A Novel Green Synthesis of Quinolines through Acid-catalyzed Friedlander Reaction in Ionic Liquids

Quinoline derivatives were efficiently prepared through acid-catalyzed Friedlander reaction in ionic liquid ([bmim] [BF4]). It is shown that the proposed method is operationally simple and environmentally benign in that the reaction media and the catalyst can be recovered and be reused effectively for at least four times.     

A new approach to the synthesis of α-chlorocycloalkanones

α-Chlorocycloalkanones(Ⅳ) were synthesized from cycloalkanones via potassiumα-oxocycloalkylsulfonates(Ⅱ).A two-step mechanism was proposed to explain the formation ofⅣfromⅡ.     

KF/Al~2O~3/PEG 4000(FAP)存在下氯仿的Michael加成反应

在KF/Al~2O~3/PEG4000(FAP)存在下,氯仿可与α,β-不饱和羰基化合物进行Michael加成反应,得到中等产率的三氯甲基化合物。     

Organic Reactions in Ionic Liquids： An Efficient Method for the Synthesis of Phenacyl Esters by Reaction of Carboxylic Acids with α-Bromoacetophenone Promoted by Potassium Fluoride

An efficient method is reported for the synthesis of phenacyl esters by reaction of carboxylic acids with a-bromoacetophenone promoted by potassium fluoride in ionic liquid [Bmim]PF6, the yield of the reaction is almost quantitative and the products are essentially pure.     

Influence of the Size of Aromatic Chelate Ligands on the Structures of Cadmium(II) Tetracarboxylates Polymers: From 2D Layered Network to 3D Metal‐Organic Framework

To determine the influence of the size of the aromatic chelate ligands on the frameworks of metal tretracarboxylate polymers, two new coordination polymers [Cd(btc)_0.5 (2,2′‐bpy)] ( 1 ) and [Cd(btc)_0.5(phen)]·H₂O ( 2 ) (H₄btc = biphenyl‐3,3′,4,4′‐tetracarboxylic acid, 2,2′‐bpy = 2,2′‐bipyridine, phen = 1,10‐phenanthroline) have been synthesized under similar hydrothermal conditions. In complex 1 , the dimeric Cd₂ units are linked by bridging btc^4? ligand to form a 2D layered network, whereas complex 2 possesses a 3D metal‐organic framework consisting of the dimeric Cd₂ units. The differences of two metal‐organic frameworks demonstrate that the size of the rigid aromatic chelate ligands have an important effect on the structures of their complexes. Additionally, the two complexes show strong fluorescence in the solid state at room temperature.     

A New Cyclohexene Oxide from Uvaria tonkinensis var. subglabra

A new compound, subglain B, was isolated from the stems of Uvaria tonkinensis var.subglabra and its structure was identified as 1S, 2R, 3S, 6R-1-benzoyloxymethylene-1,2-dihydroxy-3-benzoyloxy-6-chlorocyclohex-4-ene (1), by spectral evidences.     

甘氨酸与氯化碱金属在水中的焓相互作用参数

氨基酸在混合溶液中的热力学性质及相互作用的研究不论对溶液化学还是生命科学都是十分重要的．对此国内已有不少的研究h，’1．利用偿效应的方法研究氨基酸与电解质间的相互作用是很有效的卜一句，但大多数的工作都是在低浓度下研究一个氨基酸分子和一个电解质离子对间的相互作用烩．本文测定了甘氨酸在水中和在LICI、NaCI、KCI的水溶液中的溶解偿，计算出甘氨酸与各个公在水中的偿对相互作用参数和三相互作用参数，并由此讨论了甘氨酸与这些盐的对分子相互作用和三分子相互作用．1实验部分试剂：甘氨酸为ARfa，K甲醇一水重结晶．LI…     

Oligodeoxyribonucleotide analogues with bridging dimethylene sulfide,sulfoxide, and sulfone groups. Toward a second-generation model of nucleic acid structure

Short DNA analogues with bridging dimethylene sulfide, sulfoxide, and sulfone groups replacing the phosphate diesters (S-DNAs) were synthesized from building blocks prepared via two routes, both starting from D-glucose. Building blocks for RNA analogues were prepared by stereoselective introduction of nucleobase into a 2'-acylated ribose analogue. The ribose analogues were converted to deoxyribose analogues by replacement of a 3'-OH group by a thioacetyl unit, followed by photolytic deoxygenation or radical-based 2'-deoxygenation. DNA analogues joined via CH(2)(-)S-CH(2) units were prepared by S(N)2 displacement of a 6'-mesyl group on one building block using a thiolate nucleophile of another. 4,4'-Dimethoxytrityl protection and deprotection schemes were established for both the thiol and hydroxyl groups. The corresponding sulfoxide DNA analogues were obtained by oxidation with hydrogen peroxide. Sulfone DNA analogues were obtained by oxidation of the sulfide DNA with persulfate or hydrogen peroxide in the presence of a titanium silicate catalyst. The physical properties of several representative oligonucleotide analogues were examined, and interpreted in light of a "second-generation" model for DNA strand-strand recognition, a model that emphasizes the role of the polyanionic backbone in diminishing unwanted tendencies of highly functionalized molecules to form "structure" in solution. Even short sulfide-linked DNA analogues displayed association properties different from those displayed by standard DNA molecules. Complex formation observed with sulfide-linked tetramers by HPLC study in different solvents suggested that the complex is formed using hydrogen bonding. Sulfone-linked dinucleotides display Watson-Crick behavior; the tetramer, however, displayed self-structure. Self-structure and self-aggregation become more prominent as the length of the oligonucleotide analogues increases. The tendency to self-aggregate can be decreased by adding a charged sulfonate group to the 3'-end of the DNA analogue. Features of the second-generation model are important for many areas of nucleic acid chemistry, from the design of nucleic acid therapeutic agents to the search for life on other planets.     

Macro-, Micro-, Nano- and Crystal Structures of a Homodinuclear Complex [NH3（ CH2）3NH3]2{Na2[（C6H4O2）2]（C6H4O2H）2}

A homodinuclear complex （NH3CH2CH2CH2NH3）2 {Na2[（C6H4O2）2] （C6H4O2H）2} （1） has been synthesized by a solution-based self-assembly route. It crystallized in monoclinic system with space group P21/c. Every sodium ion coordinates in a tetragonal prism fashion with two O atoms of a terminal chelating catecholate ligand and three O atoms from two bridging catecholate ligands. Two neighboring NaO5 tetragonal prisms are edge-shared and centrosymmetric with regard to the inversion center to form a binuclear cluster {Na2[（C6H4O2）2]（C6H4OOH）2}^4- anion. The complex anions were aligned parallelly by n-n interaction and linked with the protonated 1,3-propylenediamine through hydrogen bonds which were assembled into a multi-lamellar structure with channels. The crystal exhibits rectangular geometry with an interior triangle hollow structure under optical microscopy. And the scanning electron microscopy （SEM） indicates that the wall of the tubes shows multi-lamella morphologies. Further, the transmission electron microscopy （TEM） reveals that the crystal is composed of multi-lamellar nano-tubes with diameters less than 100 nm. The molecular structure of the complex was compared with that of its isomer complex 2.     

[{Cu(phen)2}(μ‐malato){Cu(phen)(NO3)}](NO3)·4H2O: malate acting as a tetra­dentate and dibridging ligand in a dinuclear copper complex

The crystal structure of the title compound, μ‐2‐hydroxy­butane­dioato‐1κ²O⁴,O^4′:2κ³O¹,O²,O⁴‐nitrato‐2κO‐tris­(1,10‐phen­anthroline)‐1κ⁴N,N′;2κ²N,N′‐dicopper(II) nitrate tetra­hydrate, [Cu₂(C₄H₃O₅)(NO₃)(C₁₂H₈N₂)₃](NO₃)·4H₂O, contains an unsymmetrical dinuclear copper complex with Cu(phen)₂ and Cu(phen)(NO₃) moieties (phen is 1,10‐phenanthroline) bridged by a malate (2‐hydroxy­butane­dioate) ligand, which acts as a double‐bridging and tetra­dentate ligand. As a result of this double‐bridging action, especially the direct coordination of the O atom of one carboxyl­ate group of malate to the two Cu atoms, the Cu⋯Cu distance is only 4.199 (1) Å and the two phen planes are roughly parallel [the shortest inter­planar distance is 3.28 (1) Å], exhibiting an obvious intra­molecular π–π stacking inter­action.