RHA / TiO 2纳米复合材料的制备和表征:引入有效且可重复使用的催化剂,用于化学选择性的三甲基甲硅烷基保护和醇和酚的脱保护
摘要:
在这项工作中,稻壳灰(RHA)作为无定形二氧化硅的天然来源,被用作合成RHA / TiO 2纳米复合材料的锐钛矿相二氧化钛纳米粒子的载体。该纳米复合材料用作各种醇和酚的化学选择性三甲基甲硅烷基化和所得三甲基甲硅烷基醚的脱保护的有效催化剂。该程序在非常短的反应时间内以优异的产率获得了产物。同样,该催化剂可以重复使用至少六次,而不会损失其催化活性。
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.
Nano Fe<sub>3</sub>O<sub>4</sub>@ZrO<sub>2</sub>/SO<sub>4</sub><sup>2−</sup>: A highly efficient catalyst for the protection and deprotection of hydroxyl groups using HMDS under solvent-free condition
the protection and deprotection process of various types of alcohols and phenols by HMDS in the presence of nano magnetic sulfated zirconia (Fe3O4@ZrO2/SO42−) as a solid acidcatalyst under very mild and solvent-free condition. This method has interesting advantages like short reaction times and a simple workup process. With regard to some outstanding benefits of this new heterogeneous catalyst such
[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
Highly efficient and chemoselective trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) catalyzed by reusable electron-deficient [TiIV(salophen)(OTf)2]
highly efficient trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) catalyzed by high-valent [TiIV(salophen)(OTf)2] is reported. Under these conditions, primary, secondary and tertiaryalcohols as well as phenols were silylated in short reaction times and high yields. It is noteworthy that this method can be used for chemoselective silylation of primary alcohols in the presence
Graphene oxide-bound electron-deficient tin(IV) porphyrin: a highly efficient and selective catalyst for trimethylsilylation of alcohols and phenols with hexamethyldisilazane
trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) is reported. The prepared catalyst was characterized using inductively coupled plasma analysis, scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared and diffuse reflectance UV–visible spectroscopies. This heterogeneous catalyst was used for selective trimethylsilylation of various alcohols