Iodine-mediated one-pot synthesis of C-3 acylated indolizines from pyridines,aryl methyl ketones and acrylate derivatives

An I₂/CuI-promoted multi-component reaction from pyridines, aryl methyl ketones and electron deficient acrylates has been accomplished in a “one-pot” manner, which provides a straightforward and efficient access to C-3 acylated indolizines. The key intermediate of N-ylides is hypothesized to be generated in situ from pyridines and (hetero)aryl methyl ketones in the presence of iodine. This method has been applied in the synthesis of two molecules with anticonvulsant and anti-inflammatory activities.     

Iodine/MeOH: a novel and efficient reagent system for thiocyanation of aromatics and heteroaromatics

Indoles, pyrroles, oxindoles and aromatic amino compounds undergo smooth thiocyanation with ammonium thiocyanate in the presence of molecular iodine in methanol under mild conditions to afford the corresponding 3-indolyl, 2-pyrrolyl and 4-aryl thiocyanates, respectively, in excellent yields with high selectivity. The reactions proceed rapidly at room temperature without heating or the use of strong Lewis acids.     

酚醛树脂热裂解产物的导电特性

近年来,无论是从理论方面还是从实验方面,人们对导电高分子材料的研究都不断深入,最近报道掺杂的聚乙炔电导率已高达10~5S·cm~(-1),但聚乙炔在空气中不稳定,应用受到限制。 一维石墨由于具有缩合芳香环结构,在空气中表现出很高的稳定性,日本K.Tanaka等人对一维石墨成员从理论上进行了详细讨论,认为具有多并苯骨架结构的一维石墨成员     

提高碘的ICP－AES测定灵敏度的一种进样方法

研究了一种进样方法：让氧化剂和含碘试样溶液从两路进入反应器混合，生成碘进入雾化室雾化，以碘分子气体形式进入等离子体光源，可使检出限降低两个数量级，由１９２．５μｇ／ｍＬ降到０．８５μｇ／ｍＬ。     

Zero-field current-voltage characteristics in high-temperature superconductors

We have observed the anomalous magnetization of Bi₂Sr₂CaCu_2−xNi_xO₈ (x = 0 and 0.02) single crystals. Anisotropy decreases with iodine intercalation although it expands the space between CuO₂ layers. Iodine intercalation seems to suppress the magnetization anomaly for Ni = 1% crystals, but not for Ni = 1% substituted crystals. We have discussed these results in terms of the increase of anisotropy by Ni substitution and the dimensional crossover of flux lines. Effects of both oxygen concentration and substitution of a magnetic element for the Cu site on the anisotropy of Bi₂Sr₂CaCu₂O₈ crystals show the same tendency as the case of the YBa₂Cu₃O₇ superconductor.     

石墨炉T1I分子吸收光谱法测定地质样品中痕量碘

提出以五氧化二钒和 混合助融剂高温热解地质样品，平台石墨炉Ｔ１Ｉ分子吸收光谱法测定地质样品右痕量碘。方法简便，可靠，标准物质测定结果与推荐值吻合。     

水相中可见光下苯甲醇氧化合成喹唑啉酮衍生物的研究

通过在水相中可见光下2-氨基苯甲酰胺与苄醇氧化制备喹唑啉酮的环化反应,应用廉价易得、操作简单的单质碘作为光催化剂,在室温下反应获得较好收率的产物.目标产物的最高产率可达92%,为喹唑啉酮类化合物的合成提供了一种绿色经济的方法.运用此策略合成的N-(2-氟-5-甲基苯基)-6-(2,2,2-三氟乙氧基)蝶啶-4-胺对肿瘤细胞具有明显的抑制活性.     

Influence of zirconium doping on the activities of zirconium and iodine co-doped titanium dioxide in the decolorization of methyl orange under visible light irradiation

Zirconium and iodine co-doped titanium dioxide (Zr-I-TiO₂) was prepared by the hydrolysis of tetrabutyl titanate, premixed with zirconium nitrate in an iodic acid aqueous solution, followed by calcination in air. The structure and properties of the resultant catalyst powders were characterized by X-ray diffraction, the Brunauer-Emmett-Teller method, X-ray photoelectron spectroscopy, transmission electron microscopy, and UV-vis absorption spectroscopy. The catalytic activity of the catalyst was evaluated by monitoring the photocatalytic decolorization of methyl orange under visible light irradiation. The results showed that the activities of Zr-I-TiO₂ catalysts were higher than that of TiO₂ doped with iodine alone (I-TiO₂), and the optimal doping concentration in the Zr-I-TiO₂ calcined at 400 °C was determined to be about 0.05 (molar ratio of Zr:Ti). In addition, the photocatalytic activity of Zr-I-TiO₂ calcined at 400 °C was found to be significantly higher than that calcined at 500 or 600 °C. Based on the physico-chemical characterization, we concluded that the role of zirconium on the I-TiO₂ surface is to increase the number of reactive sites by generating a small crystal size and large surface area. The inhibition of electron-hole pair recombination, by trapping photo-generated electrons with Zr⁴⁺, did not contribute markedly to the improved photocatalytic activity of Zr-I-TiO₂.     

Iodine Promoted Glycosylation with Glycosyl Iodides: α‐Glycoside Synthesis

Glycosidation of fully acetylated glucopyranosyl iodide with methanol under the influence of iodine gave α‐glucoside selectively. Use of less reactive acceptors led to the formation of α/β‐mixtures. Glycosylations with fully benzoylated glucosyl iodide yielded β‐glucosides only. In contrast, iodine-promoted glycosylation of serine and threonine with 2‐azido‐2‐deoxy‐glycosyl iodides, easily obtained in three steps, proceeded smoothly, resulting in only α‐linked products in high yield in most cases.     

I2-mediated C3-formylation of indoles by tertiary amine and H2O

An I₂-promoted 3-formylation of free (N–H) and N-substituted indoles with tetramethylethylenediamine (TMEDA) and H₂O as the carbonyl source is achieved, providing 3-formylindole in moderate to excellent yields with good functional group tolerance. This procedure represents an exceedingly attractive alternative to the traditional formylation methods.