Search

The title complex, [Cu(C21H38N5Si)(C18H15P)], was obtained from the one-pot reaction between (Dipp)N(Li)SiMe3 (Dipp = 2,6-diisopropylphenyl), Me2NCN, CuCl and PPh3. The CuI atom has a distorted trigonal–planar coordination sphere. The triazapentadienyl ligand acts as a κ2-donor. The N—Cu—N bond angle is 95.88 (14)°. In the triazapentadienyl fragment, the C—N bond lengths are in the range 1.328 (5)–1.349 (5) Å, which indicates delocalization of the π-electrons in the NCNCN system.

In the title compound, C13H12N4O3, the dihedral angle between the planes of the pyrrole and benzene rings is 7.47 (1)°. In the crystal, molecules are arranged in sheets lying parallel to (101). Neighbouring sheets are linked by N—H...O hydrogen bonds, weak π–π [centroid–centroid distance between the pyrrole rings = 3.765 (11) Å] and C—H...π interactions, forming a three-dimensional structure.

A new oxidovanadium(V) complex, [VOL(OEt)(EtOH)] (1), and a new dioxidomolybdenum(VI) complex, [MoO2L(OH2)] (2), where L is the dianionic form of 2-bromo-N'-(3,5-dichloro-2-hydroxybenzylidene)benzohydrazide, have been synthesized and structurally characterized by physico-chemical methods and single crystal X-ray determination. X-ray analysis indicates that the V and Mo ions in the complexes are in octahedral coordination. Crystal structures of the complexes are stabilized by hydrogen bonds. The catalytic property for epoxidation of styrene by the complexes was evaluated. Both complexes have effective catalytic properties for the epoxidation of styrene, with conversions over 76% and selectivities over 92%. [ABSTRACT FROM AUTHOR]

Reaction of silver nitrate with 2‐aminobenzothiazole (abbreviated as Habt) in methanol at 45°C gave mononuclear complex of formula [Ag (Habt)2]NO3•CH3OH. The structure of the complex was characterized by infrared (IR) spectra, single crystal X‐ray diffraction, and elemental analysis. X‐ray diffraction analysis indicated that the title complex was crystallized in the triclinic crystal system with space group P–1, in which silver(I) ion was coordinated to two 2‐aminobenzothiazole ligands through the benzothiazol nitrogen atom. Theoretical study of the complex was carried out by density functional theory (DFT) B3LYP method. The antimicrobial effects of the ligand and its silver(I) complex were evaluated by bio‐microcalorimetry on the growth of Schizosaccharomyces pombe (S. pombe). Some quantitative metabolic parameters, such as growth rate constant (k), maximum heat power (Pmax), inhibition ratio (I), and half inhibition concentration (IC50), were derived from the metabolic power–time curves of S. pombe growth. The half inhibition concentration (IC50) of the ligand was calculated to be 2.58 × 10−3 mol L−1. The complex could strongly influence the lag phase of S. pombe. [ABSTRACT FROM AUTHOR]

Five new copper(II), nickel(II) and zinc(II) complexes derived from 2-((2-(pyrrolidin-1-yl)ethylimino)methyl)phenol were synthesized and structurally characterized. Single crystal X-ray analysis indicates that the Cu atoms in the tetranuclear complexes 1 and 2 are in a square pyramidal coordination, the Ni atoms in the trinuclear complexes 3 and 4 are in an octahedral coordination and the Zn atom in the mononuclear complex 5 is in a tetrahedral coordination. In vitro bacterial viability revealed that the copper and zinc complexes have effective antimicrobial activity against B. subtilis , S. aureus , E. coli and P. fluorescens , and general activity against the fungal strains C. albicans and A. niger. [Display omitted] Five new copper(II), nickel(II) and zinc(II) complexes, [Cu 4 Cl 2 (μ 1,1 -N 3) 4 (DMF) 2 ] (1), [Cu 4 Br 2 (μ 1,1 -N 3) 4 (DMF) 2 ] (2), [Ni 3 L 2 (CH 3 COO) 4 ]CH 3 OH (3), [Ni 3 L 2 (CH 3 COO) 2 (μ 1,1 -N 3) 2 (CH 3 OH) 2 ] (4) and [Zn(LH)I 2 ]CH 3 OH (5), were designed and successfully synthesized using the Schiff base ligand 2-((2-(pyrrolidin-1-yl)ethylimino)methyl)phenol (HL). All the synthesized complexes were characterized using different physico-chemical and spectroscopic methods, like elemental analysis, infrared spectra and single crystal X-ray diffraction. The X-ray structural analysis showed that the Cu atoms in the tetranuclear complexes 1 and 2 are in a square pyramidal coordination, the Ni atoms in the trinuclear complexes 3 and 4 are in an octahedral coordination and the Zn atom in the mononuclear complex 5 is in a tetrahedral coordination. The Schiff base ligand was coordinated to the metal atoms through the phenolate oxygen, imino nitrogen and/or pyrrolidine nitrogen atoms. The biological study indicated that the copper and zinc complexes have interesting antimicrobial activity against B. subtilis , S. aureus , E. coli and P. fluorescens , with MIC values of 0.6–2.3 μmol/L. [ABSTRACT FROM AUTHOR]

A novel binuclear oxidovanadium(V) complex [V2O2(μ-O)L2(OEt)2], where L is the deprotonated form of 2,4-dibromo-6-(5-methylamino-[1,3,4]thiadiazol-2-yl)phenol (HL), was prepared by the reaction of 2-(3,5-dibromo-2-hydroxybenzylidene)-N-methylhydrazinecarbothioamide (HL') and VO(acac)2 in ethanol. The ligand L' underwent a cyclization during the coordination, to form a new ligand L. Structure of the complex was characterized by physicochemical methods and single-crystal X-ray determination. Crystal of the complex crystallizes in hexagonal space group R-3, with a = b = 33.302(3) Å, c = 15.308(2) Å, α = β = 90°, γ = 120°, V = 14702(3) Å3, Z = 18, R1 = 0.0823, wR2 = 0.2064, S = 1.011. X-ray analysis indicates that the V atom in the complex is in an octahedral coordination environment, constructed by the phenolate O and thiadiazol N atoms of L, one oxido O atom, one bridging O atom, and one deprotonated ethanol O atom. The distance between the two V atoms is 3.365(1) Å. The complex has an effective catalytic property for the oxidation of several olefins. [ABSTRACT FROM AUTHOR]

Four new zinc(II) complexes derived from the bis-Schiff base ligand N,N' -bis(4-bromosalicylidene)-1,3-propanediamine have been synthesized and structurally characterized by elemental analysis, infrared spectra, as well as single crystal X-ray diffraction. X-ray analysis indicates that the Zn atoms in the complexes are in octahedral, tetrahedral and square pyramidal coordination. In vitro bacterial viability revealed that the complexes have effective antimicrobial activities against B. subtilis , S. aureus , E. coli and P. fluorescens. [Display omitted] A series of new zinc(II) complexes, [Zn 2 Cl 2 L(MeOH) 2 ] (1), [Zn 4 Cl 2 L 2 (N 3) 2 ] (2), [Zn 4 Br 2 L 2 (N 3) 2 ] (3) and [Zn 4 I 2 L 2 (N(CN) 2) 2 ] (4), where L is the dianionic form of N,N' -bis(4-bromosalicylidene)-1,3-propanediamine, have been synthesized and structurally characterized by elemental analysis, infrared spectra, as well as single crystal X-ray diffraction. X-ray analysis indicates that the Zn atoms in the dinuclear complex 1 are in octahedral and tetrahedral coordination, while in the tetranuclear complexes 2 , 3 and 4 are in square pyramidal and tetrahedral coordination. In vitro bacterial viability revealed that the complexes have effective antimicrobial activities against B. subtilis , S. aureus , E. coli and P. fluorescens , while weak activities against the fungal strains C. albicans and A. niger. [ABSTRACT FROM AUTHOR]

A new manganese(II) complex [MnL2(NCS)2]·2H2O with the Schiff base ligand derived from 3-bromosalicylaldehyde withN-cyclohexylpropane-1,3-diamine has been synthesized and structurally characterized by physicochemical methods and single-crystal X-ray determination. The crystal of the complex crystallizes in monoclinic space groupC2/c, witha= 24.749(2),b= 7.2957(7),c= 26.183(4) Å,β= 118.70(2)°,V= 4171.6(8) Å3,Z= 4,R1= 0.0893,wR2= 0.2305, GOOF = 1.084. X-ray analysis indicates that the complex is a mononuclear manganese species, which possesses crystallographic inversion center symmetry. The Mn atom, lying on the inversion center, is coordinated in an octahedral coordination by two phenolate O and two imine N atoms from two Schiff base ligands, and two thiocyanate N atoms. The catalytic property for epoxidation of styrene by the complex has also been tested. [ABSTRACT FROM PUBLISHER]

Two new dioxomolybdenum(VI) complexes [MoO2(Bhbz) (CH3OH)] (1) and [MoO2(Cnbz)(CH3OH)] (2) with the benzohydrazone ligands H2Bhbz and H2Cnbz derived from 5-chlorosalicylaldehyde with 4-nitrobenzohydrazide and 3-bromosalicylaldehyde with 2-hydroxybenzohydrazide, respectively, have been synthesized and structurally characterized by physicochemical methods and single crystal X-ray determination. The crystal of (1) crystallizes in triclinic space groupP-1, witha= 8.0014(9),b= 9.6294(10),c= 11.4204(12) Å,α= 89.193(2),β= 87.833(2),γ= 89.110(2)°,V= 879.11(16) Å3,Z= 2,R1= 0.0464,wR2= 0.1185,S= 1.051. The crystal of (2) crystallizes in monoclinic space groupP21/c, witha= 7.4108(3),b= 18.7901(7),c= 12.6293(5) Å,β= 104.4850(10)°,V= 1702.72(12) Å3,Z= 4,R1= 0.0236,wR2= 0.0576,S= 1.061. X-ray analysis indicates that the structures of both complexes are similar to each other. The molybdenum atom in each complex is in an octahedral coordination environment, constructed by two oxo groups and NO2donor set of the ligand, and one methanol O atom. The complexes have effective catalytic property for the oxidation of several olefins. [ABSTRACT FROM PUBLISHER]

Metal-directed assembly of naphthalene-1,4,5,8-tetracarboxylicacid (NTA) with different transition-metal salts in the presence ofammonia results in a series of one-dimensional metal–naphthalenediimidato(M–NDI) coordination polymers with the formulas of {[Ag(NDI)](NH4)}n(P1), [Zn(NDI)(NH3)2]n(P2), [Cd(NDI)(NH3)2]n(P3), [Co(NDI)(NH3)2]n(P4) and [Ni(NDI)(NH3)2]n(P5), respectively.It is worthwhile to mention that the 1D straight-line NDI–Ag(I)coordination polymer P1is formed stepwise from a dinuclearNDI–Ag(I) intermediate [Ag2(NDI)(NH3)2] (2AgNDI), where ammonia serves as a stabilizingreagent of Ag(I) ion and a weak base to remove the protons of NDIH2simultaneously. Furthermore, P1exhibits semiconductingproperties in the solid state which may originate from its all-parallel-alignedpacking structure (AAAA) which is different from the common ABAB packingmode for P2–P5and 2AgNDI. In addition, theoretic computational studies as well as X-ray photoelectronspectrometer spectra on P1and 2AgNDIhavealso been carried out. [ABSTRACT FROM AUTHOR]

Two new dioxomolybdenum(VI) complexes, [MoO2 (Cinh)(CH3OH)] (1) and [MoO2(Minh)(CH3OH)] (2), with the isonicotinohydrazone ligands H2Cinh and H2Minh derived from isonicotinohydrazide with 5-chlorosalicylaldehyde and 3-methoxysalicylaldehyde, respectively, have been synthesized and structurally characterized by physico-chemical methods and single crystal X-ray determination. The crystal of (1) crystallizes in triclinic space group P-1, with a = 6.553(2), b = 10.737(4), c = 12.907(4) Å, α = 68.021(2), β = 83.788(3), γ = 75.072(3)°, V = 813.6(5) Å3, Z = 2, R1 = 0.0291, wR2 = 0.0617, S = 1.044. The crystal of (2) crystallizes in monoclinic space group P21/n, with a = 6.792(2), b = 30.259(4), c = 7.920(3) Å, β = 93.703(3)°, V = 1624.3(8) Å3, Z = 4, R1 = 0.0501, wR2 = 0.1250, S = 1.087. X-ray analysis indicates that the structures of both complexes are similar to each other. The molybdenum atom in each complex is in an octahedral coordination environment, constructed by two oxo groups and NO2 donor set of the isonicotinohydrazone ligand, and one methanol O atom. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new cobalt(II) complex was synthesized and characterized. • Theoretical studies using DFT calculations. • The bioactivity of cobalt(II) complex was assessed by bio-microcalorimetry. • The complex displayed much stronger antibacterial activity than Schiff base. • Some thermokinetic parameters (k , P max , t G and Q total) were derived. A new cobalt(II) Schiff-base complex [Co(L) 2 ] was prepared by using equivalent molar of Schiff-base ligand [HL=(E)- N '-(2-hydroxy-3-methoxybenzylidene)isonicotinohydrazide] and CoCl 2 ·6H 2 O. The structure of the complex was characterized by single-crystal X-ray diffraction, IR, ESI-MS, elemental analysis and DFT method. X-ray crystal structure analysis showed that the complex crystallized in space group Pbca, with two symmetry-independent molecules. The experimental vibrational bands(IR) have been discussed and assigned based on DFT calculations. The antibacterial activity of Schiff base and its complex against S. pombe were assessed by bio-microcalorimetry at 32 °C. Some thermokinetic parameters (k , P max, t G and Q total) were derived from the metabolic power–time curves, and their quantitative relationship with the concentration were analyzed. The half inhibition concentration (IC 50) of Schiff base and its complex were calculated to be 1.18 × 10−2 mol L−1 and 1.07 × 10−3 mol L−1, respectively. The inhibition effect of the complex showed much stronger than that of Schiff base. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ternary composites containing PLLA, PBAT and CNFs were prepared. • PBAT and CNFs assembled into the "mutton kebab"-like structure during processing. • CNFs induced the epitaxial crystallization of PLLA on the surface of CNFs. • Highly-toughened, high heat resistant and self-healing properties were achieved. Biodegradable poly(L -lactic acid) (PLLA) based blend composites with excellent toughness exhibit comprehensive applications and they can be substitute for the common polyolefin and polyester based composites. To date, various strategies have been developed to enhance the toughness of the PLLA based blends or composites. Here, carbon nanofibers (CNFs) incorporated PLLA/poly(butylene adipate-co-butylene terephthalate) (PBAT) blend composites were investigated. The crystallinity of the PLLA matrix were precisely tailored through annealing treatment. Interestingly, CNFs and PBAT particles self-assembled into the "mutton kebab"-like structure during processing. In addition, the annealing treatment facilitated the epitaxial crystallization of PLLA on the surface of CNFs that were not covered by PBAT due to the excellent heterogeneous nucleation effect of CNFs. Consequently, with the addition of 1 wt% CNFs and tailoring the blend composite with the PLLA crystallinity of about 32.6%, the impact strength of the composite was increased by 270% from 10.0 kJ/m2 to 37.0 kJ/m2. The toughening mechanisms were mainly connected with the greatly strengthened interfacial interaction between PLLA matrix and PBAT particles by CNFs through CNFs bridging effect and CNFs inducing PLLA crystallization, facilitating the transfer of stress under the load condition, especially at high PLLA crystallinity. Furthermore, it was found that CNFs exhibited outstanding photothermal conversion effect, which could endow the blend composites with mechanical-damage-healing ability. This work not only reveals the role of crystalline structure in toughening of the PLLA-based blend composites but also paves an effective way to prepare super-toughened, biodegradable, heat resistant and mechanical-damage-healing PLLA-based composites via tailoring the crystalline structure of the matrix. [ABSTRACT FROM AUTHOR]