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1.
Fluorescence properties of five 4-acyl pyrazolone based hydrazides (H2SBn) and their Fe (III) heterochelates of the type [Fe(SBn)(L)(H2O)]·mH2O [H2SBn = nicotinic acid [1-(3-methyl-5-oxo-1-phenyl-4,5-di hydro-1H-pyrazol-4yl)-acylidene]-hydrazide; where acyl = –CH3, m = 4 (H2SB1); –C6H5, m = 2 (H2SB2); –CH2–CH3, m = 3 (H2SB3); –CH2–CH2–CH3, m = 1.5 (H2SB4); –CH2–C6H5, m = 1.5 (H2SB5) and HL = 1-cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid] were studied at room temperature. The fluorescence spectra of heterochelates show red shift, which may be due to the chelation by the ligands to the metal ion. It enhances ligand ability to accept electrons and decreases the electron transition energy. The kinetic parameters such as order of reaction (n), energy of activation (Ea), entropy (S*), pre-exponential factor (A), enthalpy (H*) and Gibbs free energy (G*) have been reported.  相似文献   

2.
(R)-(+)-Cibenzoline (95% ee) was synthesized in two steps from (+)-2,2-diphenylcyclopropylmethanol 3a (98% ee), which was oxidized with IBX in DMSO, followed by treatment with ethylenediamine in the presence of I2 and K2CO3 in tBuOH. Compound (R)-(+)-3a (98% ee) was prepared by cyclopropanation of 3,3-diphenyl-2-propen-1-ol 1 with Et2Zn and CH2I2 in the presence of a catalytic amount of (S)-2-(methanesulfonyl)amino-1-(p-toluenesulfonyl)amino-3-phenylpropane 2, followed by esterification with 3,5-dinitorobenzoyl chloride, recrystallization, and hydrolysis.  相似文献   

3.
《Tetrahedron: Asymmetry》2007,18(23):2727-2737
Four 3,10-pinanediol derivatives 1ad, prepared in 50–72% global yields from (1R)-(−)-myrtenal 2, were treated with (RO)2CHCOR3 (R3 = CH3, Ph) to afford 2-acyl-1,3-dioxanes 3af. The latter were submitted to nucleophilic additions using several Grignard reagents to mainly afford carbinols generated by re diastereofacial attack (85–99% yield, ⩾88:12 dr). The lowest diastereoselectivity was observed when PhLi or hydrides were used as nucleophiles. Only an equatorial substituent at C-3 modifies the diastereoselectivity of the nucleophilic additions.  相似文献   

4.
A chiral bidentate phosphoramidite (5a) was synthesized from Shibasaki’s linked-(R)-BINOL and P(NMe2)3 as a new ligand for rhodium(I)-catalyzed asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated carbonyl compounds. The effects of 5a and Feringa’s monodentate phosphoramidite (4, R1, R2 = Et) on the yields and enantioselectivities were fully investigated. The reaction was significantly accelerated in the presence of a base such as KOH and Et3N, allowing the reaction to be completed at the lower temperatures than 50 °C. The addition to cyclic enones such as 2-cyclopentenone, 2-cyclohexenone and 2-cycloheptenone at 50 °C in the presence of an [Rh(coe)2Cl]2-4 (R1, R2 = Et) complex resulted in enantioselectivities up to 98%, though it was less effective for acyclic enones (0–70% ee). On the other hand, a complex between [Rh(nbd)2]BF4 and 5a completed the addition to cyclic enones within 2 h at room temperature in the presence of Et3N with 86–99% yields and 96–99.8% ee. This catalyst was also effective for acyclic enones, resulting in 62–98% yields and 66–94% ee. The 1,4-additions of arylboronic acids to unsaturated lactones and acyclic esters with rhodium(I)-phosphoramidites complexes were also investigated.  相似文献   

5.
A novel zinc diphosphonate, Zn[HO3PCH2(C6H4)CH2PO3H] (1) was synthesized from tetraethyl para-xylylenediphosphonate, Et2O3PCH2C6H4CH2PO3Et2, and Zn (AcO)2·2H2O under solvothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction, which reveals that the structure crystallizes in the monoclinic space group C2/c (No. 15), with a = 22.4844(19) Å, b = 6.4361(5) Å, c = 8.1194(7) Å, β = 102.595(2)°, V = 1146.70(16) Å3, T = 298(2) K, Z = 8. The novel three-dimensional (3D) construction is simply built up from linear inorganic chains of corner-sharing four-rings of tetrahedral [ZnO4] and [PO3C] which connected adjacent chains by the organophosphorus ligand para-xylylenediphosphonate. The framework has 10 Å × 4 Å (containing the van der Waals radii of atoms) channels running along the b-axis.  相似文献   

6.
《Comptes Rendus Chimie》2015,18(8):816-822
The treatment of [PdL3(NH3)]OTf (L3 = (PEt3)2(Ph) (1), (2,6-(Cy2PCH2)2C6H3) (3)) with NaNH2 in THF afforded dimeric and monomeric parent-amido palladium(II) complexes with bridging and terminal NH2, respectively, anti-[Pd(PEt3)(Ph)(μ-NH2)]2 (2) and Pd(2,6-(Cy2PCH2)2C6H3)(NH2) (4). The dimeric complex 2 crystallizes in the space group P21/n with a = 13.228(2) Å, b = 18.132(2) Å, c = 24.745(2) Å, β = 101.41(1)°, and Z = 4. It has been found that there are two crystallographically independent molecules with Pd(1)–Pd(2) and Pd(3)–Pd(4) distances of 2.9594 (10) and 2.9401(9) Å, respectively. The monomeric amido complex 4 protonates from trace amounts of water to give the cationic ammine species [Pd(2,6-(Cy2PCH2)2C6H3)(NH3)]+. Complex 4 reacts with diphenyliodonium triflate ([Ph2I]OTf) to give aniline complex [Pd(2,6-(Cy2PCH2)2C6H3)(NH2Ph)]OTf (5). Reaction of 4 with dialkyl acetylenedicarboxylate (DMAD, DEAD) yields diastereospecific palladium(II) vinyl derivative (Z)–(Pd(Cy2PCH2)2C6H3)(CR = CR(NH2)) (R = CO2Me (6a), CO2Et (6b)). Reacting complexes 6a and 6b with p-nitrophenol produces (Pd(Cy2PCH2)2C6H3)(OC6H4p-NO2) (8) and cis-CHR = CR(NH2), exclusively.  相似文献   

7.
Reaction of Mo(N-2,6-i-Pr2-C6H3)(CHCMe2C6H5)(OSO2CF3)(DME) (DME = 1,2-dimethoxyethane) with 2 equiv. of CF3COOK yields μ-(CF3COO)2-[Mo(N-2,6-i-Pr2-C6H3)(CHCMe2Ph)(OOCCF3)(Et2O)]2 (1). Compound 1 crystallizes in the orthorhombic space group Pna21 with a = 17.2485(3), b = 17.0336(3), c = 25.4031(5) Å, α = β = γ = 90°, V = 7463.5(2) Å3, Z = 4. In contrast to alkoxide based Schrock type initiators, 1 is virtually inactive in numerous metathesis reactions including ring-closing metathesis (RCM) and homo metathesis reactions, the cyclopolymerization of 1,6-heptadiynes, and even ring-opening metathesis polymerization (ROMP) of norborn-2-ene. However, addition of quinuclidine results in the in situ formation of 1a (Mo(N-2,6-i-Pr2-C6H3)(CHCMe2C6H5)(OOCCF3)2(quinuclidine) which displays moderate activity in ROMP, cyclopolymerization of 1,6-heptadiynes and RCM. Theoretical investigations carried out on the B3LYP/LACVP1 level provide substantial explanation for these findings.  相似文献   

8.
Oxidative demetalation of Fischer ferrocenyl ethoxy carbene complexes (1ac, M = Cr, Mo, W) and new Fischer ferrocenyl R-amino carbene complexes [25 (ac), 1115 (ac), and 2122 (ac); M = Cr, Mo, W; R = H, CH3, C2H5, C3H7, (CH2)2OH, (CH2)3OH, (CH2)2(OMe)2, (CH2)3N(Me)2, CH2CHCH2, (CH2)2OSi(CH3)3, (CH2)3OSi(CH3)3] with elemental sulfur–NaBH4 were carried out under mild conditions, obtaining O-ethyl ferrocenecarbothioate (6) and novel ferrocenyl thioamides (710 and 1620) in excellent yields.  相似文献   

9.
Reaction of [Ag(CH3impy)2]PF6, 1, with Au(tht)Cl produces the monometallic Au(I)-species [Au(CH3impy)2]PF6, 2. Treatment of 2 with excess AgBF4 in acetonitrile, benzonitrile or benzylnitrile produces the polymeric species {[AuAg(CH3impy)2(L)](BF4)2}n, (L = CH3CN,3; L = C6H5CN, 4; L = C6H5CH2CN, 5) where the Au(I) centers remain bound to two carbene moieties while the Ag(I) centers are coordinated to two alternating pyridyl groups and a solvent molecule (L). Reaction of 2 with AgNO3 in acetonitrile produces the zig-zag mixed-metal polymer {[AuAg(CH3impy)2(NO3)]NO3}n, 6, that contains a coordinated nitrate ion in place of the coordinated solvent species. All of these polymeric materials are dynamic in solution and dissociate into their respective monometallic components. Compounds 26 are intensely luminescent in the solid-state and in frozen solution. All of these complexes were characterized by 1H, 13C NMR, electronic absorption and emission spectroscopy and elemental analysis.  相似文献   

10.
Hypercoordinated diorganotin(IV) dichloride, [2-(Et2NCH2)C6H4]2SnCl2 (1), was prepared by reacting [2-(Et2NCH2)C6H4]Li with SnCl4. Halide-exchange reactions between 1 and the appropriate potassium halides gave [2-(Et2NCH2)C6H4]2SnX2 [X = F (2), Br (3), I (4)]. Reaction of 1 with excess of Na2S gave the cyclo-[{2-(Et2NCH2)C6H4}2SnS]2 (5). The solution behavior of the title compounds in solution was investigated by multinuclear (1H, 13C, 19F and 119Sn) NMR spectroscopy, including variable temperature studies. Single-crystal X-ray diffraction analysis revealed for all compounds intramolecular N  Sn coordination thus resulting in distorted octahedral (C,N)2SnX2 configurations. Planar chirality is observed as result of the non-planarity of the SnC3N rings; all compounds, however, crystallizing as racemates. The isomers are linked by extensive hydrogen bonds to give different supramolecular architectures in the crystals of compounds 1, 3 and 4.  相似文献   

11.
Alkyl and arylplatinum complexes with 1,5-cyclooctadiene ligand, [PtR2(cod)] (R = Me, Ph, C6H4-p-CF3, C6F5), react with secondary phosphines, PHR′2 (R′ = i-Bu, t-Bu, Ph), to afford the mononuclear platinum complexes, cis-[PtR2(PHR′2)2] (1a: R = Me, R′ = i-Bu; 1b: R = Me, R′ = t-Bu; 1c: R = Me, R′ = Ph; 2a: R = Ph, R′ = i-Bu; 2b: R = Ph, R′ = t-Bu; 2c: R = R′ = Ph; 3a: R = C6H4-p-CF3, R′ = i-Bu; 3b: R = C6H4-p-CF3, R′ = t-Bu; 3c: R = C6H4-p-CF3, R′ = Ph; 4a: R = C6F5, R′ = i-Bu; 4c: R = C6F5, R′ = Ph) in 81–98% yields. Molecular structures of the complexes except for 1a, 1c and 2a were determined by X-ray crystallography. Complex 1b has a square-planar structure with Pt–C(methyl) bonds of 2.083(8) and 2.109(8) Å, while the Pt–C(aryl) bonds of 2bc, 3ac, 4a and 4c (2.055(1)–2.073(8) Å) are shorter than them. Thermal decomposition of 1b, 2ac, and 3ac releases methane, biphenyl or 4,4′-bis(trifluoromethyl)biphenyl as the organic products, which are characterized by NMR spectroscopy. The solid product of the thermal reactions of 2b and 2c were characterized as the metallopolymers formulated as [Pt(PR′2)2]n (5b: R′ = tBu; 5c: R′ = Ph), based on the solid-state NMR and elemental analyses.  相似文献   

12.
N-Thioamide thiosemicarbazone derived of 2-chloro-4-hydroxy-benzaldehyde (R = H, HL1; R = Me, HL2 and R = Ph, HL3) have been prepared and their reaction with fac-[ReX(CO)3(CH3CN)2] (X = Br, Cl) in chloroform gave the adducts [ReX(CO)3(HL)] (1a X = Cl, R = H; 1a′ X = Br, R = H; 1b X = Cl, R = CH3; 1b′ X = Br, R = CH3; 1c X = Cl, R = Ph; 1c′ X = Br, R = Ph) in good yield. Complexes 1a′ and 1b’ were also obtained by the reaction of HL1 and HL3 with [ReBr(CO)5] in toluene.All the compounds have been characterized by elemental analysis, mass spectrometry (FAB), IR and 1H NMR spectroscopic methods. Moreover, the structures of HL2, HL3 and 1a·H2O were also established by X-ray diffraction. In 1a, the rhenium atom is coordinated by the sulphur and the azomethine nitrogen atoms, forming a five-membered chelate ring, as well as three carbonyl carbon and chloride atoms. The resulting coordination polyhedron can be described as a distorted octahedron.The study of the crystals obtained by slow evaporation of methanol and DMSO solutions of the adducts 1a′ and 1b, respectively, showed the formation of dimer structures based on rhenium(I) thiosemicarbazonates [Re2(L1)2(CO)6]·3H2O (2a)·3H2O and [Re2(L2)2(CO)6]·(CH3)2SO (2b)·2(CH3)2SO. Amounts of these thiosemicarbazonate complexes [Re2(L)2(CO)6] (2) were obtained by reaction of the corresponding free ligands with [ReCl(CO)5] in dry toluene.In 2a·3H2O and 2b·2(CH3)2SO the dimer structures are established by Re–S–Re bridges, where S is the thiolate sulphur from a N,S-bidentate thiosemicarbazonate ligand. In both structures the rhenium coordination sphere is similar; the dimers are in the same diamond Re2S2 face.  相似文献   

13.
The heterometallic cluster complexes {(p-Cymene)Ru[S2C2(B10H10)]}Mo(CO)2{(CO)3Ru[S2C2(B10H10)]} (2) and {(p-Cymene)Ru[Se2C2(B10H10)]}2Mo(CO)2 (3) (p-Cymene = η6-4-isopropyl-toluene) have been synthesized from the reactions of 16-electron half-sandwich ruthenium 1,2-dichalcogenolate carborane complexes (p-Cymene)Ru[E2C2(B10H10)] (E = S(1a), Se(1b)) with Mo(CO)3(Py)3 in the presence of BF3 · Et2O. The complexes of 2 and 3 were characterized by elemental analysis and IR, NMR spectra. The molecular structure of 2 has been characterized by single-crystal X-ray diffraction analysis. Complex 2 is unsymmetrical and the two Ru–Mo single bonds (2.7893(14), 2.8189(13) Å) are each supported by a symmetrically bridging o-carborane-1,2-dithiolato ligand.  相似文献   

14.
Two series of novel bis(indole) analogues viz., N′-((5-substituted-1H-indol-3-yl)methylene)-n-(1H-indol-3-yl)alkanehydrazides (7af) and N′-((5-substituted-1-(3-methylbut-2-enyl)-1H-indol-3-yl)methylene)-n-(1H-indol-3-yl)acetohydrazide (8af) were synthesized and characterized by spectral analysis. The target molecules were screened for their antimicrobial, anticancer activities and structure and activity relationship (SAR) was investigated. Compounds 7a, 7c and 8a were found to be active in antimicrobial screening. Anticancer screening reveals that Compound 7c was active against HeLa cell line with an IC50 of 43.1 μM and compound 7d was found to be interesting candidate with an IC50 of 26.0 and 30.2 μM against Colo-205 and Hep G2 cell lines respectively.  相似文献   

15.
《Solid State Sciences》2007,9(11):1012-1019
Two novel inorganic–organic hybrid compounds composed of Keggin tungstocobaltate framework and cobalt(II)–N coordination complexes, K[Co(phen)2(H2O)]2[HCoW12O40]·2H2O (1) (phen = 1,10-phenanthroline) and [Co(2,2′-bipy)3]1.5{[Co(2,2′-bipy)2(H2O)][HCoW12O40]·0.5H2O (2) (bipy = bipyridine), have been synthesized under hydrothermal conditions by directly using Keggin POMs as starting materials, which were characterized by elemental analyses, IR, TG analyses and X-ray single crystal diffraction. Crystal data for compound 1: C48H41Co3KN8O44W12, triclinic, space group P-1, a = 10.918(5) Å, b = 13.401(5) Å, c = 13.693(5) Å, α = 69.291(5)°, β = 71.568(5)°, γ = 78.421(5)°, V = 1768.9(12) Å3, Z = 1; for compound 2: C130H104Co7N26O83W24, orthorhombic, space group, C2/c, a = 46.839(9) Å, b = 14.347(3) Å, c = 26.147(5) Å, α = β = γ = 90°, V = 17,570(6) Å3, Z = 4. Compound 1 exhibits a pseudo-1D chainlike structure, in which potassium ions act as linkages of Keggin unit doubly grafted by [Co(phen)2(H2O)] complex. Compound 2 represents a [Co(2,2′-bipy)2(H2O)]2+ mono-grafted Keggin tungstocobaltate derivative with 1.5[Co(2,2′-bipy)3]2+ countercations. The cyclic voltammetric behavior of 1-CPE is similar to the parent 3-CPE, but the cyclic voltammetric behavior of CoII shows a little difference. Variable-temperature magnetic susceptibility measurement of compound 1 demonstrates the presence of antiferromagnetic interactions.  相似文献   

16.
The crystal structures of N-o-hydroxybenzimido-meso-tetraphenylporphyrinatozinc(II) toluene solvate [Zn(N-NCO(o-OH)C6H4-tpp)·C6H5CH3; 4·C6H5CH3], N-o-hydroxybenzimido-meso-tetraphenylporphyrinatonickel(II) chloroform solvate [Ni(N-NCO(o-OH)C6H4-tpp)·0.6CHCl3; 5·0.6 CHCl3], N-o-hydroxybenzimido-meso-tetraphenylporphyrinatocopper(II) toluene solvate [Cu(N-NCO(o-OH)C6H4-tpp)·C6H5CH3; 6·C6H5CH3] and N-o-oxido-benzimido-meso-tetraphenylporphyrinato(-κ4,N1,N2,N3,N5,κO2) manganese (III) methylene chloride·methanol solvate [Mn(N-NCO(o-O)C6H4-tpp)·CH2Cl2·MeOH; 8·CH2Cl2·MeOH] were established. The coordination sphere around Zn2+ ion in 4·C6H5CH3, (or Ni2+ ion in 5·0.6 CHCl3 or Cu2+ ion in 6·C6H5CH3) is a distorted square planar (DSP) whereas for Mn3+ in 8·CH2Cl2·MeOH, it is a distorted trigonal bipyramid (DTBP) with O(1), N(1) and N(3) lying in the equatorial plane for 8·CH2Cl2·MeOH. The g value of 8.27 measured from the parallel polarization of X-band EPR spectra at 293 K is consistent with the high-spin mononuclear manganese(III) (S = 2) in 8. The magnitude of axial (D) zero-field splitting (ZFS) for the mononuclear Mn(III) in 8 was determined approximately as 3.0 cm?1 by the paramagnetic susceptibility measurements and conventional EPR spectroscopy.  相似文献   

17.
3-(2-Chloroquinolin-3-yl)-1,5-bis(3,4,5-trimethoxy-phenyl)-pentane-2,4-dione derivatives 3a–b were conveniently synthesized in excellent yields (82% each) by tandem Knoevenagel condensation reactions of 2-chloro-3-carbaldehyde-quinoline 1ab with 3,4,5-trimethoxy acetophenone, followed by a base catalyzed Michael addition, such as DBU (1,8-diazabicyclo[5,4,0]undec-7-ene) with or without solvent. The reactions of 3a–b with Pd(dba)2 in the presence of PPh3 (1:2) in degassed acetone provided the dinuclear palladium complexes {Pd(C,N-2-C9H4N–CH–[–CH2CO(3,4,5-(OMe-)3–C6H2-]2–3-R-6)Cl(PPh3)}2 [(R = H (4a), R = OMe (4b)] in moderate yields (38% and 43%), which in turn reacted with an excess of isonitrile XyNC (Xy = 2,6-Me2C6H3) to give the corresponding palladacycles 5ab in moderate yields (45% and 43%). The palladacycles 5ab were also obtained in similar yields (32% and 33%) via a one-pot oxidative addition reaction of 3a-b with isonitrile XyNC:Pd(dba)2 (4:1). The products were characterized by satisfactory elemental analysis and spectral studies (IR, 1H, and 31P NMR). The crystal structure of 5a was determined by X-ray crystallography diffraction studies.  相似文献   

18.
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.
《Tetrahedron: Asymmetry》2006,17(17):2516-2530
(S)-(−)-(Benzotriazol-1-yl)- and (S)-(−)-(benzotriazol-2-yl)-alkan-2-ols 7a9a, 7b9b and their (R)-(+)-acetates 10a12a and 10b–12b were prepared in high enantiomeric excess via lipase from Pseudomonas fluorescens (Amano AK) catalyzed enantioselective acetylation of racemic alcohols 4a6a and 4b6b with vinyl acetate in tert-butyl methyl ether or toluene at 23 °C. The enantioselectivity of this transformation was dependent on the length of the alkyl chain with E-values ranging from 30 to 57. Several benzotriazole substituted ketones 1a3a and 1b3b were synthesized from 1H-benzotriazole and corresponding haloketones. These compounds were stereoselectively reduced with Baker’s yeast in water or in organic solvent containing 5% v/v of water at 30 °C to give the (S)-(−)-alcohol. Better stereoselectivity was observed in the kinetic resolution of racemic alcohols 4a6a and 4b6b (ee = 69–92% at 44–52% conversion) compared to reduction of corresponding prochiral ketones 1a3a and 1b3b with Baker’s yeast (ee = 40–67% at 39–89% conversion). Enhanced enantioselectivities were observed at lower temperatures.  相似文献   

20.
The carbosilanes RMe2Si(CH2)xSiH3, [R = 2-Th (1a, 2a), 4-Me-2-Th (3a, 4a), 2-Fu (5a, 6a), 5-Me-2-Fu (7a, 8a); x = 2 and 3], with primary SiH3 end groups undergo a facile dehydropolymerization under ambient conditions (50 °C, 48 h) in presence of Cp2TiCl2/2.2 n-BuLi catalyst to afford the corresponding poly(hydrosilane)s 1–8 bearing carbosilyl side chains appended with thienyl/furyl groups. These have been characterized by GPC, IR, multinuclear (1H, 13C{1H}, 29Si{1H}) NMR, UV and PL spectral studies.  相似文献   

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