prolonged standing in chlorinated hydrocarbons. Crystals of tris[(O,O′)-diphenyldithiophosphato]phenyltellurium(IV) are monoclinic (space group P21/c) with the cell constants: a = 1 039.2(1), b = 1 037.9(3), c = 4 205.0(1) pm, β = 95.273(1)°, V = 4 516.42(9)X106 pm3, Z = 4. The compound appears to be monomeric in the solid state forming a distorted pentagonal bipyramid. The stereochemical influence of the lone pair of electrons causes the axial (i. e. C1? Te? S4) angle to be 156.6(1)° rather than the theoretical 180°.  相似文献   

5.
Alkylidynephosphines and -arsines. III. [(dme)Li]3As7 – Synthesis and Constitution of a Compound with Nortricyclane Structure While treatment of bis(tetrahydrofuran)lithium bis(trimethylsilyl)phosphanide with dimethyl carbonate in 1,2-dimethoxyethane results in formation of methoxytrimethylsilane and the λ3-phosphaalkyne (dme)2Li–O–C≡P [2], a similar reaction of the corresponding arsanide gives the neutral complex [(dme)Li]3As7 ( 1 a ) together with carbon monoxide. From a cooled solution of mostly 1,2-dimethoxyethane and small amounts of diethyl ether amber rods of the co-crystallizate 1 a · OEt2 precipitate; a detailed analysis of the data record showed that they are twinned by reticular merohedry with apparent hexagonal symmetry. A subsequent x-ray structure determination in space group P21/n (a1 = 1123.0(2); b = 1485.5(3); c1 = 1945.1(4) pm; β = 90.00(3)° at –100 ± 3 °C; Z = 4 formula units; wR2 = 0.280) revealed an almost hexagonal packing of neutral complexes with relatively mobile diethyl ether molecules in channels of the structure. Two negatively charged arsenic atoms each of the heptarsanortricyclane skeleton coordinate to a [(dme)Li]+ cation; average bond lengths and angles (Asa–Ase 240.7; Ase–Asb 235.3; Asb–Asb 249.8 pm; Ase–Asa–Ase 101.0°; Asa–Ase–Asb 99.6°; Ase–Asb–Asb 105.1°; Asb–Asb–Asb 60.0°) are similar to those of analogous compounds. Ab initio calculations were performed on the model systems As73– ( 2 ) and As7H3 ( 3 ) in order to explain striking trends in characteristic parameters of anionic or molecular heptarsanortricyclane skeletons, respectively.  相似文献   

6.
Tl4Pd3Cl10 – A Compound with a New [(PdCl2Cl2/2)4]4– Group Single crystals of Tl4Pd3Cl10 can be obtained by hydrothermal synthesis. They show tetragonal symmetry with lattice parameters a = 15.956(1) Å and c = 14.146(1) Å, Z = 8 and space group I42d (No. 122). The atomic arrangement of Tl4Pd3Cl10 is explored by X‐ray crystal structure analysis. Tl4Pd3Cl10 is the first example of a new structural type with a hitherto not isolated tetramer [(PdCl2Cl2/2)4]4– group.  相似文献   

7.
Polysulfonylamines. XCIV. Molecules with Unusually Long N(sp2)–Si(sp3) Bonds: Synthesis and Crystal Structures of 1,2-Benzenedisulfonylaminosilanes The following compounds were obtained by metathesis of silver 1,2-benzenedisulfonimide (AgZ) with the appropriate chlorosilanes: ZSiMe3 ( 4 ), ZSinPr3, ZSiMe2nBu, ZSiMe2(CMe2–CHMe2) ( 7 ), (Z)2SiMe2 ( 8 ). In the crystal structures of 4 (monoclinic, space group P21/n), 7 (monoclinic, P21/c) and 8 (monoclinic, P21/n), which were determined by low-temperature X-ray diffraction, the molecules adopt the N-silyl form and display unusually long bonds between the trigonal-planar N and the tetrahedrally coordinated Si atoms ( 4 : 182.6, 7 : 184.1, 8 : 177.8 and 180.5 pm). For 7 in CDCl3 solution, 1H and 13C NMR data indicate N,O-silylotropy. The solid state structures of molecules 4 and 7 strongly suggest that the N–Si bond lengthening in N,N-disulfonylated aminosilanes is mainly induced by the π-acceptor character of the SO2 groups and not by the occasionally observed coordination expansion of the Si atom through short intramolecular O…Si contacts.  相似文献   

8.
On a New Copper Cobalt Borate Oxide with Isolated B2O5 Units: Cu2Co(B2O5)O Single crystals of a new compound with the empirical formula Cu2CoB2O6 were obtained by using a B2O3 flux technique. X-ray single crystal technique led to a new structure type. Cu2CoB2O6 crystallizes monoclinic, space group C-P21/c (No. 14); a = 3.2250(6); b = 14.847(1); c = 9.1171(6) Å; β = 93.67°; Z = 4. All metal sites are octahedrally coordinated and form a two dimensional framework consisting of edge sharing octahedra ribbons. In addition one observes isolated B2O5-units and oxygen which is not coordinated to boron. The far relation to the crystal structure of the mineral Warwickite is illustrated.  相似文献   

9.
The preparations of [(C6H5O)2PS]2NH ( SS ) and its Pd complex [Pd{C6H5O2P(S)NP(S)(OC6H5) 2}2] ( PDSS ) are described. The compounds were characterized by elemental analysis, NMR, and mass spectra and X-ray structure analysis. The structure of SS contains two independent molecules in an asymmetric unit which are joined into dimers via N …? H …? S hydrogen bonds. SS is a Br?nsted acid And reacts with PdII to a neutral chelate complex. The structure of PDSS is composed of isolated molecules with Pd atom in the center of symmetry. The Pd atom is coordinated by 4 S atoms in a distorted square-planar arrangement with average distance Pd? S 2.345(6) Å and an angle S? Pd? S 98.29(4)°.  相似文献   

10.
11.
Alkylidynephosphanes and -arsanes. I [P ≡ C? S]?[Li(dme)3]+ – Synthesis and Structure O,O′-Diethyl thiocarbonate and bis(tetrahydrofuran)-lithium bis(trimethylsilyl)phosphanide dissolved in 1,2-dimethoxyethane, react below 0°C to give ethoxy trimethylsilane and tris(1,2-dimethoxyethane-O,O′)lithium 2λ3-phosphaethynylsulfanide – [P≡C? S]? [Li(dme)3]+ – ( 1a ). Apart from bis(trimethylsilyl)sulfane or carbon oxide sulfide, dark red concentrated solutions of λ3-phosphaalkyne 1 are also obtained from reactions of carbon disulfide with bis(tetrahydrofuran)-lithium bis(trimethylsilyl)phosphanide or with the homologous lithoxy-methylidynephosphane ( 2 ) [1]. The ir spectrum shows two absorptions at 1762 and 747 cm?1 characteristic for the P≡C and C? S stretching vibrations. The nmr parameters {δ(31P) ? 121.3; δ(13C) 190.8 ppm; 1JCP 18.2 Hz} resemble much more values of diorganylamino-2λ3-phosphaalkynes than those of bis(1,2-dimethoxyethane-O,O′)lithoxy-methylidyne-phosphane ( 2a ). As found by an X-ray structure analysis (P21/c; a = 1192.6(16); b = 1239.1(19); c = 1414.8(26) pm; β = 105.91(13)° at ?100 ± 3°C; Z = 4 formula units; wR = 0.064) of pale yellow crystals (mp. + 16°C) isolated from the reaction with O,O′-diethyl thiocarbonate, the solid is built up of separate [P≡C? S]? and [Li(dme)3]+ ions. Typical bond lengths and angles are: P≡C 155.5(11); C? S 162.0(11); Li? O 206.4(17) to 220.3(20) pm; P≡C? S 178.9(7)°.  相似文献   

12.
Synthesis and Crystal Structure of Te3O3(PO4)2, a Compound with 5‐fold Coordinate Tellurium(IV) Polycrystalline Te3O3(PO4)2 is formed during controlled dehydration of (Te2O3)(HPO4) with (Te8O10)(PO4)4 as an intermediate product. Colourless single crystals were prepared by heating stoichiometric amounts of the binary oxides P2O5 und TeO2 in closed silica glass ampoules at 590 °C for 8 hours. The crystal structure (P21/c, Z = 4, α = 12.375(2), b = 7.317(1), c = 9.834(1)Å, β = 98.04(1)°, 1939 structure factors, 146 parameters, R[F2 > 2σ(F2)] = 0.0187, wR2(F2 all) = 0.0367) was determined from four‐circle diffractometer data and consists of [TeO5] polyhedra und PO4 tetrahedra as the main building units. The framework structure is made up of cationic zigzag‐chains of composition [Te2O3]2+ which extend parallel to [001] and anionic [Te(PO4)2]2— units linked laterally to these chains. This leads to the formation of [Te2O3][Te(PO4)2] layers parallel to the bc plane which are interconnected via weak Te‐O bonds.  相似文献   

13.
Reaction of 1,′, 3,3′-Tetrakis(dimethylamino)-1λ5,3λ5-diphosphete with S? H Acidic Compounds. Reaction of 1,′,3,3′-tetrakis(dimethyl-amino)-1λ5,3λ5-diphosphete ( 1 ) with hydrogen sulfide yields bis(dimethylamino)thiophosphonylmethylidene-methyl-bis(dimethylamino)phosphorane ( 5 ).Water eliminates dimethylamine from 5 and forms bis(dimethyl-amino)thiophosphonyl-methyl(dimethylamino)phosphonylmethylene 6 . The reaction of 1 with ethylmercaptane yields the 2,4-bis(ethylthio)-derivative of 1 , i.e. compound 8 and bis(dimethylamino)phosphanylmethylidene-methyl-bis(dimethylamino)phosphorane ( 9 ), which is also formed from 1 and 2,4,6-trimethylphenylphosphane. Thiophenol protonates 1 to give the corresponding cation which is isolated as its thiophenolate, 10 . Properties, nmr and mass spectra of 5, 6 and 8 – 10 are described and discussed.  相似文献   

14.
5‐(2‐Cyanoethyl)‐1,1′‐biphenyl‐2‐carboxylates were prepared by regioselective formal [3+3] cyclocondensations of 1,3‐bis[(trimethylsilyl)oxy]buta‐1,3‐dienes.  相似文献   

15.
Metal Derivatives of Molecular Compounds. IV Synthesis, Structure, and Reactivity of Lithium [Tris(trimethylsilyl)silyl]tellanide · DME Lithium tris(trimethylsilyl)silanide · 1,5 DME [3] and tellurium react in 1,2-dimethoxyethane to give colourless lithium [tris(trimethylsilyl)silyl]tellanide · DME ( 1 ). An X-ray structure determination {-150 · 3·C; P21/c; a = 1346.6(4); b = 1497.0(4); c = 1274.5(3) pm; β = 99.22(2)·; Z = 2 dimers; R = 0.030} shows the compound to be dimeric forming a planar Li? Te? Li? Te ring with two tris(trimethylsilyl)silyl substituents in a trans position. Three-coordinate tellurium is bound to the central silicon of the tris(trimethylsilyl)silyl group and to two lithium atoms; the two remaining sites of each four-coordinate lithium are occupied by the chelate ligand DME {Li? Te 278 and 284; Si? Te 250; Li? O 200 pm (2X); Te? Li? Te 105°; Li? Te? Li 75°; O? Li? O 84°}. The covalent radius of 154 pm as determined for the DME-complexed lithium in tellanide 1 is within the range of 155 ± 3 pm, also characteristic for similar compounds. In typical reactions of the tellanide 1 [tris(trimethylsilyl)silyl]tellane ( 2 ), methyl-[tris(trimethylsilyl)silyl]tellane ( 4 ) and bis[tris(trimethylsilyl)silyl]ditellane ( 5 ) are formed.  相似文献   

16.
Six arsenic-containing β-D -ribofuranosides, including the naturally occurring (2′R)-dimethyl[1-O-(2′,3′-dihydroxypropyl)-5-deoxy-β-D -ribofuranos-5-yl]arsine oxide, were prepared in multi-step reactions from D -ribose and tetramethyldiarsine. The synthetic procedure uses the early substitution of the hydroxy group with bromine at C5, subsequent attachment of a chiral three-carbon aglycone at C1, and final delivery of arsenic at C5. The synthesis provides a viable route for the preparation of multigram quantities of the natural product.  相似文献   

17.
InIII-Phthalocyanines: Synthesis, Properties, and Crystal Structure of Tetra(n-butyl)ammonium-cis-di(nitrito-O,O')phthalocyaninato(2–)indate(III) [In(Cl)Pc2?] reacts with (nBu4N)NO2 in acetone yielding green-blue (nBu4N)cis[In(NO2)2Pc2?], which crystallizes in the monoclinic space group P21/n (No. 14). Both nitrite anions are coordinated as chelating nitrito-O,O'(NO2) ligands to InIII in cis-geometry. Consequently InIII is octa-coordinated within a distorted “quadratic” antiprism and directed towards the Pc2?-ligand. One of the NO2 ligands has equivalent N? O bonds similar to free nitrite, while the other has asymmetric N? O bonds. Both (In,O,N,O) rings are approximately planar with a dihedral angle of 80°. The Pc2? ligand is distorted in an asymmetrically convex manner. Partially overlapping pairs of Pc2? ligands related by an inversion center form double layers, which are separated by layers containing the (nBu4N)+ cations. The cyclic voltammogram shows three electrode processes, which are assigned to the redox pairs: Pc3?/Pc2? (?0.94 V) < InI/InIII (-0.78 V) < Pc2?/Pc? (0.64 V). The UV-VIS-NIR spectra and vibrational spectra are discussed.  相似文献   

18.
Synthesis and Crystal Structure of meso-(1,2,3-Tricyclohexyltriphosphane-1,3-diyl)zirconocene(IV), Cp2 (Cp = η5?C5H5, Cy = C6H11) Cp2ZrCl2 reacts with Li(THF)2PHCy (Cy = C6H11) to yield the metallacyclic compound Cp2 1. , The 31P{1H} NMR spectrum of 1 , shows a coupling pattern for an A2X system, indicating the presence of only the meso-forms in solution, which are also present in the solid state. 1 , crystallizes in the monoclinic space group P21/n (No. 14) with a = 12.984(8), b = 9.241(7), c = 23.05(1) Å, β = 93.48(4)°, V = 2760.1 Å3 and four formula units in the unit cell (2718 independent observed reflections, R = 7.3%). The central ZrP3 ring in 1 , is almost planar. The Zr? P bond lengths of 2.618(4) and 2.628(4) Å are nearly identical.  相似文献   

19.
Synthesis and Structure of Cs11[(WN2,5O1,5)2](N3)2, a Cesium Oxo Nitrido Monotungstate(VI) Azide Cs11[(WN2,5O1,5)2](N3)2 results from the reaction of a mixture of CsNH2, W and WO3 at 620 °C in autoclaves. It crystallizes monoclinic in the space group C2/m with the lattice parameters a = 12.421(4) Å, b = 11.568(6) Å, c = 10.516(4) Å, β = 118.71(3)° and Z = 4. The crystal structure is built up by isolated tetrahedra [WX4] with X = N, O, which are connected by cesium cations. Between the cesium ions lie azide ions separated from the anions [WX4]. The tungsten atoms and azide ions together build up the motif of a distorted arrangement of the CsCl structure type.  相似文献   

20.
2‐Amino‐3‐hydroxypyridinium dioxido(pyridine‐2,6‐dicarboxylato‐κ3O2,N,O6)vanadate(V), (C5H7N2O)[V(C7H3NO4)O2] or [H(amino‐3‐OH‐py)][VO2(dipic)], (I), was prepared by the reaction of VCl3 with dipicolinic acid (dipicH2) and 2‐amino‐3‐hydroxypyridine (amino‐3‐OH‐py) in water. The compound was characterized by elemental analysis, IR spectroscopy and X‐ray structure analysis, and consists of an anionic [VO2(dipic)] complex and an H(amino‐3‐OH‐py)+ counter‐cation. The VV ion is five‐coordinated by one O,N,O′‐tridentate dipic dianionic ligand and by two oxide ligands. Thermal decomposition of (I) in the presence of polyethylene glycol led to the formation of nanoparticles of V2O5. Powder X‐ray diffraction (PXRD) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of the synthesized powder.  相似文献   

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