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On the basis of the Förster resonance energy transfer mechanism between rhodamine and quinoline–benzothiazole conjugated dyad, a new colorimetric as well as fluorescence ratiometric probe was synthesized for the selective detection of Cd2+. The complex formation of the probe with Cd2+was confirmed through Cd2+-bound single-crystal structure. Capability of the probe as imaging agent to detect the cellular uptake of Cd2+was demonstrated here using living RAW cells.

Heterocyclic chalcones containing thiophene moiety were synthesized and their chemical structures determined via IR, MS, 1H NMR and 13C NMR spectroscopy. Crystal structure of the compounds was determined using single crystal X-ray diffraction.The chalcones were also screened for in-vitro antifungal activity against two fungal strains; Candida albicans (MTCC 3958) and Aspergillus niger (MTCC 9933)which gave good results.

Background: A new series of pyrazole containing 1,4-dihydropyridine derivatives 5a-i and 6a-i were synthesized from substituted acetylated aryls and substituted phenylhydrazine by the multistep reaction. Method: The target compounds 1,4-dihydropyridine derivatives were obtained from green synthesis of 1,3-disubstituted phenyl-1H-pyrazole-4-carbaldehydes 4a-i with ethyl acetoacetate and methyl acetoacetate at higher temperatures in the presence of ammonium acetate and the catalytic amount of ammonium metavanadate (NH4VO3). The role of ammonium metavanadate was increases rate of the reaction and obtained high yields. Result: Structures of newly synthesized 1,4-dihydropyridine moiety containing pyrazole derivatives were confirmed by FT-IR, NMR and Mass spectral studies. The structure of compound 5b was confirmed by S-XRD study. Further, these compounds were tested for in-vitro antitubercular and antimicrobial studies. Compounds 5a, 5b, 5i, 6a, 6b, 6g, 6h, and 6i were found to be active against all the bacterial microorganisms. Conclusion: The above mentioned compounds have shown lowest MIC ranging between 3.12-12.5 μg/ml against Mycobacterium tuberculosis and MIC values ranging between 7.8- 15.6 μg/ml for Mycobacterium smegmatis, Staphylococcus aureus and Pseudomonas aeruginosa. For the control of life threatening diseases such as tuberculosis, these eight compounds may be strongly promising synthetic compounds.

AbstractPolysulfone and polyphenylsulfone-blend ultrafiltration membranes of different compositions were prepared by the phase inversion method, with and without hydrophilic additive poly (ethylene glycol) 1,000 (PEG). The membrane morphology was studied using scanning electron microscope, which displayed the asymmetric structure of the membrane. The hydrophilicity of the membranes was measured by contact angle, porosity, water uptake, and permeability studies. The blend membrane showed enhanced permeability, hydrophilicity, and antifouling property as compared to the pristine polymer membrane. The pure water flux of the membrane, which was blended with PEG additive was relatively higher than the blend membranes without the additive. The flux recovery ratio (FRR) was measured to study the antifouling property. The membranes with PEG additive exhibited better antifouling property with maximum FRR of 72.84%. The heavy metal rejection by the membrane was carried out by complexing the metal ions with polyethyleneimine, which exhibited highest rejection of 99.48 and 95.5% of Pb2+and Cd2+, respectively.

Polysulfone and polyphenylsulfone-blend ultrafiltration membranes of different compositions were prepared by the phase inversion method, with and without hydrophilic additive poly (ethylene glycol) 1,000 (PEG). The membrane morphology was studied using scanning electron microscope, which displayed the asymmetric structure of the membrane. The hydrophilicity of the membranes was measured by contact angle, porosity, water uptake, and permeability studies. The blend membrane showed enhanced permeability, hydrophilicity, and antifouling property as compared to the pristine polymer membrane. The pure water flux of the membrane, which was blended with PEG additive was relatively higher than the blend membranes without the additive. The flux recovery ratio (FRR) was measured to study the antifouling property. The membranes with PEG additive exhibited better antifouling property with maximum FRR of 72.84%. The heavy metal rejection by the membrane was carried out by complexing the metal ions with polyethyleneimine, which exhibited highest rejection of 99.48 and 95.5% of Pb2+and Cd2+, respectively.

Four organic compounds, N1,N4-bis(6-methylpyridin-2-yl)terephthalamide (1), its di-Noxide (3), mono-N-oxide with water (5w) and di-N-oxide (6) of N1,N3-bis(6-methylpyridin-2-yl) (4) have been synthesized and their solid state structures have also been determined using FTIR, NMR, Mass and single crystal X-ray analysis. Three dimensional propagations, conventional and nonconventional hydrogen bonding with their point of interactions, molecular modeling and Hirshfeld surface analysis are discussed in this context.

The title compound, (2 Z )‐5,6‐dimethyl‐2‐[(4‐nitrophenyl) methylidene]‐2,3‐dihydro‐1‐benzo furan‐3‐one, has been synthesized and characterized using experimental (XRD) and theoretical methods (FTIR, NMR, electronic and optical studies). The compound crystallizes in monoclinic space group P 2 1 / c with a = 7.527 (7) Å, b = 15.9397(15) Å, c = 13.5106 (10) Å, β = 117.649 (4)° and Z = 4. The initial coordinate geometry obtained by XRD is further used to obtain the optimized ground state geometry of the title compound using DFT/B3LYP/6-311++G (2d,2p) level of theory. Geometrical parameters, vibration frequencies, Gauge invariant atomic orbital (GIAO) 1 H and 13 C NMR chemical shifts of the title compound have been calculated theoretically using the optimized ground state geometry. Apart from this, density of states of different atoms, band gap studies and optical properties have also been studied successfully using theoretical models. [ABSTRACT FROM AUTHOR]

Nanoparticles are emerging as versatile nanoplatforms for the construction of multifunctional nanoprobes, which not only can deliver drugs into desired tumor regions but also are able to monitor the delivery, release and biodistribution of drugs in real time. In order to assist drug delivery, fluorescent imaging that can make the transportation viewable is often used. Then, various fluorescent nanoprobes that are composed of fluorescent or non-fluorescent nanocarrier, small-molecular fluorophore, drug, targeting ligand are developed and applied in biomedical applications. In this review paper, we will summarize chemical strategies for the construction of multifunctional nanoprobes and for controlled release of drugs. Then, recent examples on fluorescent nanoprobes, which are based on quantum dots, carbon nanodots, upconversion nanoparticles and other nanomaterials, and their applications in optical-guided drug delivery will be reviewed.

C25H18ClFN4O3· C2H6OS, monoclinic, P21(No. 4), a= 6.0486(2) Å, b= 17.4704(7) Å, c= 11.9215(4) Å, β= 96.327(1)°, V= 1252.09(8) Å3, Z= 2, Rgt(F)= 0.0476, wRref(F2)= 0.1004, T= 100 K.

Normal 0 false false false MicrosoftInternetExplorer4 Layered cathode materials are important for Li-ion battery application due to their high theoretical specific capacity. Efforts have been made to synthesize mixed-metal cathode materials such as LiNi1/3Co1/3Mn1/3O2 based materials with promising electrochemical characteristics. This is to lower the expensive Co content and help to stabilize the materials. Substitution of these materials with chromium producing LiNi0.3Co0.3Mn0.3Cr0.1O2 material will also improve the stability of the cathodes. In this work, pure and single phase LiNi0.3Co0.3Mn0.3Cr0.1O2 material was successfully synthesized using a combustion method. The samples were then annealed at 900 °C for 24, 48 and 72 h. From the charge-discharged measurements, it was found that the performance of the LiNi0.3Co0.3Mn0.3Cr0.1O2 cathode material annealed at 900 °C for 24 h shows the best performance. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;}

Two rare new natural products, the neocaged-xanthone pruniflorone T (1) and the rearranged caged-xanthone pruniflorone U (3), and the known caged-xanthone cochinchinone C (2) were isolated from the roots of Cratoxylum formosumssp. pruniflorum. The unique structures of 1–3were determined by analysis of NMR and X-ray diffraction data. The X-ray data of 1–3revealed that they all exist with both enantiomers in their crystal packing. Separation of 1–3by chiral HPLC led to the isolation of three pairs of enantiomers, (−)-1/(+)-1, (−)-2/(+)-2, and (−)-3/(+)-3, and their absolute configurations were determined by analysis of single-crystal X-ray diffraction and ECD spectroscopic data. A 1:1 mixture of 1and 3showed potent in vitro cytotoxicity against an MCF-7 human breast cancer cell line with an IC50value of 0.11 μg/mL.

Phenacyl benzoates possess commercial importance due to their various applications in the fields of synthetic and photochemistry, such as photosensitive blocking groups owing to their ease of cleavage under mild conditions. In the present study, a series of ten new 2-(4-bromophenyl)-2-oxoethyl benzoates 2(a–j), with the general formula Br(C6H4)COCH2OCO(C6H5–nXn), X= Cl, NO2or NH2, and n= 1 or 2, have been synthesized by reacting 4-bromophenacyl bromide with various substituted benzoic acids using potassium carbonate in DMF medium at room temperature. These reactions proceeded with ease under mild conditions producing high purity products in good yield. Each product was characterized by mass spectra, elemental analysis and melting points, its 3D structure was confirmed by single-crystal X-ray diffraction studies. The X-ray 3D structures showed the flexibility of the C(=O)–O–C–C(=O) connecting bridge in which 7 out of 10 compounds tend to form a torsion angle in the range of 70 to 91°, whereas the rest are slightly twisted with a torsion angles of –160, 163, 176 and 178°. Their molecular conformations are in good agreement with another 22 related structures. These synthesized compounds were screened for their abilities for DPPH radical scavenging and ferric reducing anti-oxidant power. The results indicate that these compounds displayed mild anti-oxidant ability when compared to the standard anti-oxidant BHT.

The syntheses, physico-chemical and spectroscopic characterization of ovan-type Schiff-base ligands (L1, L2) and their novel mononuclear Pd(II) complexes (PdL1, PdL2) are reported herein. Elemental analysis, FT-IR, 1H NMR as well as magnetic susceptibility measurements characterised the compounds. The catalytic potential of the Pd(II) complexes for Heck coupling reaction were investigated and monitored using GC. It was observed that both Pd(II) complexes displayed properties of good catalysts for the reaction, indicated by 100% conversion of the starting materials to the subtituted alkene product after 6 hours of reaction time at 100oC in inert conditions. The catalytic activity was compared with the reaction without Pd(II) complexes.

Nanostructures of a new coordination polymer of divalent lead with the ligand 2, 9‐dimethyl‐1, 10‐phenanthroline (dmp) containing the first Pb2‐(μ‐ClO4)2motif, [Pb2(dmp)2(μ‐N3)2(μ‐ClO4)2]n(1), was synthesized by a sonochemical method that produces the coordination polymers at nano size. The new nanostructure was characterized by scanning electron microscopy, X‐ray powder diffraction, IR, 1H NMR and 13C NMR spectroscopy, and elemental analysis. Compound 1was structurally characterized by single‐crystal X‐ray diffraction and the single‐crystal X‐ray data shows that the coordination number of PbIIions is six, (PbN4O2), with two N‐donor atoms from aza‐aromatic base ligands and four O‐donors from two perchlorate anions and two N‐donors from two azide anions. It has a “stereo‐chemically active” electron lone pair, and the coordination sphere is hemidirected. The supramolecular features in these complexes are guided and controlled by weak directional intermolecular interactions. The chains interact with each other through π–π stacking interactions creating a 3D framework. The structure of the title complex was optimized by density functional theory calculations. Calculated structural parameters and IR spectra for the title complex are in agreement with the crystal structure. The PbO nanoparticles were obtained by thermolysis of 1at 180 °C with oleic acid as a surfactant. The average diameter of the nanoparticles was estimated by the Scherrer equation to be 23 nm. The morphology and size of the prepared PbO samples were further observed using SEM.

Two novel 3D lead(II)‐azido and ‐thiocyanato coordination polymers with isonicotinate acid N‐oxide (INO) as the coligand were synthesized and characterized by elemental analysis, IR, and 1H NMR spectroscopy and were also studied using X‐ray crystallography technique. These complexes have the formulas [Pb(INO)(NCS)]n(1) and [Pb(INO)(N3)(H2O)]n(2).

Three series of heteroaryl chalcones, (E)-1-(2-pyridyl)-3-(X)prop-2-en-1-one (Ia-Ic), (E)-1-(2-thienyl)-3-(X)prop-2-en-1-one (IIa-IIc), and (E)-1-(2-furyl)-3-(X)prop-2-en-1-one (IIIa-IIIc), where X = 2,4,5-trimethoxyphenyl (for series a), X = 2,4,6-trimethoxyphenyl (for series b), and X = 3,4,5-trimethoxyphenyl (for series c) were synthesised using basic catalysed aldol condensation and characterised using 1H NMR and FT-IR spectroscopies. Compound IIa was also characterised by single crystal X-ray analysis. The absorption and fluorescence emission spectra of these compounds revealed that the absorption and fluorescence depended on the heterocycle rings and trimethoxysubstituted phenyl rings linked to the enone system. The position of methoxy groups substantially affected the fluorescent properties. Compounds Ia-IIIa containing the 2,4,5-trimethoxyphenyl moiety exhibited the red-shift phenomenon and strong emission fluorescence.

Diorganotin compounds containing tetranuclear tin compositions of the type {[R2Sn(LH)]2O}2in which LH is deprotonated carboxylic acid LHH′ (H′ are the carboxylic and H the phenolic protons of the benzoic acid) HO2C–C6H4‐4‐{N=C(H)C6H3‐2‐OH‐5‐(N=N–C6H4X)} (X = H for L1H, X = 2‐CH3for L2H, X = 3‐CH3for L3H, and X = 4‐CH3for L4H; R = Bu or Oct), were synthesized and characterized by FT‐IR, NMR, and 119Sn Mössbauer spectroscopy. One of the complexes, {[Oct2Sn(O2CC6H4{N=C(H)C6H3‐2‐OH‐5‐(N=NC6H4CH3‐2)})]2O}2was characterized by single‐crystal X‐ray diffaraction, which revealed that the compound is a centrosymmetric tetranuclear bis(dicarboxylatotetrabutyldistannoxane) complex with a planar Sn4O2core. The two μ3‐oxo oyxgen atoms are connected to a Sn2O2ring and to two exocyclic tin atoms. The four carboxylate ligands display two different modes of coordination. Both modes of coordination involve bridging two structurally distinct tin atoms. The solution structures of the complexes were unravelled by 119Sn NMR spectroscopy, and found to be identical to those of the crystalline state.

A new photocyclization strategy by using intermolecular tandem reactions between N‐(ω‐hydroxyalkyl)‐4,5,6,7‐tetrachlorophthalimides (1, 2, and 3) and a series of acyclic and cyclic alkenes is reported. Electron transfer of the triplet‐excited phthalimide with the alkene and regioselective trapping of the alkene cation radical by the hydroxyl group at the phthalimide side chain gives a triplet 1,n‐biradical, which after intersystem crossing (ISC) leads to regio‐ and diastereoselective synthesis of polycyclic heterocycles with an N,O‐containing medium to large ring. Regio‐ and diastereoselectivity in the cyclizations are clarified by unambiguous steric structure assignments of the products by X‐ray diffraction or extensive 2D NMR measurements. The diastereoselectivity is decided by the stereochemical course of the ISC process of the triplet 1,n‐biradicals. These intermolecular photoreactions also furnish a new strategy to generate triplet 1,n‐biradicals. Therefore, in photoreactions of 1and 2with phenylcyclohexene, the unprecedented stereoselective formation of products by intramolecular hydrogen‐atom transfer in the 1,n‐biradical intermediate was found (9and 23). These facts provide direct verification to the reaction pathways of the 1,n‐biradicals and give a new insight into the factors deciding reaction‐pathway partitioning and stereoselectivity.

Three substituted 2,2'-bipyridine adducts of lead(II) thenoyltrifluoroacetonate, [Pb(4,4'-dm-2,2’- bpy)(ttfa)2]2, 1, [Pb(5,5' -dm-2,2’-bpy)(ttfa)2]2, 2, and [Pb(4,4'-dmo-2,2’-bpy)(ttfa)2], 3, (4,4’ -dm- 2,2’-bpy, 5,5’-dm-2,2’-bpy, 4,4’-dmo-2,2’-bpy and ttfa are the abbreviations for 4,4’-dimethyl-, 5,5’-dimethyl-, and 4,4’-dimethoxy-2,2’-bipyridine, and thenoyltrifluoroacetonate, respectively) have been synthesized, characterized by elemental and thermal analysis, IR and 1H- and 13C-NMR spectroscopy, and studied by X-ray crystallography. The supramolecular features in these complexes are guided/controlled by weak directional intermolecular interactions.

C23H30FN5O6, monoclinic, P21/n(no. 14), a= 9.5772(3) Å, b= 15.9466(5) Å, c= 15.8380(5) Å, β= 103.951(1)°, V= 2347.49(13) Å3, Z= 4, Rgt(F)= 0.0423, wR(F2)= 0.192, T= 150 K.

C25H32Cl2F3N5O6, orthorhombic, P212121(no. 19) a= 11.0768(4) Å, b= 15.6620(5) Å, c= 16.6830(5) Å, V= 2894.25(16) Å3, Z= 4, Rgt(F) = 0.0509, wR(F2) = 0.1498, T= 100 K.

C16H19N3O, orthorhombic, Pna21(no. 33), a= 8.0251(7) Å, b= 10.1627(9) Å, c= 17.0686(16) Å, V= 1392.1(2) Å3, Z= 4, Rgt(F)= 0.064, wR(F2) = 0.109, T= 100 K.

A novel 1D PbIIcoordination polymer containing Pb2‐(μ‐N3)2unit [Pb(dmp)(N3)2]n(dmp =  2,9‐dimethyl‐1,10‐phenanthroline) has been prepared and characterized. Single‐crystal X‐ray diffraction analyses show that the coordination number for PbIIions is six, PbN6, with “stereochemically active” electron lone pairs and the coordination sphere being hemidirected. The single‐crystal X‐ray data show the chains interact with each other through the π–π stacking interactions, which create a 3D framework. The structure of title complex has been optimized by density functional theory. Structural parameters and IR spectra for the complex are in agreement with the crystal structure.

Three aza‐aromatic base adducts of cadmium(II) furoyltrifluoroacetonate, [Cd(4,4′‐bpy)(ftfa)2]n(1), [Cd(2,2′‐bpy)(ftfa)2] (2) and [Cd(dmp)(ftfa)2] (3) (“4,4′‐bpy”, “2,2′‐bpy”, “dmp” and “ftfa” are the abbreviations of 4,4′‐bipyridine, 2,2′‐bipyridine, 2,9‐dimethyl‐1,10‐phenanthroline and furoyltrifluoroacetonate, respectively) have been synthesized and characterized by elemental analysis and IR, 1H NMR and 13C NMR spectroscopy and studied by thermal as well as X‐ray crystallography. The single‐crystal structure of these complexes shows that the coordination number of the CdIIions are six with two N‐donor atoms from aza‐aromatic base ligands and four O‐donors from two the furoyltrifluoroacetonates. The supramolecular features in these complexes are guided/controlled by weak directional intermolecular interactions.

Four new cadinane sesquiterpenes ( 1− 4), including a dimeric cadinane derivative ( 2) and a peroxide cadinane analogue ( 3), have been isolated from the leaves of Eupatorium adenophorum. Their structures including absolute configurations were determined on the basis of spectroscopic data interpretation and single-crystal X-ray crystallography. Compound 4showed in vitro cytotoxicity against the HCT-8, Bel-7402, and A2780 cancer cell lines.

To investigate the interactions between noncovalent bond donor and acceptor giving rise to three dimensional networks, compound [Pb(tfpb)2]n(Htfpb = 4,4,4‐trifluoro‐1‐phenyl‐1,3‐butanedione) has been prepared and characterized by elemental analysis, IR, 1H NMR, and 13C NMR spectroscopy and its crystal structure was investigated. The single‐crystal structure of the compound show the coordination number of Pb(II) to be eight with six O‐donor atoms from a “tfpb” ligand and two F‐donors from the anionic ligands. The supramolecular structure of 1is realized by weak directional C–F···F–C and π–π stacking interactions.

A perchloric acid mediated one-step synthesis of lumazine derivatives from pterins and xanthine from guanine is reported. However, 2-pivaloylamino derivatives of pterins underwent simple hydrolysis of the pivaloylamino group generating free pterin compounds, but the 2-oxo derivatives, that is, the lumazine compounds, were not obtained. A novel supramolecular assembly is constructed by the unique hydrogen bonding of H5O2+ bridging two hydrogen-bonded dimers of lumazine to form the co-crystal 21 with aqueous perchloric acid. In contrast, N2-pivaloyl-6-bromo-5-deazapterin was simply hydrolysed to form the protonated deazapterin 22, which forms a unique six-membered cyclic hydrogen-bonded structure leading to the generation of a polymeric supramolecular assembly. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

A 2D lead(II) coordination polymer [Pb2(phen)2(N3)3(ClO4)]n,(1) containing 1,10‐phenanthroline (phen) and two different anions, has been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopy and X‐ray crystallography. The single‐crystal X‐ray data show two different kinds of Pb2+ions with coordination numbers of eight, Pb1 = PbN6O2and Pb2 = PbN8, with hemidirectedand holodirectedstructures, respectively. The supramolecular features in 1is negiotated through the weak but directional C‐H···O and C‐H···N interactions and aromatic π–π stacking interactions.

Abstract: Three new Schiff bases, $$N,N'$$-(bis(pyridin-2-yl)alkylidene)butane-1,4-diamine [(py)(R)C=N-(CH$$_{2}$$)$$_{4}\hbox{-}$$N=C(R)(py), L: py = pyridine; R = H, $$N,N^\prime$$-(bis(pyridin-2-yl)formylidene)butane-1,4-diamine (bpfd); R = Me, $$N,\!N^\prime$$-(bis(pyridin-2-yl)methylidene)butane-1,4-diamine (bpmd); R = C$$_{6}\rm{H}_{5}$$, $$N,N^\prime$$-(bis(pyridin-2-yl)bezylidene)butane-1,4-diamine (bpbd)] were prepared and used to synthesize six dinuclear cadmium(II)azido complexes of type [Cd(L)(N$$_{3}$$)]$$_{2}$$(Y)$$_{2}$$ [L = bpfd, Y = ClO$$_{4}$$ (1a); L = bpfd, Y = PF$$_{6}{^-}$$ (1b); L = bpmd, Y = ClO$$_{4}{^-}$$ (2a); L = bpmd, Y = PF$$_{6}{^-}$$ (2b); L = bpbd, Y = ClO$$_{4}{^-}$$ (3a); and L = bpbd, Y = PF$$_{6}{^-}$$ (3b)]. Two representative members of the series, 3a and 3b, have been characterized by single crystal X-ray diffraction measurements. Structural study reveals that each cadmium center in both dinuclear compounds is located in a distorted octahedral coordination environment surrounded by six nitrogen atoms—four (N1, N2, N3, N4) from tetradentate ligand, and the fifth and sixth positions occupied by nitrogen atoms (N5, N5*) of doubly end-on bridging azides. The complexes display intraligand 1$$(\pi\hbox{--}\pi^{*})$$ fluorescence and intraligand 3$$(\pi\hbox{--}\pi^{*})$$ phosphorescence in glassy solutions (MeOH at 77 K).

Two new second-order nonlinear optical coordination polymers, zinc cadmium tetraselenocyanate ([ZnCd(SeCN)4]n, 1) and cadmium mercury tetraselenocyanate ([CdHg(SeCN)4]n, 2), have been synthesized by reactions of self-assembly. Their structural, optical, and physicochemical properties were characterized by X-ray diffraction, infrared and Raman spectroscopy, electronic spectra, and thermal analyses. Structure analyses reveal that they belong to the tetragonal system I$\bar {4}$ space group. The cell dimensions for 1: a = 11.3420(1), b = 11.3420(1), c = 4.6326(1) Å, V = 595.94(1) Å3, Z = 2, Dc = 3.331 g·cm–3, R1 = 0.0411, wR2 = 0.1058; for 2: a = 11.6579(7), b = 11.6579(7), c = 4.5109(4) Å, V = 613.06(8) Å3, Z = 2, Dc = 3.970 g·cm–3, R1 = 0.0432, wR2 = 0.1031. The structural features of 1 and 2 are Cd–Se=C=N–Zn and Hg–Se=C=N–Cd bridges, respectively, which lead to the formation of an infinite three-dimensional (3D) network. Consistent with their polar structures, compounds 1 and 2 exhibit powder second harmonic generation (SHG) responses much stronger than urea, indicating quite a promising application potential as useful nonlinear optical (NLO) materials. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

A new diferrocenyl-substituted macrocyclic ligand (H2L) and its complexes ML(M = CuII, NiII, ZnII, CdII) were prepared and characterized by IR, elemental analysis, absorption spectra and FAB mass spectra. The ferrocenyl-substituted macrocyclic ligand was characterized by single crystal X-ray diffraction analysis. The superconjugative effect of the cyclopentadienyl (CP) rings increase the activity of the hydrogen atoms in the tetra-azacyclotetradecane macrocyclic ligand. The imine nitrogen atoms lose two protons and coordinate to the metal. The electrochemical properties of these compounds are discussed.

A family of tetradentate ligands, [N,N′-bis(pyridine-2-yl)]ethane-1,2-diamine (L1), [N,N′-bis(pyridine-2-yl)]propane-1,3-diamine (L2) and [N,N′-bis(pyridine-2-yl)]butane-1,4-diamine (L3) has been prepared. These ligands differ only in the number of CH2groups separating two pyridyl/imine moieties, however, in reactions with MnIIand N−3salts, they produce structurally very diverse solids; [Mn2(L1)3(N3)]n(ClO4)3n(1), [Mn2(L2)2(N3)2](PF6)2(2) and [Mn2(L3)(N3)2]n(ClO4)2n(3). Complexes 1, 2and 3consist of azido-bridged magnetically dilute Mn2pairs, arranged as 1-D, discrete and 2-D arrays, respectively. In these materials, the connection between Mn centers within the dinuclear entities occurs through mono-1,3-N−3, bis-1,3-N−3and bis-1,1-N−3bridges, respectively, for 1, 2and 3. Bulk magnetic measurements reveal that the coupling within such units is antiferromagnetic (J= −1.8 cm−1, 1; J= −4.8 cm−1, 2) and ferromagnetic (J= +1.45 cm−1, 3), depending on whether the N−3binding mode is end-to-end (EE) or end-on (EO). The reported values are given according to the convention H= −2JS1S2for the spin-Hamiltonian.

A new Schiff base 4-[N-hydroxyethyl-N-(methyl)amino]benzaldehyde S-methyl dithiocarbazate (HL, where H is a dissociable proton) and the ruthenium complex [Ru(bpy)2L]PF6(bpy = 2,2′-bipyridine) have been synthesized. The structural determinations of the ligand and its ruthenium complex, by X-ray crystallography, show that the ligand is coordinated as a monoanionic bidentate N, S-donor, forming a four-member chelate ring with a bite angle of 65.91°. The complex shows intense MLCT transitions in the visible region. Fluorescent and electrochemical properties have been also studied. The complex in DMF solution exhibited a strong two-photon absorption (t.p.a.) at 532 nm nanosecond laser pulses. The t.p.a. coefficient β, t.p.a. cross-section σ and the third-order optical nonlinearity χ(3)of the complex and the ligand have been determined by the Z-scan technique.

Abstract Two new copper(II) complexes, [Cu2 (Phen)2 (µ2 -OH)2 ((HCO)3) 2 ][Cu2 (Phen) 2 (µ 2 -OH)2 (H2 O)2](dhba)2 .8H2 O (1) and [(bz)4 Cu3 (µ2-OH)2 (ppz)]n(2) (where Phen = 1,10-phenanthroline, dhba = 2,6-dihydroxy-benzoate anion, bz = benzoate anion, and ppz = piperazine), have been synthesized and characterized by elemental analyses, i.r. and single crystal X-ray diffraction. Complex (1) is a tetra-nuclear CuII compound; each CuII atom in the complex has a square-pyramidal geometry, being coordinated by two nitrogen atoms and three oxygen atoms. Complex (2) is a trinuclear CuII compound. The Cu1 atom in the complex has a slightly distorted square plane, being coordinated by four oxygen atoms, while the Cu2 atom has a severely distorted square pyramid geometry, being coordinated by four oxygen atoms and one nitrogen atom. The determination studied by GC/MS analysis indicated that complex (1) has good catalytic activity for the dioxygen oxidization of cyclohexane.

A new Schiff base ligand derived from S-benzyldithiocarbazate and 4-[N-hydroxy ethyl-N-(methyl)amino]benzaldehyde (HL, where H is a dissociable proton) and its NiII, CuII, ZnIIand PdIIcomplexes were prepared and fully characterized. The structures of HL and Ni(L)2were determined by X-ray diffraction analysis, which revealed that the geometry of the NiIIion is square-planar with two equivalent Ni=N and Ni=S bonds, and that the two neighboring molecules in two layers have weak contact. The electronic spectra and solution fluorescence of the ligand and the complexes were studied, and the quantum yields of single-photon fluorescence for the compounds were determined. The compounds possess two-photon absorption (t.p.a.) character and the t.p.a. coefficient βand t.p.a. cross-section σwere determined by the Z-scan technique. Especially, the Zn(L)2complex and the HL ligand exhibit intensive two-photon fluorescence (t.p.f.) at 800 nm laser pulses in the femtosecond regime.

The new binuclear copper(II) complexes Cu2L¹⁻³ and [Cu2L^4,5](ClO4)2 were synthesized by reaction of the monomeric cis-N,N'-bis(3-aminopropyl)oxamidatocopper(II) complex [Cu(oxpn)] with acetylacetone, benzoylacetone, salicylaldehyde, 2-pyridinecarboxaldehyde and diacetyl monoxime in the presence of copper(II) acetate or perchlorate owing to the trans isomerisation of the cis-oxamidato complex. The crystal structure of Cu2L¹ consists of centrosymmetric binuclear copper(II) ions which are bridged by an oxamidato group in the trans conformation with a copper−copper distance of 5.121 Å. Each copper(II) ion occupies an inner site of the N2O2 donor with a distorted square-planar environment. Electrochemical studies showed that two quasireversible one-electron reduction waves are obtained in the cathodic region (E¹pc = −0.48 to −1.02 V, E²pc = −1.08 to −1.34 V). The conproportionation constants Kcon for the mixed-valence Cu^ICu^II complexes have been determined electrochemically. Room-temperature magnetic-moment studies of binuclear copper(II) complexes reveal the presence of a strong antiferromagnetic interaction (μeff = 1.14−1.24 μB) which is also observed from the broad spectra with g = 2.1. A variable-temperature magnetic-susceptibility study of the complexes 1 and 4 gives J values of −510 cm⁻¹ and −497 cm⁻¹ respectively. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Structure and conformation of three tridentate ligands are determined. All these three compounds crystallize in different space groups, the details are as follows: Bis[(3,5-dimethyl,2-hydroxy)-2′-hydroxy-5′-methoxy]benzylcyclohexylamine (DHBC): monoclinic I2/a (a= 17.691(1) Å, b= 9.707(1) Å, c= 24.235(2) Å, β = 91.028(1)°); bis[(3,5-dimethyl,2-hydroxy)-2′-hydroxy-5′-bromo]benzylcyclohexylamine (DHBrBC): tetragonal P41212 (a= b = 12.1138(1) Å, c= 28.485(1) Å) and bis[(3,5-dimethyl,2-hydroxy)-2′-hydroxy-5′-bromo]benzylmethylamine (DHBrBM): triclinic $$P\bar 1$$ (a= 5.228(1), b= 12.364(1) Å, c= 13.234(1) Å, α = 94.04(1)°, β = 95.72(1),° γ = 95.90(1)°). The cyclohexane rings in DHBC and DHBrBC assume chair conformation. Both the phenyl rings are planar in all the molecules and orient at angles of 75.5(1)°, 62.2(1)°, and 53.9(2)°, respectively with each other. The bond angles around N atom show the sp3character. Inter- and intramolecular O–H⋅⋅⋅N and O–H⋅⋅⋅O types of hydrogen bondings stabilize the molecules in the unit cell in addition to van der Waals forces.

The title complex [Mn2(phen)4(FCA)2](ClO4)2·H2O (1)(FCA = dianion of 3-ferrocenyl-2-crotonic acid, phen = 1,10-phenanthroline) has been prepared, and its structure determined by single crystal X-ray diffraction analysis. The structure consists of a dinuclear cation [Mn2(phen)4(FCA)2]2+, non-coordinated perchlorate anions and a water molecule. The two MnIIions are separated by 4.374 Å in the cation and are dicarboxylate-bridged by carboxylate ligands containing ferrocenyl units. Each FCA is bound to two MnIIions through carboxylate oxygens with the syn–antibridging mode. The MnIIion is coordinated in an octahedral N4O2geometry by two chelate phen ligands and two μ-carboxylate oxygen atoms. Electrochemical properties of (1)are discussed.

Three polymeric silver(I) complexes with terephthalate anions as counterions or ligands, [Ag(pren)]2(tp)·2H2O (1), [Ag(en)][Ag(μ2‐tp)]·H2O (2), and [Ag2(μ4‐tp)(apy)2] (3) (where pren = 1, 2‐propylenediamine, tp =terephthalate dianion, en = ethylenediamine, and apy = 2‐aminopyridine) were synthesized and characterized by X‐ray single crystal analysis and infrared spectroscopy. 1crystallizes in the monoclinic space group P211/c with a= 11.3221(5), b= 7.1522(3), c= 14.8128(5)Å, V = 1015.77(7)Å3, β= 122.132(2), and Z= 2. 2crystallizes in the orthorhombic space group Pnmawith a= 9.6144(6), b= 11.3465(7), c= 11.4810(7)Å, V = 1252.5(1)Å3, and Z= 4. 3crystallizes in the monoclinic space group P21/nwith a= 8.2003(5), b= 5.8869(4), c= 18.3769(11)Å, β= 92.593(1), V = 886.2(1)Å3, and Z= 4. Terephthalate dianions are not coordinated to the metal atoms in 1, but act as a μ2‐bridging ligand in 2and as a μ4‐bridging ligand in 3.

Three new ligands, N-(8-quinolyl)pyridine-2-carboxamide (HL1), N-(8-quinolyl)glycine-N′-Boc-carboxamide (HL2), N-(8-quinolyl)-L-alanine-N′-Boc-carboxamide (HL3), and their Cu(II) complexes have been synthesized. Crystallographic data reveal that complex I, [Cu(L1)(Ac)(H2O)], is penta-coordinated with a square-pyramidal geometry while complexes V [Cu(L2′)(H2O)] and VI [Cu(L3′)(H2O)] are tetra-coordinated to give square planar geometry. In vitrotests showed that the Cu(II) complexes with L1(I-IV) exhibited cytotoxicity at a concentration of 10−8M against murine leukemia P-388 and human leukemia HL-60 cell lines, which is more potent than cisplatin. However, ligands HL2and HL3and their corresponding copper complexes demonstrated very weak in vitroactivities towards the cell lines examined. ESMS data shows that complex I binds rapidly with 5′-GMP to form 1:1 and 2:2 adduct.

Two coordination polymers [Zn(Cabo)2(EtOH)2(4,4′-Bipy)]n(1), and [Zn2(Cabo)2(NO3)2(4,4′-Bipy)2]n(2)(Cabo = carbazolylacetate, 4,4′-Bipy = 4,4′-bipyridine) with chain and ladder structures, respectively, were prepared and characterized by X-ray single-crystal structural analysis. The results showed that the different anions of metal salts have a large effect on the construction of coordination frameworks. Both complexes show strong emissions in the solid state as well as high thermal stability.