共查询到20条相似文献,搜索用时 31 毫秒
1.
《Polyhedron》2005,24(16-17):2269-2273
Two ion-pair compounds, consisting of 1-(4′-R-benzyl)pyridinium ([RBzPy]+, R = NO2 (1) and Br (2)) and [Ni(dmit)2]− (dmit2− = 2-thioxo-1,3-dithion-4,5-dithiolato), have been synthesized and structurally characterized. The anions of [Ni(dmit)2]− stack into dimers, which further construct into two-leg ladder through terminal S⋯S interactions in 1, lateral S⋯S interactions in 2. The weak H-bonding interactions of C–H⋯S were observed in 2, while only weak van de Waals interactions between anion and cations in 1. The magnetic susceptibilities measured in 2–300 K indicate AFM exchange interaction domination both two compounds. A peculiar magnetic transition at ∼100 K was observed in 1. An AFM ordering below ∼11 K was found in 2, and the best fit to magnetic susceptibility above 45 K in this compound, using a dimer model with s = 1/2, give rise to Δ/kB = 36.1 K, zJ = −0.91 K, C = 3.2 × 10−3 emu K mol−1 and χ0 = −4.0 × 10−6 emu mol−1 with g of 2.0 fixed. 相似文献
2.
《Tetrahedron: Asymmetry》2006,17(4):566-573
A highly enantioselective cyano-phosphorylation of aldehydes catalyzed by a YLi3tris(binaphthoxide) complex YLB 1 is described. The slow addition of diethyl cyanophosphonate 4 to aldehydes 5 in the presence of YLB 1 (10 mol %), H2O (30 mol %), tris(2,6-dimethoxyphenyl)phosphine oxide 3a (10 mol %), and BuLi (10 mol %) afforded cyanohydrin O-phosphates 6 in up to 98% yield and 97% ee. Mechanistic studies revealed that the addition of cyanide to aldehydes is irreversible and determines the enantioselectivity. The reaction mechanism is also discussed in detail. 相似文献
3.
Reaction of 2,2-difluoro-1-tributylstannylethenyl p-toluenesulfonate (1) with bis(tributyltin) in the presence of 5 mol % Pd(PPh3)4 and 30 equiv LiBr in THF at reflux temperature for 7 h afforded (2,2-difluoroethenylidene)bis(tributylstannane) (2) in a 70% yield. Coupling reaction of 2 with aryl iodides in the presence of 5 mol % Pd(PPh3)4 and 5 mol % CuI in DMF at 80 °C for 3–4 h provided the coupled products 3 in 59–85% yields. 相似文献
4.
《Arabian Journal of Chemistry》2014,7(4):461-468
A series of new 5α-cholestano [5,6-b] benzothiazines (4–6) has been synthesized by the reaction of 5α-cholestan-6-one (1–3) with 2-aminothiophenol in the presence of iodine. The structures of newly synthesized compounds have been established on the basis of spectral and analytical data. Compounds (1–6) were screened for in vitro anticancer activity against the human cancer cell lines; SW480 (colon adenocarcinoma cells), A549 (lung carcinoma cells), HepG2 (hepatic carcinoma cells) and HeLa (cervical cancer cells) using MTT assay during which the products (4–6) showed marked increase in anticancer activity and in particular, compound 6 showed IC50 = 13.73 μmol L−1 against HeLa cells, being more effective than Doxorubicin against the same cells. Compounds 4 and 6 also showed minimum IC50 of 15.83 μmol L−1 and 16.89 μmol L−1 against HepG2 and A549 cells, respectively. Compounds (1–6) were also tested for in vitro antimicrobial activity against different bacterial as well as fungal strains during which newly synthesized compounds (4–6) were found more potent than starting compounds (1–3). Compound 4 was found to be more potent than the reference drug, Chloramphenicol, in the case of Escherichia coli while compound 5 was found almost equally potential antifungal agent against P. marneffei in comparison with the reference drug, Nystatin. 相似文献
5.
Three new CO2-philic bis(2-ethoxyethyl) ethanedioate derivatives, bis(2-(2-methoxyethoxy)ethyl) ethanedioate (compound 1), bis(2-(2-ethoxyethoxy)ethyl) ethanedioate (compound 2), and bis(2-(2-butoxyethoxy)ethyl) ethanedioate (compound 3), were designed and synthesized and their solubilities in supercritical carbon dioxide (scCO2) were then measured at different temperatures (313, 323, 333) K over the pressure range (8.9 to 13.9) MPa. The measured solubility data were correlated with five different theoretical semi-empirical models (Chrastil, kJ, SS, MST, JCF) and satisfactory agreements were obtained. The JCF model provided the best fit and the lowest average absolute relative deviation (AARD) varied from (3.58 to 6.80)%. Furthermore, the partial molar volumes of three compounds in the supercritical phase were also calculated according to the Kumar and Johnston theory, and the values were between −(19105 and 3510) cm3 · mol−1. 相似文献
6.
Chang Xu Yongxin Li Lai Yoong Goh Sumod A. Pullarkat 《Journal of organometallic chemistry》2012,696(26):4207-4214
The reaction of [Cp1IrCl2]2 (Cp* = η5 ? C5Me5) with the tridentate 3-thiapentane-1,5-dithiolate ligand, S(CH2CH2S?)2 (tpdt), led to the formation of [Cp1Ir(η3 ? tpdt)] (1) in 81% isolated yield. Subsequent reactions of 1 with [Cp1IrCl2]2 in 2:1 and 1:1 molar equiv ratios resulted in the formation of [Cp1Ir(μ ? η2:η3 ? tpdt)Cp1IrCl][PF6] (2) and [Cp1Irμ ? η2:η3 ? tpdt)Cp1IrCl][Cp1IrCl3] (3) in 86 and 79% yields, respectively, based on 1, whereas the reactions of 1 with [(COD)IrCl]2 (COD = 1,5-cyclooctadiene) in 2:1 and 1:1 molar equiv ratios resulted in the formation of the homo-bimetallic derivatives Cp1Ir(μ ? η1:η3 ? tpdt)(COD)IrCl (4) (92% yield) and [Cp1Ir(μ ? η2:η3 ? tpdt)(COD)Ir] [(COD)IrCl2] (5) (82% yield). Reactions between 1 and [(COD)RhCl]2, yielded the hetero-bimetallic derivatives Cp1Ir(μ ? η1:η3 ? tpdt)(COD)RhCl (6) and [Cp1Ir(μ ? η2:η3 ? tpdt)(COD)Rh][(COD)RhCl2] (7), in 92 and 93% yields, respectively. The reaction of 1 with methyl iodide gave mono-methylated derivative [Cp1Ir(η3-C4H8S3Me)]I (8) (93% yield). All these compounds have been comprehensively characterized. 相似文献
7.
Valeriu Mereacre Yanhua Lan Wolfgang Wernsdorfer Christopher E. Anson Annie K. Powell 《Comptes Rendus Chimie》2012,15(7):639-646
A series of four isostructural dodecanuclear complexes [MnIII9MnII2LnIII(O)8(OH)(piv)16(NO3)(CH3CN)]·xCH3CN·yC7H16 (piv = pivalate; x = ½, y = ¾, Ln = Tb (1); x = 2, y = ½, Ln = Dy (2), Ho (3), and Y (4)) has been prepared for which the structural motif described as ‘a lanthanide ion nested in a large manganese shell’ is observed. All compounds show out-of-phase signals in their ac susceptibilities, and their single-molecule magnet behaviour was confirmed by single-crystal micro-SQUID studies of 1-3 which show hysteresis loops of molecular origin at T < 1.0 K. The SMM behaviour observed in compounds 1-3 is more pronounced than that for 4, which contains the diamagnetic YIII ion. This is principally the result of ferromagnetic coupling between the paramagnetic anisotropic LnIII ions (TbIII, DyIII and HoIII) and the manganese shell, which enhances the total spin ground state of the complexes. 相似文献
8.
《Journal of organometallic chemistry》2011,696(26):4207-4214
The reaction of [Cp1IrCl2]2 (Cp* = η5 − C5Me5) with the tridentate 3-thiapentane-1,5-dithiolate ligand, S(CH2CH2S−)2 (tpdt), led to the formation of [Cp1Ir(η3 − tpdt)] (1) in 81% isolated yield. Subsequent reactions of 1 with [Cp1IrCl2]2 in 2:1 and 1:1 molar equiv ratios resulted in the formation of [Cp1Ir(μ − η2:η3 − tpdt)Cp1IrCl][PF6] (2) and [Cp1Irμ − η2:η3 − tpdt)Cp1IrCl][Cp1IrCl3] (3) in 86 and 79% yields, respectively, based on 1, whereas the reactions of 1 with [(COD)IrCl]2 (COD = 1,5-cyclooctadiene) in 2:1 and 1:1 molar equiv ratios resulted in the formation of the homo-bimetallic derivatives Cp1Ir(μ − η1:η3 − tpdt)(COD)IrCl (4) (92% yield) and [Cp1Ir(μ − η2:η3 − tpdt)(COD)Ir] [(COD)IrCl2] (5) (82% yield). Reactions between 1 and [(COD)RhCl]2, yielded the hetero-bimetallic derivatives Cp1Ir(μ − η1:η3 − tpdt)(COD)RhCl (6) and [Cp1Ir(μ − η2:η3 − tpdt)(COD)Rh][(COD)RhCl2] (7), in 92 and 93% yields, respectively. The reaction of 1 with methyl iodide gave mono-methylated derivative [Cp1Ir(η3-C4H8S3Me)]I (8) (93% yield). All these compounds have been comprehensively characterized. 相似文献
9.
Cécile Verrier Sylvain Oudeyer Isabelle Dez Vincent Levacher 《Tetrahedron letters》2012,53(15):1958-1960
Several metal (Na+, Ca2+) or ammonium (n-Bu4N+) derivatives of alginic acid, an abundant bio-polymer obtained from the cell walls of brown algae, were synthesized. Their potential to act as organocatalysts to catalyze the 1,2-addition of various silyl derivatives to carbonyl compounds was evaluated for the first time. Ammonium alginate 1h is able to promote the reaction in modest to good isolated yields (up to 98%) affording access to a large range of substrates (β-cyano alcohols or ester, β-substituted methylacrylate or acrylonitrile, and cyanohydrin) by using only 5 mol % of catalyst. 相似文献
10.
Blanka Kašná Roman Jambor Markus Schürman Klaus Jurkschat 《Journal of organometallic chemistry》2008,693(21-22):3446-3450
The syntheses are reported of the novel heteroleptic organostannylenes [2,6-(ROCH2)2C6H3]SnCl (1, R = Me; 2, R = t-Bu) and of their tungstenpentacarbonyl complexes [2,6-(ROCH2)2C6H3](X)SnW(CO)5 (3, X = Cl, R = Me; 4, X = Cl, R = t-Bu; 5, X = H, R = Me). The compounds were characterized by means of elemental analyses, 1H, 13C, 119Sn NMR spectroscopies, electrospray mass spectrometry and in case of 3 and 4 also by single crystal X-ray diffraction analysis. For the two latter compounds the substituents bound at the ether oxygen atom control the strength of intramolecular O → Sn coordination. Thus, the O–Sn distances amount to 2.391(5)/2.389(5) (3) and 2.464(3)/2.513(3) Å (4). 相似文献
11.
《Tetrahedron: Asymmetry》2007,18(13):1540-1547
Syntheses of trans-1,2-di-tert-butylpyrazolidine 1, d,l- and semi-meso-1,2-diisopropyl-3,5-dimethylpyrazolidines, 2a and 2b, respectively, have been developed. Activation parameters of the nitrogen inversion in 1 (ΔG≠ = 123 kJ mol−1 at 110 °C, ΔH≠ = 114 kJ mol−1, ΔS≠ = −15 J K−1 mol−1) have been determined. The steric veto of the nitrogen inversion in 2a has been confirmed. Chemical transformations of 1 have been studied, and the crystal structures of 2a·picrate and 2b·HCl determined. 相似文献
12.
Two new hybrid materials, (C4H14N2)[MII(H2O)6](SO4)2·4H2O (MII: Co (I), Ni (II)), have been synthesised by slow evaporation method at room temperature and crystallographically characterized. They crystallise isotypically in the monoclinic system, space group P21/n, with the following unit-cell parameters a = 9.2285(3), b = 11.3333(4), c = 10.6693(4) Å, β = 109.004(2)°, Z = 2 and V = 1055.07(6) Å3 for I and a = 9.2127(2), b = 11.3182(2), c = 10.6434(2) Å, β = 109.094(1)°, Z = 2 and V = 1048.74(4) Å3 for II. The structure of the two supramolecular compounds consists of metallic cation octahedrally coordinated to six water molecules, sulfate anions, 1,4-butanediammonium cation and water molecules linked together via two types of hydrogen bonds, O–H?O and N–H?O. The two compounds are not stable at room temperature and their partial dehydration depends on the humidity of the environment. The thermal decomposition of precursors, studied by thermogravimetric analysis (TG) and temperature-dependent X-ray diffraction (TDXD), shows successive intermediate hydrates and crystalline anhydrous compounds upon dehydration. 相似文献
13.
《Polyhedron》2007,26(9-11):1876-1880
The crystalline one-dimensional compounds, [M2(bza)4(pyz)]n (bza = benzoate; pyz = pyrazine; M = CuII (1)) and [M2(bza)4(2-mpyz)]n (2-mpyz = 2-methylpyrazine; M = RhII (2), CuII (3)), demonstrate gas absorbency of NO. The amounts of adsorbed NO gas are 0.61 for 1, 0.30 for 2, and 0.23 for 3 per M2 unit at 195 K (800 Torr). The crystals of 1 adsorbed more NO molecules than did those of 2 and 3. The magnetic susceptibilities of the NO-inclusion crystals indicate that included NO molecules interact antiferromagnetically with neighboring guests without dimerization to N2O2. Magnetic behaviors indicated NO aggregation in the narrow 1D channels of 1–3 under unsaturated adsorption conditions. 相似文献
14.
《Journal of organometallic chemistry》2006,691(1-2):35-44
The reaction of organoaluminum compounds containing O,C,O or N,C,N chelating (so called pincer) ligands [2,6-(YCH2)2C6H3]AliBu2 (Y = MeO 1, tBuO 2, Me2N 3) with R3SnOH (R = Ph or Me) gives tetraorganotin complexes [2,6-(YCH2)2C6H3]SnR3 (Y = MeO, R = Ph 4, Y = MeO, R = Me 5; Y = tBuO, R = Ph 6, Y = tBuO, R = Me 7; Y = Me2N, R = Ph 8, Y = Me2N, R = Me 9) as the result of migration of O,C,O or N,C,N pincer ligands from aluminum to tin atom. Reaction of 1 and 2 with (nBu3Sn)2O proceeded in similar fashion resulting in 10 and 11 ([2,6-(YCH2)2C6H3]SnnBu3, Y = MeO 10; Y = tBuO 11) in mixture with nBu3SniBu. The reaction 1 and 3 with 2 equiv. of Ph3SiOH followed another reaction path and ([2,6-(YCH2)2C6H3]Al(OSiPh3)2, Y = MeO 12, Me2N 13) were observed as the products of alkane elimination. The organotin derivatives 4–11 were characterized by the help of elemental analysis, ESI-MS technique, 1H, 13C, 119Sn NMR spectroscopy and in the case 6 and 8 by single crystal X-ray diffraction (XRD). Compounds 12 and 13 were identified using elemental analysis,1H, 13C, 29Si NMR and IR spectroscopy. 相似文献
15.
《Polyhedron》2005,24(3):397-406
Four 4,4′-bipyridine α,ω-dicarboxylate coordination polymers Cu(bpy)(C5H6O4) (1), Zn(bpy)(C5H6O4) (2), Zn(bpy)(C6H8O4) (3) and Mn(bpy)(C8H12O4) · H2O (4) have been synthesized and structurally characterized by single crystal X-ray diffraction methods (bpy = 4,4-bipyridine, (C5H6O4)2− = glutarate anion, (C6H8O4)2− = adipate anion, (C8H12O4)2− = suberate anion). Their crystal structures are featured by dimeric metal units, which are co-bridged by 4,4′-bipyridine ligands and dicarboxylate anions such as glutarate, adipate and suberate anions to generate 2D layers with a (4,4) topology in 1, 2 and 4 as well as to form 3D frameworks in 3. Two 3D frameworks in 3 interpenetrate with each other to form a topology identical to the well-known Nb6F15 cluster compound. Over 5–300 K, the paramagnetic behavior of 4 follows the Curie–Weiss law χm(T − Θ) = 4.265(5) cm3 mol−1 with the Weiss constant Θ = −6.3(2) K. Furthermore, the thermal behavior of 3 and 4 is also discussed. 相似文献
16.
《Polyhedron》2007,26(9-11):2121-2125
The hybrid organo-inorganic compounds [Cu4(bipy)4V4O11(PO4)2]nH2O (n ∼ 5) (1), [Cu2(phen)2(PO4)(H2PO4)2(VO2) · 2H2O] (2) and [Cu2(phen)2(O3PCH2PO3)(V2O5) (H2O)]H2O (3) which present different bridging forms of the phosphate/phosphonate group, show different bulk magnetic properties. We herein analyze the magnetic behaviour of these compounds in terms of their structural parameters. We also report a theoretical study for compound (1) assuming four different magnetic exchange pathways between the copper centres present in the tetranuclear unit. For compound (1) the following J values were obtained J1 = +3.29; J2 = −0.63; J3 = −2.23; J4 = −46.14 cm−1. Compound (2) presents a Curie–Weiss behaviour in the whole range of temperature (3–300 K), and compound (3) shows a maximum for the magnetic susceptibility at 64 K, typical for antiferromagnetic interactions. These data where fitted using a model previously reported in the literature, assuming two different magnetic exchange pathways between the four copper(II) centres, with J1 = −30.0 and J2 = −8.5 cm−1. 相似文献
17.
Using the polyfunctional ligand 2-phosphonethanesulfonic acid (H3L) a high-throughput (HT) study was started for the systematic investigation of the system SrCl2/H3L/NaOH/H2O. The HT experiment comprising 48 individual reactions were performed to systematically investigate the influence of pH of the starting mixture as well as the molar ratio Sr2+:H3L. Two new compounds SrH(O3P–C2H4–SO3) (1) and Sr3(O3P–C2H4–SO3)2(H2O)2 (2) were obtained and structurally characterized by single-crystal X-ray diffraction. The reaction products synthesized under hydrothermal conditions always contain traces of SrSO4, which are due to the decomposition of small amounts of the ligand. While compound 2 could only be obtained under hydrothermal conditions, the synthesis of 1 could be accomplished under milder reaction conditions and a reaction scale-up could be performed. Compound 1 crystallizes in a monoclinic system with space group C2/c (no. 15), a = 534.73(11) pm, b = 1648.7(3) pm, c = 825.43(17) pm, β = 105.34(3)°, V = 701.8(2)–106 pm3, Z = 4, R1 = 0.0268, and wR2 = 0.0642 for I > 2σ(I). Compound 2 crystallizes in a triclinic system with space group P-1 (no. 2), a = 700.97(14) pm, b = 1008.5(2) pm, c = 1274.8(3) pm, α = 97.63(3)°, β = 92.03(3)°, γ = 92.03(3)°, V = 843.7(3)–106 pm3, Z = 2, R1 = 0.0360, and wR2 = 0.0896 for I > 2σ(I). In the structure of compound 1 the phosphorous and sulfur atoms cannot be distinguished due to identical crystallographic positions. Thus, an averaged structure was obtained which is built up by edge-sharing SrO8 polyhedra that form infinite M–O–M chains. Compound 2 contains corner-, edge-, and face-sharing SrO8 polyhedra which form inorganic M–O–M layers. These M–O–M chains (1) and layers (2) are connected to a three-dimensional network by the –CH2CH2– group of the ligand, respectively. Additional characterization by thermogravimetric analysis and IR-spectroscopy for compound 1 is also presented. 相似文献
18.
Shuangliu Zhou Da-Wei Chuang Shih-Ju Chang Han-Mou Gau 《Tetrahedron: Asymmetry》2009,20(12):1407-1412
A series of phenylaluminum reagents AlPhxEt3?x(L) (x = 1–3) containing adduct ligand L [Et2O, THF, OPPh3, or 4-dimethylaminopyridine (DMAP)] were synthesized and characterized. NMR studies showed that AlPhxEt3?x(L) (x = 1 or 2) exists as an equilibrium mixture of 3–4 species in solution. Solid-state structures of the phenylaluminum reagents reveal a distorted tetrahedral geometry. Asymmetric additions of phenylaluminum to 2-chlorobenzaldehyde were examined employing a titanium(IV) complex [TiL1(OPri)2]2 10 (H2L1 = (1R,2S)-2-(p-tolylsulfonylamino)-1,3-diphenyl-1-propanol) as a catalyst precursor. It was found that the adduct ligand L had a strong influence on the reactivity and the enantioselectivity in asymmetric phenyl additions to aldehydes. The phenylaluminum reagents with OPPh3 or DMAP were unreactive toward aldehydes, and AlPh3(THF) was found to be superior to AlPh3(OEt2) or AlPhEt2(THF). Asymmetric aryl additions of AlAr3(THF) to aldehydes employing a loading of 5 mol % titanium(IV) complex 10 with a strategy of a slow addition of the aldehydes over 20 min were conducted, and the reactions produced optically active secondary alcohols in high yields with excellent enantioselectivities of up to 94% ee. 相似文献
19.
Picolyl, pyridine, and methyl functionalized N-heterocyclic carbene iridium complexes [Cp1Ir(C^N)Cl]Cl (4, C^N = 3-Methyl-1-picolyimidazol-2-ylidene), [Cp1Ir(C^N)Cl][Cp1IrCl3] (5), [Cp1Ir(C-N)Cl]Cl (6, C-N = 3-Methyl-1-pyridylimidazol-2-ylidene) and [Cp1Ir(L)Cl2] (7, L = 1,3-dimethylimidazol-2-ylidene) have been synthesized by transmetallation from Ag(I) carbene species, and characterized by 1H NMR, 13C NMR spectra and elemental analyses. The molecular structures of 5–7 have been confirmed by X-ray single-crystal analyses. The iridium carbene complexes 4 and 6 show moderate catalytic activities (3.03 × 105 g PNB (mol Ir)?1 h?1 and 1.70 × 106 g PNB (mol Ir)?1 h?1) for the addition polymerization of norbornene in the presence of methylaluminoxane (MAO) as co-catalyst. The produced polynorbornene have been characterized by IR, 1H NMR and 13C NMR spectra, showing it follows the vinyl-addition-type of polymerization. 相似文献
20.
《Polyhedron》2005,24(16-17):2242-2249
Two heterobimetallic coordination polymers, [Cu(2,4-pydc)2Mn(H2O)4]x (1) and [Cu(2,5-pydc)2Mn(H2O)2]x · 4xH2O (2), have been synthesized and structurally characterized by single crystal X-ray diffraction. Both compounds have extended 2-D sheet structures. In 1 the copper centers are linked in chains by double ligand bridges and these chains are cross-linked through the manganese coordination spheres and O–C–O bridges to form polymeric sheets. In 2 separate O–C–O bridged Cu and Mn chains are connected in an alternating array by additional ligand bridging to generate the overall 2-D structure. Analysis of magnetic data of 1 reveals that ferromagnetic exchange between the O–C–O bridged copper and manganese centers dominates the magnetic properties of this system. The magnetic data for 2 fit well to a model incorporating antiferromagnetic exchange in independent S = 1/2 and S = 5/2 linear chains with J(Cu) = −0.073 cm−1 and J(Mn) = −0.32 cm−1. Unlike the situation in 1, there is no evidence for heterometallic exchange. In both 1 and 2 the significant exchange occurs via O–C–O bridges. To study the effect of thermal dehydration on the magnetic properties of these systems, the compounds Cu(2,4-pydc)2Mn · H2O (1d) and Cu(2,5-pydc)2Mn · H2O (2d) were synthesized and studied. 相似文献