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1.
The synthesis of the new potentially pentadentate ligand, 2,2??-(2-methyl-2-(pyridin-2-yl)propane-1,3-diyl)bis(sulfanediyl)diethanamine (L 1 ), containing two thioether sulfurs, two ?CNH2 amines and a pyridyl nitrogen heteroatom is described. Reaction of L 1 with copper(II) chloride and addition of hexafluorophosphate anion has led to isolation of the mixed anion complex Cu2(L 1 )2Cl(PF6)3. The synthesis and X-ray structure of cobalt(III) species, [Co(L 1 )Cl](PF6)2, is also reported. In situ reaction of L 1 with copper(II) as a metal template in the presence of formaldehyde and the carbon acid nitroethane together with triethylamine (as base) led to macrocycle ring closure to yield [Cu(L 2 )Cl]PF6 (where L 2  = 6,13-dimethyl-6-nitro-13-(pyridin-2-yl)-1,11-dithia-4,8-diazacyclotetradecane) whose X-ray structure shows that the copper centre has a distorted square pyramidal coordination geometry being bound by both ?CNH2 nitrogens and both sulfurs of L 2 while the pyridyl nitrogen remains uncoordinated.  相似文献   

2.
The interaction of Cu(II), Fe(III) and Co(III) with 6,6,13-trimethyl-13-amino-1,4,8,11-tetraazacyclotetradecane (L 3 ) incorporating a pendent amine group has led to isolation of the new octahedral complexes [Cu(HL 3 )(ClO4)2]Cl·H2O (1), [Fe(L 3 )Cl](S2O6)·H2O (2), [Co(L 3 )Cl](ClO4)1.5Cl0.5·0.25H2O (3), [Co(HL 3 )Cl2](ClO4)2·H2O (4) and [Co(L 3 )Cl]2(S2O4)(ClO4)2 (5). In (1) the copper ion occupies the macrocyclic cavity of protonated (–NH3 +) L 3 which is present in its trans-III configuration; weakly bound ClO4 ? ligands occupy the axial positions. The X-ray structure of (2) showed that Fe(III) occupies the N4-macrocyclic cavity of L 3 in a trans-III configuration, with the pendent amine group binding in an axial position. The remaining axial position is occupied by a Cl? ligand. Chromatography of the product obtained from the reaction of Na3[Co(CO3)3] with L 3 yielded three fractions. Fraction 1 yielded crystals (3) composed of three crystallographically independent species incorporating cations of type [Co(L 3 )Cl]2+ with very similar structures; in each case the macrocyclic ring nitrogens of L 3 are bound to the Co(III) in an asymmetric cis-fashion. Fraction 2 yielded the trans-III octahedral cationic complex (4) incorporating L 3 in its protonated form. The Co(III) complex (5) from fraction 3 shows a different coordination arrangement to the products from fractions 1 or 2. The macrocyclic ring coordinates in its trans-III form, but the axial sites in this case are occupied by the pendent-NH2 group and a Cl? ligand.  相似文献   

3.
Cyanuration of 2-naphthaldehyde (1) and 5-methyl-2-furaldehyde (2) yielded the racemic 2-hydroxy-2-(β-naphthyl)ethanenitrile (R,S)-3 and 2-hydroxy-2-(5-methyl-2-furyl)ethanenitrile (R,S)-5, respectively. The same reaction can be completed by using acetone cyanohydrin (4) as a transcyanating agent. The optically active (R)-3 and (S)-5 could be respectively obtained by hydrocyanation of 1 and 2 using (R)-hydroxynitrile lyase (R)-PaHNL [EC 4.1.2.10] from almonds (Prunus amygdalus) as a chiral catalyst. Cyanohydrins 3 and 5 in their racemic and optically active forms undergo a number of transformations which involve either the hydroxyl group or the cyanide function. Moreover, derivatization of 3 and 5 with (S)-Naproxen®chloride (S)-14 gave the respective diastereoisomers. The optical activity of (R)-3 and (S)-5 as well as their derivatives were recorded. The postulated structures for the new products were supported with compatible elementary and spectroscopic (IR, 1H NMR, 13C NMR, MS, and single crystal X-Ray crystallography) analyses. The antimicrobial activity of some selected racemic new products and their respective optically active analogues were also undertaken.  相似文献   

4.
<正>1 General procedure for the preparation of 3-substituted glutaronitriles To a 100 mL flask containing aldehyde(30 mmol) and cyanoacetic acid(10.20 g, 120 mmol) was added 4-methylpiperidine(0.4 mL) and 23 mL N-methylmorpholine. The reaction mixture was warmed to mild reflux for 24 h and then cooled to room temperature and concentrated on a rotary evaporator. The resulting mixture was dissolved in 100  相似文献   

5.
The reactions of GeCl4, GeBr4, and MeGeCl3 with O-trimethylsilyl derivatives of N,N-disubstituted amides of 2-hydroxycarboxylic acids afforded pentacoordinate and hexacoordinate neutral (O,O)-mono- and (O,O)-bischelates. The reactions of glycolic acid derivatives with GeX4 produced bischelates X2Ge[OCH2C(O)NR2R3]2 7a,c,d (X = Cl, R2 = R3 = Me (a), (CH2)5 (c), (CH2CH2)2O (d)) and 8a (X = Br). By contrast, the reactions of lactic and mandelic acid derivatives with GeCl4 and MeGeCl3 gave monochelates Cl3Ge[OCH(R1)C(O)NR2R3] (S)-9a–c (R1 = Me) and Cl2MeGe[OCH(R1)C(O)NR2R3] 10a (R1 = H), (S)-11a,b (R1 = Me), and (S)-12a (R1 = Ph) (R2R3 = (CH2)4 (b)), respectively. According to the X-ray diffraction data, the Ge atom in bischelates 7c,d and 8a has a coordination number 6, and its coordination polyhedron can be described as a slightly distorted octahedron. In monochelates (S)-9a-c, 10a, (S)-11a,b, and (S)-12a, the Ge atom has a coordination number 5, and its coordination polyhedron can be described as a trigonal bipyramid with two halogen atoms or one halogen atom and one ethereal oxygen atom in equatorial positions and the halogen atom and the amide oxygen atom in the axial positions. The bonds in the axial positions are somewhat longer than the corresponding bonds in tetracoordinate Ge compounds.  相似文献   

6.
Oxidation of the α- and β-4-phenyl-1,2,4-triazolin-3,5-dione adducts of vitamin D3 (2 and1) withMCPBA yields two diastereomeric mixtures of the (5,10)-(7,8)-dioxiranes3 a,3 b,3 c and4 a,4 b respectively. The corresponding benzoates5 a,5 b,6 a and6 b were prepared and the X-ray crystal structure of5 b was determined. This analysis proved5 b to be the (5R, 1 OS)-(7R, 8R)-dioxirane of the β-resp. (6S)-4-phenyl-1,2,4-triazolin-3,5-dione adduct1 of vitamin D3.  相似文献   

7.
The oxalato-bridged dicopper(II) complexes [Cu2(μ-ox)(LRR)2(H2O)2(ClO4)2] (1),[Cu2(μ-ox)(LRR)2(CH3COCH3)2(ClO4)2](1a),[Cu2(μ-ox)(LSS)2(H2O)2(ClO4)2] (2) and [Cu2(μ-ox)(LRR)(LSS)2(CH3COCH3)2(ClO4)2] (3) [LRR = (8R,10R)-(-)-[4,5]-pineno2,2′-bipyridine,LSS = (8S,10S)-(+)-[4,5]-pineno-2,2′-bipyridine;ox2= oxalate] were first prepared.A possible mechanism for the formation of the chial dicopper(II) complexes was proposed.Based on elemental analysis,conductance measurement,UV-Vis spectra,CD spectra and X-ray single-crystal diffraction,the oxalato-bridged structures of 1 and 2 were deduced to adopt two Cu(II) ions and the bridged oxalate lying in the nearly same plane.The crystal structures of 1a and 3 reveal that the coordination geometry around each Cu(II) ion is an elongated and distorted octahedron and two axial solvent molecules and two perchlorate ions are anti to each other respectively in both binuclear molecules.The solution CD spectra of 1 and 2 in the visible d-d range show very weak Cotton effects with peaks at 588 and 779 nm,which are approximately of mirror image,suggesting the optical activities may be derived from the vicinal effects of the chiragenic centers at the pinene group of LRR and LSS,respectively.Complex 1 has been characterized by variable-temperature magnetic susceptibility and the data was least-square fitted to the Blenaey-Bowers equation.The exchange integral J was found to be -338.41(4) cm-1,indicating a strong antiferromagnetic interaction between two copper(II) ions.  相似文献   

8.
A straightforward synthesis of (2S)-[3,3-2H2]-proline 1c and (2S,3R)- and (2S,3S)-[3-2H1]-proline, 1b and 1a, respectively, has been devised. The key step of the route to the latter compounds involves highly stereoselective hydrolysis of the silyl enol ethers 3 and 3a, respectively, with protonation (deuteriation) from the re-face of the silyl enol ether.  相似文献   

9.
The reactions of N-(aryl)pyridine-2-aldimines (L-R; R = OCH3, CH3, H, Cl and NO2), derived from pyridine-2-aldehyde and para-substituted anilines, with CuI in methanol under ambient conditions afford a series of brown complexes of the type [{Cu(L-R)I}2]. The structure of the [{Cu(L-OCH3)I}2] complex has been determined by X-ray crystallography. In these dimeric complexes the two copper centers are linked through an iodo-bridge, and the L-R ligands are coordinated to the metal center through the pyridine-nitrogen and imine-nitrogen. All the complexes show characteristic 1H NMR signals and intense MLCT transitions in the visible region. These complexes also show an emission near 465 nm, whilst they are excited at 340 nm, with relatively poor quantum yields (φ ∼0.002 at 298 K). Cyclic voltammetry on all the complexes shows two successive Cu(I)-Cu(II) oxidations on the positive side of SCE, and a reduction of the coordinated imine ligand on the negative side. These copper(I) complexes are found to efficiently catalyze Suzuki type C-C coupling reactions.  相似文献   

10.
Reactions of 3,6-bis(2-pyridyl)-4-phenylpyridazine (Lph) with [(η6-arene)Ru(μ-Cl)Cl]2 (arene = C6H6, p-iPrC6H4Me and C6Me6), [(η5-C5Me5)M(μ-Cl)Cl]2, (M = Rh and Ir) and [(η5-Cp)Ru(PPh3)2Cl] (Cp = C5H5, C5Me5 and C9H7) afford mononuclear complexes of the type [(η6-arene)Ru(Lph)Cl]PF6, [(η5-C5Me5)M(Lph)Cl]PF6 and [(Cp)Ru(Lph)(PPh3)]PF6 with different structural motifs depending on the π-acidity of the ligand, electronic properties of the central metal atom and nature of the co-ligands. Complexes [(η6-C6H6)Ru(Lph)Cl]PF61, [(η6-p-iPrC6H4Me)Ru(Lph)Cl]PF62, [(η5-C5Me5)Ir(Lph)Cl]PF65, [(η5-Cp)Ru(PPh3)(Lph)]PF6, (Cp = C5H5, 6; C5Me5, 7; C9H7, 8) show the type-A binding mode (see text), while complexes [(η6-C6Me6)Ru(Lph)Cl]PF63 and [(η5-C5Me5)Rh(Lph)Cl]PF64 show the type-B binding mode (see text). These differences reflect the more electron-rich character of the [(η6-C6Me6)Ru(μ-Cl)Cl]2 and [(η5-C5Me5)Rh(μ-Cl)Cl]2 complexes compared to the other starting precursor complexes. Binding modes of the ligand Lph are determined by 1H NMR spectroscopy, single-crystal X-ray analysis as well as evidence obtained from the solid-state structures and corroborated by density functional theory calculations. From the systems studied here, it is concluded that the electron density on the central metal atom of these complexes plays an important role in deciding the ligand binding sites.  相似文献   

11.
Complexes of three related 1-azapentadienyl ligands [N(SiMe2R1)C(But)(CH)3SiMe2R], abbreviated as L (R = But, R= Me), L′ (R = Me = R1), and L″ (R = But = R1), are described. The crystalline compounds Sn(L)2 (1), Sn(L′)2 (2), [Sn(L′)(μ-Cl)]2 (3) and [Sn(L″)(μ-Cl)]2 (4) were prepared from SnCl2 and 2 K(L), 2 K(L′), K(L′) and K(L″), respectively, in thf. Treatment of the appropriate lithium 1-azapentadienyl with Si(Cl)Me3 yielded the yellow crystalline Me3Si(L) (5) and the volatile liquid Me3Si(L′) (6) and Me3Si(L″) (7), each being an N,N,C-trisilyldieneamine. The red, crystalline Fe(L)2 (8) and Co(L′)2 (9) were obtained from thf solutions of FeCl2 with 2 Li(L)(tmeda) and CoCl2 with 2 K(L′), respectively. Each of 1-9 gave satisfactory C, H, N analyses; 6 and 7 (GC-MS) and 1, 2, 8 and 9 (MS) showed molecular cations and appropriate fragments (also 3 and 4). The 1H, 13C and 119Sn NMR (1-4) and IR spectra support the assignment of 1-4 as containing Sn-N(SiMe2R1)-C(But)(CH)3SiMe2R moieties and 5-7 as N(SiMe3)(SiMe2R1)C(But)(CH)3SiMe2R molecules; for 1-4 this is confirmed by their X-ray structures. The magnetic moments for 8 (5.56 μB) and 9 (2.75 μB) are remarkably close to the appropriate Fe and Co complex [M{η3-N(SiMe3)C(But)C(H)SiMe3}2]; hence it is proposed that 8 and 9 have similar metal-centred, centrosymmetric, distorted octahedral structures.  相似文献   

12.
The complexes trans-[RuCl2(L){(S,S)-iPr-pybox}] ((S,S)-iPr-pybox = 2,6-bis[4′-(S)-isopropyloxazolin-2′-yl]pyridine, L = PMe3 (1), P(OMe)3 (2), PPh2(CH2CHCH2) (3), CNBn (5), CNCy (6) and MeCN (7)) have been synthesized by substitution of ethylene on the precursor trans-[RuCl2(η2-C2H4){(S,S)-iPr-pybox}]. This complex also reacts with cyclooctadiene (cod) or norbornadiene (nbd) and NaPF6, in refluxing methanol, giving the coordination compounds [RuCl(η4-cod){(S,S)-iPr-pybox}][PF6] (8) and [RuCl(η4-nbd){(S,S)-iPr-pybox}][PF6] (9). The structures of complexes [RuCl(CO)(PPh3)(H-pybox)][BF4] (H-pybox = 2,6-bis(dihydrooxazolin-2′-yl)pyridine) (4), 6 and 8, have been resolved by X-ray diffraction methods. The catalytic activity of the new complexes in transfer hydrogenation of acetophenone has also been examined.  相似文献   

13.
Trimethyl (2S,3R)- and (2R,3R)-[2-2H1]-homocitrates, 10b and 10c respectively, and dimethyl (2S,3R)- and (2R,3R)-[2-2H1]-homocitric lactones, 11b and 11c respectively, have been synthesised from shikimic acid and [2-2H]-shikimic acid by a route which defines the stereochemistry of the two chiral centres in each compound. The NMR spectra of these products will enable the stereochemistry of the biological reaction catalysed by homocitrate synthase and by the protein from the nifV gene to be elucidated.  相似文献   

14.
Some mixed ligand copper(I) complexes of general formula [Cu(L)(PPh3)3]X (X = Cl (1), ClO4 (2), BF4 (3) or PF6 (4); L = 2-(benzen-1-yl)methyleneamino-3-aminomaleonitrile) were prepared and characterized by physicochemical and spectroscopic methods. A single-crystal X-ray diffraction study of [Cu(L)(PPh3)3]CIO4 (2) revealed that the copper atom is four coordinated in a distorted tetrahedral geometry. Electrochemical studies of complexes 14 show quasireversible redox behavior corresponding to the Cu(I)/Cu(II) couple. Room temperature luminescence is observed for all four complexes. These complexes proved to be effective catalysts for the Sonogashira coupling of terminal alkynes with aryl halides at 90 °C.  相似文献   

15.
The self-assembly of unsymmetrical tecton 3-nitro-5-(pyridin-4-yl)benzoic acid (HL)with cobalt chloride under hydrothermal conditions affords a new 2D coordination polymer [Co(L)2] n (1, L = 3-nitro-5-(pyridin-4-yl)benzoate), which is characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction analysis, and single crystal X-ray diffraction. Compound 1 is of the triclinic system, space group P-1 with a = 9.7857(12) Å, b = 10.3417(13) Å, c = 10.8463(13) Å, α = 85.155(2)°, β = 74.785(2)°, γ = 88.962(2)°, V = 1055.4(2) Å3. The crystal structural analysis of complex 1 shows that the cobalt center is six-coordinated in an octahedral geometry by four O atoms from four different L ligands and two N atoms from two different L ligands; the Co(II) cations are bridged by μ3-L into an interesting two-dimensional network structure. It should be pointed out that the thermal analysis results indicate that complex 1 is quite stable up to 420°C.  相似文献   

16.
The flexible ditopic ligand 1,2-bis(3-(4-pyridyl)pyrazol-1-yl)ethane (L4Et) displays remarkable versatility in the complexes that it forms with transition metals with products ranging from 1D chains to interpenetrating 3D networks. The L4Et ligand itself crystallises in the space group P21, adopting a helical twist, although it is found in a variety of other conformations in its complexes. Coordination polymers containing the L4Et ligand vary from almost straight, parallel 1D chains of [Ag2(L4Et)2(ClO4)2(DMF)]·DMF (1), through interdigitating helical complexes containing tetrahedral Zn(II), [Zn(NCS)2(L4Et)]·DMF·H2O (2) to 2D sheets of [Cu(L4Et)2(H2O)2](PF6)2·xH2O (3) and the three-fold interpenetrating 3D network of [Co(L4Et)2(NCS)2] (4). The 3D network adopts an unusual 3D 4-connected dmp (65.8) topology. Dimensionality can be limited by the use of chelating co-ligands, demonstrated by the formation of the dinuclear complex [{Cu(py-2,6-CO2)(H2O)}2(L4Et)] (5).  相似文献   

17.
A novel versatile tridentate 3-(aminomethyl)naphthoquinone proligand, 3-[N-(2-pyridylmethyl)aminobenzyl]-2-hydroxy-1,4-naphthoquinone (HL), was obtained from the Mannich reaction of 2-hydroxy-1,4-naphthoquinone (Lawsone) with 2-aminomethylpyridine (amp) and benzaldehyde. The reactions of HL with CuCl2·2H2O yielded two novel dinuclear copper(II) complexes, [Cu(L)(H2O)(μ-Cl)Cu(L)Cl] (1b), [CuCl(L)(μ-Cl)Cu(amp)Cl] (2) and a polymeric compound, [Cu(L)Cl)]n (1a), whose relative yields were sensitive to temperature, reagents concentration and presence of base. The crystalline structures of 1b and 2 were determined by X-ray diffraction studies. The two copper atoms in complex 1b are connected by a single chloro bridge with a Cu?Cu separation of 4.1342(8) Å and Cu(1)–Cl(1)–Cu(2) angle of 109.31(4)°. In complex 2 the two copper atoms are held together by a chloro and a naphthalen-2-olate bridges [Cu(1)–Cl(2)–Cu(2) and Cu(1)–O(1)–Cu(2) angles being 83.31(3) and 109.70(9)°, respectively, and the Cu?Cu separation, 3.3476(9) Å]. As expected, variable-temperature magnetic susceptibility measurements of complex 1b showed weak antiferromagnetic intramolecular coupling between the copper(II) centers, with J = −5.7 cm−1, and evidenced for complex 2 strong antiferromagnetic coupling, with J ∼ −120 cm−1. Furthermore, the magnetic behaviour of compound 1a suggested an infinite 1D coordination polymeric structure in which the copper(II) centers are connected by Cl–Cu–Cl bridges. Solution data (UV–Vis spectroscopy and cyclic voltammetry) indicated structural changes of 2 and 1a in CH3CN, and evidenced conversion of polymer 1a into dimer 1b.  相似文献   

18.
A novel and simple process for the preparation of enantiomerically pure (SS)-benzenesulfinamide (SS)-3a, (SS)-p-toluenesulfinamide (SS)-3b, (SS)-p-chloro-benzenesulfinamide (SS)-3c and (SS)-p-fluorobenzenesulfinamide (SS)-3d has been developed. The treatment of arylsulfinyl chlorides with (R)-N-benzyl-1-phenylethanamine in the presence of excess triethylamine gave diastereomeric mixtures of N-benzyl-N-(1-phenylethyl)-arylsulfinamides 1, which underwent spontaneous crystallization to furnish diastereomerically pure (R,SS)-N-benzyl-N-(1-phenylethyl)-arylsulfinamides (R,SS)-1a-1d in 28%, 29%, 27% and 31% yields, respectively. The diastereomerically pure compounds (R,SS)-1 were then converted into four enantiopure (RS)-methyl arylsulfinates (RS)-2, and finally into four enantiopure (SS)-arylsulfinamides (SS)-3 in good yields.  相似文献   

19.
The reactivity of (3,5-dimethyl-1H-pyrazol-1-yl)ethyldiphenylphosphine (L) hybrid ligand against Cu(I), Ag(I) and Au(I) has been assayed and compounds [Cu(L)2](PF6) (1), [Ag(L)]2(PF6)2·2C2H4Cl2·2C4H10O (2) and [AuCl(L)]2 (3) have been isolated and fully characterised. A fully characterisation by analytical and spectroscopic methods of 1-3 are presented and X-ray crystal structures of 1 and 2 are also reported. The similar data obtained between 2 and 3 permits to do a serious purpose of the structure of 3 in solid and solution.  相似文献   

20.
Heteroligand binuclear complexes of CuCl with triphenylphosphine and 5-pyridine-2-yl-5,6-dihydro-[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione (L1) of the compositions [CuCl(PPh3)(L1)]2 (I) and [CuCiL1]2 (II) are synthesized and studied by X-ray diffraction method. Crystals I are monoclinic; space group P21/n, a=8.9520(18) Å, b=18.926(4) Å, c=16.841(3) Å, β=94.96(3)°, Z=2. The Cu(I) atom has a quasi-tetrahedral surrounding involving the tetraphenylphosphine P atom, the pyridyl N atom of the molecule L1, and two bridging Cl atoms. Crystals II are monoclinic; space group P21/c, a=9.3520(19) Å, b=8.1490(16) Å, c=18.660(4) A, β = 104.43(3)°, Z = 2. Both L1 ligands in complex II act as bridges. The Cu(I) atom also has a quasi-tetrahedral surrounding formed by the Cl atoms, the pyridyl N atoms and thiol S atom of one L1 ligand, and the thione S atom of the second L1 ligand. Similar binuclear complexes with the bridging function of the L1 ligand were also detected in a solution of II by the ESI method.  相似文献   

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