H<sub>5</sub>IO<sub>6</sub>/KI: A New Combination Reagent for Iodination of Aromatic Amines, and Trimethylsilylation of Alcohols and Phenols through<i>in situ</i>Generation of Iodine under Mild Conditions
作者:Mohammad Ali Zolfigol、Ardeshir Khazaei、Eskandar Kolvari、Nadiya Koukabi、Hamid Soltani、Maryam Behjunia
DOI:10.1002/hlca.200900259
日期:2010.3
A simple method for the in situ generation of iodine using H5IO6/KI has been developed, and its application in silylation of OH group and iodination of aromatic amines is described.
A practical and highly efficientsilylation of alcohol and phenol derivatives with hexamethyldisilazane (HMDS) using acidic ionic liquids undermild reaction conditions is described. A series of Brønsted as well as Brønsted–Lewis acidic ionic liquids were prepared and their performance investigated for the silylation of a wide variety of alcohols and phenols with HMDS. Imidazole‐ as well as N‐meth
at room temperature. While, under the same reaction conditions [Sn IV (TPP)Cl 2 ] is less efficient to catalyze these reactions. One important feature of this catalyst is its ability in the chemoselective silylation of primary alcohols in the presence of secondary and tertiaryalcohols and phenols. The catalyst was reused several times without loss of its catalytic activity.
Synthesis and characterization of a bifunctional nanomagnetic solid acid catalyst (Fe<sub>3</sub>
O<sub>4</sub>
@CeO<sub>2</sub>
/SO<sub>4</sub>
<sup>2−</sup>
) and investigation of its efficiency in the protection process of alcohols and phenols via hexamethyldisilazane under solvent-free conditions
synthesized using the coprecipitation method and functionalized by an ammonium sulfate solution to achieve a heterogeneous solid acid Fe3O4@CeO2/SO42− (FCA) catalyst. The synthesized bifunctional catalyst was used in the protection process of alcohols and phenols using hexamethyldisilazane (HMDS) at ambient temperature undersolvent‐free conditions. Due to its excellent magnetic properties, FCA can easily be
在这项研究中,使用共沉淀法合成了Fe 3 O 4 @CeO 2(FC),并通过硫酸铵溶液对其进行了功能化处理,从而获得了非均相的固体酸Fe 3 O 4 @CeO 2 / SO 4 2-(FCA)催化剂。合成的双功能催化剂在环境温度和无溶剂条件下使用六甲基二硅氮烷(HMDS)用于醇和酚的保护过程。由于其优异的磁性,FCA可以很容易地从反应混合物中分离出来并重复使用几次,而不会显着降低其催化活性。纳米催化剂的优异的收率和选择性,简单的分离,低成本和高可回收性是该方法的突出优点。使用不同技术进行表征,例如傅立叶变换红外光谱(FT-IR),扫描电子显微镜(SEM),能量色散X射线光谱(EDX),X射线衍射(XRD)和振动样品磁强计( VSM)。
Highly efficient and selective trimethylsilylation of alcohols and phenols with hexamethyldisilazane catalyzed by polystyrene-bound tin(IV) porphyrin
[Sn IV (TNH 2 PP)(OTf) 2 ], supported on chloromethylated polystyrene in the trimethylsilylation of alcohols and phenols with hexamethyldisilazane is reported. The prepared catalyst was characterized by elemental analysis, FT-IR and diffuses reflectance UV–Vis spectroscopic methods. This catalyst was used for selective trimethylsilylation of different alcohols and phenols with HMDS, with short reaction