Rapid synthesis of alkylaminophenols via the Petasis borono–Mannich reaction using protonated trititanate nanotubes as robust solid–acid catalysts
作者:Bhoomireddy Rajendra Prasad Reddy、Peddiahgari Vasu Govardhana Reddy、Dharani Praveen Kumar、Bijivemula N. Reddy、Muthukonda V. Shankar
DOI:10.1039/c5ra25064a
日期:——
nanotubes was ascribed to a sufficient amount of hydroxy groups and high concentration of Brønsted and Lewis acid sites on the tubular surface, which are essential for adsorption and catalytic reactions. The recyclability of H2Ti3O7 catalyst is another emphasis for the proposed methodology. For the first time, we reported novel alkylaminophenols bearing 2-(pyrimidin-2-yl)-2,5-diazabicyclo[2.2.1]-heptane.
使用一锅三组分的Petasis borono-Mannich(PBM)反应,使用质子化的三钛酸(H 2 Ti 3 O 7)纳米管作为非均相固体酸催化剂,可以快速有效地合成烷基氨基酚。与以前的报告相比,人们探索了具有各种形态的Ti-O基材料,例如细颗粒,纳米球,纳米棒和管,它们在PBM反应中的催化活性。XRD图谱显示了纳米管和纳米棒的层状三钛酸酯结构。分别为细颗粒和纳米球的锐钛矿和双相锐钛矿-金红石结构。表面积分析和NH 3-TPD吸附结果证实存在于H 2 Ti 3 O 7纳米管中的表面积更大,且Brønsted和Lewis酸位高。按照以下顺序观察到PBM反应的催化效率:H 2 Ti 3 O 7纳米管> H 2 Ti 3 O 7纳米棒> TiO 2纳米球> TiO 2细颗粒。H 2 Ti 3 O 7的出色催化性能碳纳米管归因于足够数量的羟基以及管状表面上高浓度的布朗斯台德和路易斯酸位,这对于吸附和催化反应至关重要。H