Acetalization of Carbonyl Compounds with Pentaerythritol Catalyzed by Metal(IV) Phosphates as Solid Acid Catalysts

Abstract

In the present endeavor, amorphous cerium phosphate (CP) and thorium phosphate (TP) have been synthesized by the sol–gel method. Further, CP and TP also have been synthesized under microwave irradiation to yield CPM and TPM. The materials have been characterized for elemental analysis (inductively coupled plasma-atomic emission spectrometry, ICP-AES), spectral analysis (Fourier transform infrared spectroscopy, FTIR), thermal analysis (TGA), X-ray diffraction studies, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, Brunauer–Emmett–Teller (BET) surface area analysis, and surface acidity (NH3-temperature programmed desorption (TPD)). Chemical stability of the materials in various acids, bases, and organic solvent media has been studied, and their potential use as solid acid catalysts has been explored by studying acetal formation. A simple, efficient, and highly eco-friendly protocol is described for the acetalization of benzaldehyde, cyclohexanone, acetophenone and benzophenone with pentaerythritol by varying parameters such as reaction time, catalyst amount, and mole ratio of the reactants. The catalytic activity of CP, TP, CPM, and TPM has been compared and correlated with surface properties of the materials.

A novel solid acid catalyst synthesized from ZnAl2O4 spinel and its application in the esterification of acetic acid and n-butyl alcohol

“…23,24 The suction-induced complex S]O improves the electron-accepting ability of the metal atoms, contributing to the formation of supper acid. 27 Thus, 1.55 wt% is sufficient for the esterication reaction. The surface sulphur content is 5.97% (atomic ratio), which is the quantitative estimated by means of XPS.…”

ab initio Method on the Mechanism of Acetalization of 2-Methoxybenzaldehyde Using Halogen Acid Catalysts

“…The formation of hemiacetal also named as halfway processing to form acetals. The second step produced acetal by reaction of hemiacetal with second alcohol molecule followed with protonation of hemiacetal by an acid catalyst, removal of water, nucleophilic attack by a methanol and the last was the loss of water to form acetal product [2,15,16]. Yusuf et al [16,17] reported the reaction mechanism of acetalization of benzaldehyde and 2-hydroxy benzaldehyde used acid catalysts (HCl) and applied with Hyperchem software.…”

Computational calculation of acetalization of 2-chlorobenzaldehyde reaction mechanism using hydrochloric acid catalyst with ab initio method

“…The benzaldehyde dimethyl acetal compound is a compound that can be widely used in daily life. The compound has been used as a solvent in the pharmaceutical industry, detergents, varnishes, perfumes, cosmetics, food additives, and beverages (Parangi et al 2013;Li et al 2004). Besides that, acetal can also be used as motor oil, lubricant, hydraulic fluid and as an emulsion for petroleum drilling operations.…”

“…Compared with ketones, acetalization is easier between aldehyde and alcohol. The catalysts commonly used in the acetalization reaction are protonic acids, organic metal frame work (MOF) containing thiourea (Luan et al 2014), N-chlorosuccinimide/thiourea (May et al 2009), amorphous cesium phosphate (Parangi et al 2013), copper [Cu3(BTC)2] (Dhakshinamoorthy et al 2010;Jin et al 2014), and UIO 66 (Arrozi et al 2014).…”