Synthesis and structure of 1,2-diphosphacyclopentenes

Treatment of titanacyclobutenes with two equivalents of dichlorophenylphosphine affords diphosphacyclopentenes, two examples of which were structurally characterized by single-crystal X-ray diffraction analysis. The analogous reaction of a titanacyclobutene with dichlorophenylstibine affords the corresponding distibacyclopentene as well as a stibacyclobutene. © 1996 John Wiley & Sons, Inc.     

Synthesis and structure of 9-hydroxy-1,2-dicarba-closo-dodecaborane(11)

The oxidation of 1,2-C₂B₁₀H₁₂ (1) with 100% nitric acid was studied in two solvents (CH₂C1₂ and CCl₄). Under the action of superacid (CF3SO3H), the compound 9-HO-1,2-C₂B₁₀H₁₁ (2) gives the onium cation 9-H₂O⁺-1,2-C₂B₁₀H₁₁ involved in the salt [9-H₂O⁺-1,2-C₂B₁₀H_n]-CF₃SO₃^?, as demonstrated by ^uB NMR spectroscopy. The experimental and simulated ^uB NMR spectra of the cation 9-H₂O⁺-1,2-C₂B₁₀H₁₁ are in satisfactory agreement with each other. In the presence of a base, compound 2 is transferred from an ethereal solution to an aqueous alkaline solution giving the anion 9-O^?- 1,2-C₂B₁₀H₁₁. The structure of compound 2 was confirmed by ¹H, ¹¹B, ¹¹B¹H, ¹¹B-¹¹B COSY NMR spectroscopy, IR spectroscopy, and gas chromatography mass spectrometry and was additionally established by X-ray diffraction.

     

Synthesis and structure of heterometallic complexes (RhFe, CoFe) containing bridging 1,2-dicarba-closo-dodecarborane-1,2-dichalcogenolato ligands

The prototype hetero-binuclear complexes containing metal-metal bonds, {CpRh[E2C2(B10H10)]}[Fe(CO)3] (Cp = Cp* = eta 5-Me5C5, E = S(5a), Se(5b); Cp = Cp = eta 5-1,3-tBu2C5H3, E = S(6a), Se(6b)) and {CpCo[E2C2(B10H10)]}[Fe(CO)3] (Cp = Cp* = eta 5-Me5C5, E = S(7a), Se(7b); Cp = Cp = eta 5-C5H5, E = S(8a), Se(8b)) were obtained from the reactions of 16-electron complexes CpRh[E2C2(B10H10)] (Cp = Cp*, E = S(1a), Se(1b); Cp = Cp, E = S(2a), Se(2b)), CpCo[E2C2(B10H10)] (Cp = Cp*, E = S(3a), Se(3b); Cp = Cp, E = S(4a), Se(4b)) with Fe(CO)5 in the presence of Me3NO. The molecular structures of {Cp*Rh[E2C2(B10H10)]}[Fe(CO)3] (E = S(5a), Se(5b)), {CpRh[S2C2(B10H10)]}[Fe(CO)3] (6a) {Cp*Co[S2C2(B10H10)]}[Fe(CO)3] (7a) and {CpCo[S2C2(B10H10)]}[Fe(CO)3] (8a) have been determined by X-ray crystallography. All these complexes were characterized by elemental analysis and IR and NMR spectra.     

Synthesis and structure of novel 1,2-dihydro-phthalazine containing betaines

1,2-Dihydro-2-(4,5-dihydroimidazol-2yl)phthalazin-1-ol 1 reacts exothermically with dialkyl acetylenedicarboxylates to give 3-[2-(4,5-dihydro-1H-imidazol-3-iurn-2-yl)-1,2-dihydro-1-phthalazin]-1,4-dialkoxy-1,4-dioxo-2-buten-2-olates 7 and 8 . Enolic ester compounds underwent further transesterification reactions with formation of the betaines 9 and 10 . The unequivocal structural assignement of these compounds was achieved by spectroscopic ¹H and ¹³C nmr methods as well as X-ray analysis of 7 .     

Synthesis and structure of tetrahydro-1,2-oxazine-n-dithiocarboxylic acid esters

New tetrahydro-1,2-oxazine-N-dithiocarboxylic acid esters were synthesized, and their structures were investigated by IR and PMR spectroscopy and mass spectrometry.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 454–458, April, 1976.     

Synthesis and structure determination of N-(alkoxycarbonylsulfenyl)-s-triazine herbicides

Various 2-substituted-4,6-bis(alkylamino)-1,3,5-triazines, 1 , have been found to react with alkoxycarbonylsulfenyl chlorides, 2 , to give the title compounds, 3 . The structural characterization of 3a in the solid state by single X-ray crystallographic analysis established that it is the isomer wherein the methoxycarbonylthio group is attached to the less sterically hindered, exocyclic nitrogen bearing the ethyl group.     

Synthesis and structure of the first 1,2sigma5-selenaphosphirane

A 1,2sigma5-selenaphosphirane bearing the Martin ligand was synthesized. Its structure in both the solid and the solution state was established by X-ray crystallographic analysis and NMR measurements, respectively. The selenaphosphirane has a polar P-Se bond, and the selenium atom is negatively charged. In the solution state, the degree of polarization of the P-Se bond depends on the acceptor number of the solvents.     

Synthesis and X-ray crystal structure of tetraethylammonium bis[1,2-di(carbomethoxy)ethane-1,2-dithiolato]oxotechnetate(V)

Summary The (NEt₄)⁺[TcO{SCH(CO₂Me)CH(CO₂Me)}₂]^– compound has been prepared from technetium(V) gluconate and characterized by single crystal x-ray structural analysis (R factor=0.065).The compound crystallizes in the monoclinic space groupP2₁/c witha=12.722(3),b=13.820(4) andc=18.213(5) Å, =107.13(4)° andZ=4. In the complex the technetium atom is close to the center of the base of a square pyramid in which the oxo oxygen is at the apex and the four sulfur atoms form the basal plane. The Tc-S distances average 2.316 Å. The Tc=O distance is 1.672(6) Å. Considerations about the osteotropic behaviour of DMSA labelled with⁹⁹Tc are deduced from the reported results.     

Synthesis and structure of new substituted 2-dicyanomethylene-1,2-dihydropyridines

The synthesis of substituted 2-dicyanomethylene-1,2-dihydropyridines 3b-c and 2-dicyanomethylene-2,3,4,5-tetrahydropyridine 4 is accomplished from malononitrile dimer and propenenitriles 2 . All structures were determined by nmr techniques; however to put our structural assignment for 6-amino-3-cyano-5-ethoxycarbonyl-2-dicyanomethylene-1,2-dihydropyridine 3d on a firm and unequivocal basis we decided to perform X-ray diffraction analysis of this compound.     

Synthesis and structure of 1,2-O-isopropylidene-α-D-glucofuranose 3,5-phenylcyclophosphonate

L. Ya. Karpov Scientific-Research Physical Chemistry Institute. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 3, pp. 67–73, May–June, 1991.     

Synthesis and crystal structure determination of Cl-substituted iridium(III) acetylacetonate

γ-Halogen-substituted iridium(III) acetylacetonates of general formula Ir(acacX)₃,where acacX = CH₃ -CO-CX-CO- CH₃,X =Br, I, were synthesized. The compounds are characterized by melting points and chemical analysis data for C, H, Br, and I. An X-ray diffraction analysis was performed for iridium(III) acetylacetonate and its y-substituted analogs, crystal data were obtained, and crystal structures were determined. The crystals are monoclinic;the structures are molecular. Crystal data: Ir(acac)3 _- IrO₆C₁₅H₂₁,a = 13.900(2), b = 16.440(3), c = 7.494(2) ?, γ =98.63(2)‡, V= 1693.2 ?³,space group P2₁/b,Z = 4, d_calc =1.92 g/cm³,sin θ/λ_max = 0.703, F_hkl = 2841, R = 0.044. Ir(acacBr)_3- IrBr₃O₆C₁₅H₁₈,a = 12.794(2), b = 15.753(2), c = 9.990(2) ? Β = 105.76(2)‡, V= 1937.6 ?³,space group P2₁/n,Z =4, d_calc =2.49 g/cm³, sinθ/λ_max = 0.702, F_hkl = 1748, R = 0.048. Ir(acacI)3- M₃O₆C₁₅H₁₈,a = 12.855(2), b = 10.136(2), c =16.338(3)?, Β = 104.6(2)‡, V=2059.8?³,space group P2₁/n, Z =4, d_calc = 2.79g/cm³, θ_max =25‡, F_hkl = 2817, R =0.032. The Ir..Ir distances were estimated to be > 7.49 ? for Ir(acac)3 and > 8.10 ? for Ir(acacBr)3 and Ir(acacl)₃.If the estimate is limited to 10 ?, the intermolecular coordination number (ICN) in the structures is 10. Translated fromZhurnal Struktumoi Khimii, Vol. 40, No. 2, pp. 331–339, March–April, 1999     

Synthesis and structure of some zinc and cadmium 1,2-cyclohexanedione dioximines

Russian Journal of Coordination Chemistry - The complexes [Zn(CH3COO)2(NioxH2)(DMF)(H2O)] (I), [Cd(CH3COO)2-(NioxH2)(DMF)(H2O)] (II), [Zn(CH3COO)2(NioxH2)(S-Nia)(H2O)] · DMF (III),...     

Synthesis,structure and spectroscopic characterization of 1,2-bis-(2,4,6-trimethylbenzylideneamino)ethanedichloropalladium(II)

The structure of 1,2-bis(2,4,6-trimethylbenzylideneamino)ethanedichloropalladium(II) was determined by X-ray diffraction methods. The structure derived from NMR and IR spectra and elemental analysis is consistent with it. The complex is orthorhombic, space group Pcab, with a?=?14.8662(12), b?=?15.0861(13), c?=?20.6255(14)?Å, V?=?4625.7(6)?ų and Z?=?8. In the lattice, there exists a weak C–H?···?Cl hydrogen bond.     

The transformation of Sn(ND3)2F4 into Sn(ND2)2F2. Synthesis and neutron crystal structure determination of Sn(ND2)2F2

Diamido-difluoro-tin Sn(ND₂)₂F₂ can be produced by ammonolysis from (NH₄)₂SnF₆ at 633 K. The compound is a product formed from Sn(ND₃)₂F₄ during the ammonolysis reaction. Sn(ND₂)₂F₂ isostructural with Sn(NH₂)₂F₂ crystallizes in space group C2/m with lattice constants a = 1072.92(7), b = 325.97(1) pm, c = 505.79(4) pm and β = 105.713(6) ° (V = 170.28(1) ·10⁶ pm³) containing two formula units per unit cell. Data refinement by the Rietveld method of neutron time-of-flight data collected at POLARIS yields a weighted profile R-value R_wp = 0.022. Tin is octahedrally coordinated by two fluorine atoms and four amido groups. The octahedra are connected to one-dimensional chains by edge sharing. The ND₂ groups are in the bridging position whilst the fluorine atoms are terminal. Nearly linear (175.2(4) °) and angular (134.35(8) °) N-D···F hydrogen linkages connect the chains.     

Synthesis and crystal structure determination of tetramethylammonium auride

Tetramethylammonium auride, the first compound of negatively charged gold with a non-metal cation, has been synthesised by cation exchange in liquid ammonia; it is isostructural to the corresponding bromide which further illustrates the similarities between the halogens and gold.