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1.
The crystal and molecular structures of the title compound, the first for a complex of the type [RuCp*(η6‐C8‐ring)]+, is presented, the material being obtained serendipitously from a reaction between RuCl(cod)Cp* and 1‐ferrocenylbuta‐1,3‐diyne in the presence of ZnCl2. <Ru‐C(Cp*)> (2.21 Å) is appreciably longer than in RuCp*2 (2.18 Å) and similar to the value for the Ru‐η6 component (2.22 Å).  相似文献   

2.
On triplet sensitization (E)- 5 gives (Z)- 5 and isomerizes via C(δ), O-bond cleavage to the cyclobutanone 6 and the conjugated γ-ketoester 7 . - On singulet excitation 6 undergoes decarbonylation and yields the bicyclo [4.1.0]heptane 8 . However, on triplet sensitization 6 is converted to the isomeric tricyclononane 9 by a stereospecific oxa-di-π-methane rearrangement. The structure of 9 is determined by X-ray analysis of the p-nitrobenzoate 15: a = 10.573, b = 14.707, c = 13.494 Å, β = 112.40°, P21/n, Z, = 4.  相似文献   

3.
The crystal and molecular structure of 3-oxo-17β-acetoxy-Δ4-14α-methyl-8α, 9β, 10α, 13α-estrene, C21H30O3, has been determined by X-ray diffraction analysis. The crystals belong to the orthorhombic space group P212121, with the cell dimensions a = 12.093 Å, b = 19.667 Å, c = 7.746 Å; Z = 4. Intensity data were collected at room temperature with an automatic four-circle diffractometer. The structure was solved by direct methods and the parameters were refined by least-squares analysis. All the hydrogen atoms were included in the refinement. The final R value was 0.038 for 1413 observed reflections. The conformation of ring A is intermediate between a half-chair and a 1, 2-diplanar form. The hydrogens at C(9) and C(10) are anti, the B/C ring junction is trans, and rings B and C adopt chair conformations. Ring D is cis fused and is halfway between C2 and Cs forms.  相似文献   

4.
The reaction of Cu(AcO)2 · H2O and tridentate β-iminoketone ligands yielded four new copper complexes: acetato{4-{[2-(dimethylamino)ethyl]amino}pent-3-en-2-onato}copper(II) ( 1 ), triacetato{4-{[3-(dimethylamino)-propyl]amino}pent-3-en-2-onato}dicopper(II) ( 2 ), {4-{[2-(dimethylamino)ethyl]amino}-1,1,1-trifluoropent-3-en-2-onato}( trifluoroacetato)copper(II) ( 3 ), and pentaacetato{4-{[3-(dimethylamino)propyl]amino}-1,1,1-trifluoropent-3-en-2- onato}tricopper(II) ( 4 ). All compounds were coloured and air-stable solids. The crystal structures of 1 and the dioxane adduct of 3 , μ-(1,4-dioxane)bis{{4-{[2-(dimethylamino)ethyl]amino}-1,1,1-trifluoropent-3- en-2-onato}(trifluoroacetato)copper(II)} ( 3a ), were determined. Complex 1 consists of dimeric units [{Cu(AcO)L}2] in the solid state (L = β-iminoketonato ligand). In 3a , two [Cu(CF3COO)L] are linked via the O-atoms of the coordinated solvent 1,4-dioxane. Compound 1 crystallized in the monoclinic space group P21/n with a formula unit in a cell having the dimensions a = 11.152(6)Å, b = 10.104(3)Å, c = 11.805(7)Å, and β = 99.02(4)Å, and compound 3a crystallized in the triclinic space group P1 with a formula unit in a cell having the dimensions a = 8.709(3)Å, b = 9.439(4)Å, c = 12.395(3)Å, α = 67.57(3)°, β = 77.01(2)°, and β = 84.17(3)°. Mass spectra (MS), thermal analysis (DTA/TG), and evaporation-rate measurements are reported for all compounds. The influence of fluorination on the structure and volatility will be discussed.  相似文献   

5.
α-Phenyl-4-nitrobenzenemethanol ( 3 ) reacted with 1 M sodium hydroxide to yield 4, 4′-dibenzoyl-azoybenzene ( 5 ) (51%), 4-hydroxy-4′-benzoylazobenzene ( 6 ) and benzoic acid (12% each), and smaller amounts of 4-aminobenzophenone and 4-nitrobenzophenone. Both α-phenyl-2-nitrobenzenemethanol ( 9 ) and 3, 5-dimethyl-4-nitrobenzenemethanol ( 10a ) did not react with 1 M sodium hydroxide, presumably due to steric hindrance. α-(p-Nitrophenyl)-4-pyridinemethanol ( 14 ) and its N-oxide 11 with 1 M sodium hydroxide yielded 4,4′-diaroylazoxybenzenes 15a and 12a , respectively, 4,4′-diaroylazobenzenes 15b and 12b , respectively, as well as 4-hydroxy-4′-aroylazobenzenes 16 and 13 , respectively. The relative reaction rates were 11 > 14 > 3 . Studies with 11 showed that the nitro group is involved in the redox reaction in preference to the N-oxide group.  相似文献   

6.
Selective n → π* excitation of the α,β-unsaturated enone 1 in hydrocarbon solvents resulted in a deconjugation reaction to 3 , reminiscent of results previously reported for similar systems [2], whereas the photoreactivity of 1 in alcohol solvents at wavelengths >3400 Å was so small that only product 4 has been identified as yet. Excitation of the π → π* transition of compound 1 at 2537 Å initiated additional phototransformations which could not be effected by irradiation in the first absorption band. The [4.4.3]-12-oxapropellane derivative 2 was identified as one of the two new major photo-isomers. A 6:8 mixture of products 2 and 3 , plus about 1 part of an isomer of still unknown structure (see however, the Addendum), were readily formed in hydrocarbon solvents, and a 1:10 ratio of 2 and the unknown product was obtained in methanol. Abstraction of a methoxyl hydrogen by the ketone oxygen is proposed to account for the primary photochemical step in the cyclization to 2 . A hydrogen-deuterium isotope effect of 2.7 was observed in a competitive experiment using 1 and 1-d 6. 34% of one deuterium atom were exchanged for hydrogen when 1-d 6 was photolyzed to 2-d 6 in t-butyl alcohol, which suggests an intermediate of type a in the pathway 1 → 2 possessing a readily exchangeable proton. Steric considerations would require a strongly distorted, non-planar excited-state geometry of the enone group of 1 for the oxygen to approach a methoxyl hydrogen. The transformation 1 → 2 represents a novel reaction type in photochemical processes of conjugated enones which are specifically induced by π → π* excitation only.  相似文献   

7.
Methyl β‐D‐mannopyranosyl‐(1→4)‐β‐D‐xylopyranoside, C12H22O10, (I), crystallizes as colorless needles from water, with two crystallographically independent molecules, (IA) and (IB), comprising the asymmetric unit. The internal glycosidic linkage conformation in molecule (IA) is characterized by a ϕ′ torsion angle (O5′Man—C1′Man—O1′Man—C4Xyl; Man is mannose and Xyl is xylose) of −88.38 (17)° and a ψ′ torsion angle (C1′Man—O1′Man—C4Xyl—C5Xyl) of −149.22 (15)°, whereas the corresponding torsion angles in molecule (IB) are −89.82 (17) and −159.98 (14)°, respectively. Ring atom numbering conforms to the convention in which C1 denotes the anomeric C atom, and C5 and C6 denote the hydroxymethyl (–CH2OH) C atom in the β‐Xylp and β‐Manp residues, respectively. By comparison, the internal glycosidic linkage in the major disorder component of the structurally related disaccharide, methyl β‐D‐galactopyranosyl‐(1→4)‐β‐D‐xylopyranoside), (II) [Zhang, Oliver & Serriani (2012). Acta Cryst. C 68 , o7–o11], is characterized by ϕ′ = −85.7 (6)° and ψ′ = −141.6 (8)°. Inter‐residue hydrogen bonding is observed between atoms O3Xyl and O5′Man in both (IA) and (IB) [O3Xyl...O5′Man internuclear distances = 2.7268 (16) and 2.6920 (17) Å, respectively], analogous to the inter‐residue hydrogen bond detected between atoms O3Xyl and O5′Gal in (II). Exocyclic hydroxymethyl group conformation in the β‐Manp residue of (IA) is gauche–gauche, whereas that in the β‐Manp residue of (IB) is gauche–trans.  相似文献   

8.
Reaction of Rhenium(VII) Oxide with 1,4-Dioxane. Re2O62-OH)2 · 3 C4H8O2— a Novel Oxide Hydroxide with Metal-(1,4-Dioxane) Bonds The reaction of Re2O7 with 1,4-dioxane in the presence of small amounts of H2O yields the compound Re2O6(OH)2 · 3(1,4-dioxane). It crystallizes in the triclinic space group P¯1 with a = 10.907(3), b = 12.875(4), c = 7.943(2) Å; α = 108.64(2), β = 103.00(2), γ = 102.29(2)°; Z = 2. The complete X-ray structure analysis (R = 2.9? ) shows the crystals to contain dimeric centrosymmetric Re2O6(OH)2-units with two bridging μ2-OH groups. The ligand spheres around Re are completed towards distorted octahedra by coordinated 1,4-dioxane molecules (one O donor per Re), the latter linking the dimeric units to endless chains. The rest of the 1,4-dioxane molecules are bonded to the OH-groups through hydrogen bridges and have no contact to Re. Mean bond distances are: Re? O(bridge) 2.065 (2.059…2.070(4)) Å, Re? O(1,4-dioxane) 2.478 (2.469 and 2.486(5)) Å, Re? O (terminal) 1.707 (1.694…1.720(5)) Å.  相似文献   

9.
2-Vinyl-1,3-dioxolane was polymerized by use of α,α′-azobisisobutyronitrile (AIBN) or by γ-ray irradiation. The polymer obtained was white amorphous powder which melted at ca. 70°C. and was soluble in chloroform, acetone, and p-dioxane. The infrared spectrum of the polymer indicated peaks at 1735 cm.?1 characteristic of the carbonyl group, and at 1200–1000 cm.?1 characteristic of the acetal group, while no absorption at 990 and 3100 cm.?1 due to the vinyl group was observed. The spectra of the polymers obtained by AIBN and by γ-ray irradiation were essentially identical. The saponified product of the polymer was white powder and its reduced viscosity was a little larger than that of the original polymer. These results indicate that the polymer has no ester unit in the main chain. The results of gas chromatographic analysis of the saponified product of the polymer, indicate the presence of a small amount of ethyl alcohol. The results of the saponification showed that the ester content in the polymer varied from 7 to 25% depending upon the polymerization temperature. These results indicate that 2-vinyl-1,3-dioxolane polymerized by AIBN or by γ-irradiation with two modes of vinyl and hydrogen migration, yielding a copolymer having the unit structures   相似文献   

10.
The asymmetric conjugate addition of malonate esters to α,β‐unsaturated N‐sulfonyl imines is catalyzed by PyBOX/La(OTf)3 complexes in the presence of 4 Å MS. The reaction gives the corresponding E enamines bearing a stereogenic center at the allylic position with good yields and enantiomeric ratios up to 97:3. This reaction provides a synthetic entry to chiral δ‐aminoesters and piperidones.  相似文献   

11.
Demetallation rates of α,β,γ,δ-tetrakis(p-sulfophenyl)porphiniron(III) in hydrochloric acid–ethanol–water, perchloric acid–ethanol–water, and sulfuric acid–alcohol–water media were determined. For a given acidity value H0 the order of the rates for the three acids was HCl > H2SO4 > HClO4. This is also the order for complex formation between acid anion and iron(III). Consequently ligands as well as protons are involved in the breaking of bonds between the metal and the porphyrin leading to the formation of the activated complex. The log k values for HCl and HClO4 media were not linearly related to the Hammett acidity function as they were for sulfuric acid–ethanol–water media. The average ΔH? and ΔS?values for the HCl media were 18.4 ± 1.4 kcal/mol and ? 19 ± 3 cal K mol, respectively, in very close agreement with those for H2SO4 media despite the difference in H 0 dependence. For H2SO4–alcohol–water media the order of the rates was butanol > propanol > ethanol with little difference between isomeric alcohols.  相似文献   

12.
The title compound has been synthesized by the reaction of α-dithionaphthoic acid with CuCl2 in pyridine or by recrystallizing Cu4(α-C10H7CSS2)4 ? 1/2CS2 in a mixture of pyridine and alcohol. The structure of the title compound is determined by a single-crystal X-ray diffraction analysis. The crystal belongs to triclinic space group with unit cell parameters: a=7.085(2)Å, b= 8.672(3)Å and c=13.598(5)Å; a=92.40(3)°, β=102.59(4)° and γ=105.67(4)°; V=780.6Å2; Z=1. The structure was refined to R=0.058 for 2390 reflections. The molecule of the title compound sits on a center of symmetry. The shorter Cu—Cu bond length (2.606Å) shows considerable interaction between copper atoms. If the Cu—Cu interaction is ignored, the neighbouring S and N atoms are coordinated to copper atom in a configuration of distorted tetrahedron.  相似文献   

13.
The η2‐thio‐indium complexes [In(η2‐thio)3] (thio = S2CNC5H10, 2 ; SNC4H4, (pyridine‐2‐thionate, pyS, 3 ) and [In(η2‐pyS)22‐acac)], 4 , (acac: acetylacetonate) are prepared by reacting the tris(η2‐acac)indium complex [In(η2‐acac)3], 1 with HS2CNC5H10, pySH, and pySH with ratios of 1:3, 1:3, and 1:2 in dichloromethane at room temperature, respectively. All of these complexes are identified by spectroscopic methods and complexes 2 and 3 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 : space group, C2/c with a = 13.5489(8) Å, b = 12.1821(7) Å, c = 16.0893(10) Å, β = 101.654(1)°, V = 2600.9(3) Å3, and Z = 4. The structure was refined to R = 0.033 and Rw = 0.086; Crystal data for 3 : space group, P21 with a = 8.8064 (6) Å, b = 11.7047 (8) Å, c = 9.4046 (7) Å, β = 114.78 (1)°, V = 880.13(11) Å3, and Z = 2. The structure was refined to R = 0.030 and Rw = 0.061. The geometry around the metal atom of the two complexes is a trigonal prismatic coordination. The piperidinyldithiocarbamate and pyridine‐2‐thionate ligands, respectively, coordinate to the indium metal center through the two sulfur atoms and one sulfur and one nitrogen atoms, respectively. The short C‐N bond length in the range of 1.322(4)–1.381(6) Å in 2 and C‐S bond length in the range of 1.715(2)–1.753(6) Å in 2 and 3 , respectively, indicate considerable partial double bond character.  相似文献   

14.
The binary thorium tritelluride, α‐ThTe3, was synthesized by solid‐state methods at 1223 K. From a single‐crystal X‐ray diffraction study the material crystallizes in the TiS3 structure type with two formula units in space group C22hP21/m of the monoclinic system in a cell with lattice constants a = 6.1730 (4) Å, b = 4.3625(3) Å, c = 10.4161(6) Å, and β = 97.756(3)° (at 100 K). The asymmetric unit of this compound comprises one Th atom and three Te atoms each with site symmetry m. Each Th atom is coordinated to eight Te atoms in a bicapped trigonal‐pyramidal arrangement. Th–Te distances range from 3.1708(4) Å to 3.2496(6) Å. The structure features a Te–Te interaction 2.7631(8) Å in length, which is typical for a Te–Te single bond. Thus α‐ThTe3 may be charge balanced and formulated as Th4+Te2–Te22–.  相似文献   

15.
Crystal structures of a series of manganese(I) complexes containing tripodal ligands were determined. For [η3-{CH3C(CH2PPh2)2(CH2SPh)-P,P′,S}Mn(CO)3]PF6 ( 1 ): a = 10.856(3) Å, b = 19.698(3) Å, c = 17.596(5) Å, β = 96.17(2)°, monoclinic, Z = 4, P21/c, R(Fo) = 0.068, Rw(Fo) = 0.055 for 3617 reflections with Io > 2σ(Io). For [η3-{CH3C(CH2PPh2)(CH2SPh)2-P,P′,S}Mn(CO)3]PF6 ( 2 ): a = 9.890(2) Å, b = 20.403(4) Å, c = 10.269(3) Å, β = 117.44(2)°, monoclinic, Z = 2, P2l, R(Fo) = 0.050, Rw(Fo) = 0.037 for 1760 reflections with Io > 2σ(Io). For [η3-{CH3C(CH2PPh2)2(CH2S)-P,P′,S}Mn(CO)3] ( 4 ): a = 8.191(7) Å, b = 10.495(3) Å, c = 19.858(6) Å, α = 99.61(2)°, β = 96.17(2)°, γ = 92.70(4)°, triclinic, Z = 2, P-I, R(Fo) = 0.048, Rw(Fo) = 0.039 for 2973 reflections with Io > 2σ(Io). There is no significant difference in the bond lengths of Mn-S bonds among three species in their crystal structures [2.325(2) Å in 1; 2.358(4) in 2; 2.380(2) in 4], but the better donating ability of thiolate in complex 4 appears on the lower frequencies of its carbonyl stretching absorptions.  相似文献   

16.
N-Sulfinylimines derived from aromatic and aliphatic aldehydes react with nitroethane and NaOH, yielding mainly two diastereoisomeric β-nitroamines as the result of a highly diastereoselective reaction and further epimerization of the carbon linked to the nitro group. The resulting β-nitroamines are used as precursors of N-sulfonyl α-amino methyl ketones and β-amino hydroxylamines.  相似文献   

17.
The treatment of a β3‐amino acid methyl ester with 2.2 equiv. of lithium diisopropylamide (LDA), followed by reaction with 5 equiv. of N‐fluorobenzenesulfonimide (NFSI) at ?78° for 2.5 h and then 2 h at 0°, gives syn‐fluorination with high diastereoisomeric excess (de). The de and yield in these reactions are somewhat influenced by both the size of the amino acid side chain and the nature of the amine protecting group. In particular, fluorination of N‐Boc‐protected β3‐homophenylalanine, β3‐homoleucine, β3‐homovaline, and β3‐homoalanine methyl esters, 5 and 9 – 11 , respectively, all proceeded with high de (>86% of the syn‐isomer). However, fluorination of N‐Boc‐protected β3‐homophenylglycine methyl ester ( 16 ) occurred with a significantly reduced de. The use of a Cbz or Bz amine‐protecting group (see 3 and 15 ) did not improve the de of fluorination. However, an N‐Ac protecting group (see 17 ) gave a reduced de of 26%. Thus, a large N‐protecting group should be employed in order to maximize selectivity for the syn‐isomer in these fluorination reactions.  相似文献   

18.
Synthesis and Crystal Structures of α‐, β‐Ba3(PS4)2 and Ba3(PSe4)2 Ba3(PS4)2 and Ba3(PSe4)2 were prepared by heating mixtures of the elements at 800 °C for 25 h. Both compounds were investigated by single crystal X‐ray methods. The thiophosphate is dimorphic and undergoes a displacive phase transition at about 75 °C. Both modifications crystallize in new structure types. In the room temperature phase (α‐Ba3(PS4)2: P21/a; a = 11.649(3), b = 6.610(1), c = 17.299(2) Å, β = 90.26(3)°; Z = 4) three crystallographically independent Ba atoms are surrounded by ten sulfur atoms forming distorted polyhedra. The arrangement of the PS4 tetrahedra, isolated from each other, is comparable with the formation of the SO42? ions of β‐K2SO4. In β‐Ba3(PS4)2 (C2/m; a = 11.597(2), b = 6.727(1), c = 8.704(2) Å; β = 90.00(3)°; Z = 2) the PS4 tetrahedra are no more tilted along [001], but oriented parallel to each other inducing less distorted tetrahedra and polyhedra around the Ba atoms, respectively. Ba3(PSe4)2 (P21/a; a = 12.282(2), b = 6.906(1), c = 18.061(4) Å; β = 90.23(3)°; Z = 4) is isotypic to α‐Ba3(PS4)2 and no phase transition could be detected up to about 550 °C.  相似文献   

19.
The copolymerization of 4-hydroxy-4′-vinylbiphenyl (HVB) with α-chloromaleic anhydride (CMAn) was investigated in THF, 1,4-dioxane, and acetonitrile. The formation of the 1:1 charge transfer complex between HVB and CMAn was confirmed spectroscopically, and the corresponding equilibrium constant (Keq) was determined as follows: Keq = 0.19, 0.11, and 0.058 mol/L in THF, 1,4-dioxane, and CH3CN, respectively. The copolymer composition is affected by the solvent, i.e., the content of HVB in the copolymer obtained in THF or 1,4-dioxane is lower than 50 mol % whereas the copolymer obtained in CH3CN has excess of HVB units. The maximum rate of copolymerization was observed at a 1:1 initial comonomer mole ratio, irrespective of the solvent polarity. Plots of Rp/[HVB] vs. [HVB] gave a straight line with a slope and an intercept for the copolymerization in THF whereas a straight line in CH3CN has no slope. On the basis of these results and 13C-NMR spectra of the copolymers, the mechanism of the predominant formation of alternating copolymers is discussed.  相似文献   

20.
The least protonated hexamolybdoplatinate(IV) polyanion, [H2α‐PtMo6O24]6?, is isolated by using Nd3+ as a counter‐cation. Two O atoms of the central PtO6 octahedron are protonated. The Mo—Mo distances are 3.244 (2), 3.295 (2) and 3.393 (1) Å, and the Pt—Mo distances are 3.251 (1), 3.332 (2) and 3.338 (1) Å. The anion has the Pt atom on an inversion centre and has close to m symmetry, with Pt—O bond lengths in the range 2.002 (8)–2.015 (8) Å and Mo—O bond lengths in the ranges 1.689 (9)–1.747 (8), 1.890 (8)–2.037 (8) and 2.109 (8)–2.384 (8) Å.  相似文献   

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