Effect of fluorine-containing chiral templates on Mg distribution in the structure of MgAPO-5 and its influence on catalytic activity

Abstract

MgAPO-5 materials have been synthesized by using three new structure directing agents: S-(−)-1-benzyl-2-pyrrolidinemethanol, and its ortho- and meta-fluoro-benzyl derivatives. Their acidity has been measured and their catalytic activity tested in the cyclohexene oxide opening acid-catalyzed reaction. The catalytic activity of these materials can be related to their acidity. It has been found that MgAPO-5 samples synthesized from both fluorinated structure directing agents are much more active as acid catalysts for the reaction. A computational study based on molecular mechanics shows a rigid arrangement of the organic molecules in form of helices of dimers within the AFI structure, and suggests a direction of the fluorinated molecules towards the incorporation of magnesium atoms in the framework.