Theoretical Study of the C-Cl Bond Dissociation Enthalpy and Electronic Structure of Substituted Chlorobenzene Compounds

利用密度泛函(DFT)三种交换/相关函数(B3LYP, B3PW91,B3P86)结合6-31G**和6-311G**基组,计算了13个取代氯苯化合物的键离解能. 结果表明B3P86/6-311G**方法是计算取代氯苯化合物键离解能的可信方法,研究发现C-Cl键的键离解能与所使用的基组和计算方法密切相关,取代基对C-Cl键的键离解能的影响不明显. 研究了目标化合物的前线轨道能级差,并对取代氯苯化合物的热稳定性做了评估.     

Synthesis and characterization of f-element iodate architectures with variable dimensionality, alpha- and beta-Am(IO3)3

Two americium(III) iodates, beta-Am(IO3)3 (I) and alpha-Am(IO3)3 (II), have been prepared from the aqueous reactions of Am(III) with KIO(4) at 180 degrees C and have been characterized by single-crystal X-ray diffraction, diffuse reflectance, and Raman spectroscopy. The alpha-form is consistent with the known structure type I of anhydrous lanthanide iodates. It consists of a three-dimensional network of pyramidal iodate groups bridging [AmO8] polyhedra where each of the americium ions are coordinated to eight iodate ligands. The beta-form reveals a novel architecture that is unknown within the f-element iodate series. beta-Am(IO3)3 exhibits a two-dimensional layered structure with nine-coordinate Am(III) atoms. Three crystallographically unique pyramidal iodate anions link the Am atoms into corrugated sheets that interact with one another through intermolecular IO3-...IO3- interactions forming dimeric I2O10 units. One of these anions utilizes all three O atoms to simultaneously bridge three Am atoms. The other two iodate ligands bridge only two Am atoms and have one terminal O atom. In contrast to alpha-Am(IO3)3, where the [IO3] ligands are solely corner-sharing with [AmO8] polyhedra, a complex arrangement of corner- and edge-sharing mu2- and mu3-[IO3] pyramids can be found in beta-Am(IO3)3. Crystallographic data: I, monoclinic, space group P2(1)/n, a = 8.871(3) A, b = 5.933(2) A, c = 15.315(4) A, beta = 96.948(4) degrees , V = 800.1(4) A(3), Z = 4; II, monoclinic, space group P2(1)/c, a = 7.243(2) A, b = 8.538(3) A, c = 13.513(5) A, beta = 100.123(6) degrees , V = 822.7(5) A(3), Z = 4.     

From Zn-Al layered double hydroxide to ZnO nanostructure:Gradually etching by sodium hydroxide

Zn-Al layered double hydroxide(LDH) was used as precursor to produce ZnO nanostructures through dissolution of aluminum hydroxide in caustic soda.The Zn-Al LDH could transform into different nanostructures of ZnO on LDH nanosheets and even pure ZnO nanorods under various NaOH concentration.The formed ZnO nanorods vertically aligned on both LDH sides.UV-vis diverse reflectance spectra show that the obtained ZnO nanorods have a band gap of approximately 3.05 eV.Such ZnO/LDH nanostructures might be used as photocatalyst in the organic pollutant decomposition.     

Asymmetric transfer hydrogenation of ketones catalyzed by nickel complex with new PNO-type ligands

The new polydentate mixed-N,P,O chiral ligands have been synthesized by the condensation of bis（o-formylphenyl）- phenylphosphane and R-phenylglycinol in CHCl₃,and fully characterized by IR,NMR and EIMS spectra.These ligands were employed with a simple Ni complex Ni（PPh_s）₂Cl₂ in situ as catalytic systems for asymmetric transfer hydrogenation of ketones,and the corresponding optical alcohols were obtained with up to 84%ee under mild conditions.     

Concise synthesis of (-)-anisomycin

The antibiotic (-)-anisomycin was synthesized starting from D-tyrosine using Sharpless asymmetric epoxidation as a key reaction followed by formation and hydrolysis of oxazoline set up all chiral center.     

A highly selective solid-contact electrode for Ag~+ based on a monoazathiacrown ether ionophore

A new solid-contact Ag⁺-selective electrode was prepared with 9,10,12,13,24,25-hexahydro-5H,15H,23H-dibenzo [b,q][1,7,10,13,19,4,16]-entathiadiazacyclodocosine-6,16（7H,17H）-dione as ionophore,and cc,a>-dihexylsexithiophene（DH- 6T） ion-to-electron transducer.The sensor exhibited a working concentration range of 10⁸ to 10^-3 mol/L,with a near-Nernstian slope of 55.1±0.2 mV/dec and detection limit of 1.7×10^-9 mol/L.The fabricated electrodes demonstrated excellent selectivity over the most common monovalent and divalent cations.     

*-Regular Leavitt path algebras of arbitrary graphs

If K is a field with involution and E an arbitrary graph, the involution from K naturally induces an involution of the Leavitt path algebra L _K (E). We show that the involution on L _K (E) is proper if the involution on K is positive-definite, even in the case when the graph E is not necessarily finite or row-finite. It has been shown that the Leavitt path algebra L _K (E) is regular if and only if E is acyclic. We give necessary and sufficient conditions for L _K (E) to be *-regular (i.e., regular with proper involution). This characterization of *-regularity of a Leavitt path algebra is given in terms of an algebraic property of K, not just a graph-theoretic property of E. This differs from the known characterizations of various other algebraic properties of a Leavitt path algebra in terms of graphtheoretic properties of E alone. As a corollary, we show that Handelman’s conjecture (stating that every *-regular ring is unit-regular) holds for Leavitt path algebras. Moreover, its generalized version for rings with local units also continues to hold for Leavitt path algebras over arbitrary graphs.     

Synthesis and Crystal Structure of a New Tetracopper Complex [Cu(H_2O)_3Cu(HCDTA)]_2(ClO_4)_2·H_2O

A new tetracopper complex [Cu(H2O)3Cu(HCDTA)]2(ClO4)2·H2O (CDTA = transcyclohexane-1,2-diamine-N,N,N′,N′-tetraacetate) has been prepared and characterized by singlecrystal X-ray diffraction analysis. The crystal adopts space group C2/c with a = 16.990(10), b = 9.150(5), c = 29.318(17) , β = 104.289(9)°, V = 4417(4) 3, Z = 4, C28H52Cl2Cu4N4O31, Mr = 1265.80, Dc = 1.904 g/cm3, μ = 2.130 mm-1, F(000) = 2584, T = 293(2) K, the final R = 0.0328 and wR = 0.0809 for 4938 observed reflections (I 2σ(I)). The tetracopper units are interconnected by weak covalent bonds into a layered structure.     

Zn(II)-phthalocyanines as phototherapeutic agents for cutaneous diseases. Photosensitization of fibroblasts and keratinocytes

Two tetrasubstituted (RLP024 and RLP040) and one monosubstituted (MRLP101) Zn-phthalocyanines were readily accumulated by three skin-derived cell lines (HT-1080 transformed human fibroblasts, 3T3 mouse embryo fibroblasts and HaCaT human keratinocytes) upon 1 h-incubation with 0.5-5 microM phthalocyanine concentrations. The affinity was markedly larger for the tetra- as compared with the mono-substituted phthalocyanine, even though smaller phthalocyanine amounts were generally recovered from keratinocytes. As a consequence, the two tetra-substituted phthalocyanines exhibited a higher phototoxicity against all the three cell lines. Typically, the cell survival decreased by at least 80% after 1 min irradiation with 600-700 nm light at a fluence-rate of 50 mW/cm2 in the presence of 5 microM phthalocyanine. Fluorescence microscopy and caspase-3 activation studies indicate that cell death of fibroblasts largely occurred by a random-necrotic process while the keratinocytes underwent cell death predominantly via apoptosis in spite of a very similar pattern of subcellular distribution of the phthalocyanines.     

Endomorphin analogues with balanced affinity for bothμ- andδ-opioid receptors

Analogues of endomorphin and tripeptidcs modified at positions 4 and 3,respectively,with various phenylalanine analogues were synthesized and their affinities for opioid receptors were evaluated.Most of the peptides exhibited potentμ-receptor affinity and selectivity,among them,compound 7(Dmt-Pro-Tmp-Tmp-NH_2) exhibited potent affinity for bothμ-andδ-receptors (K_iμ= 0.47 nmol/L,K_iδ= 1.63 nmol/L).