Glycerol-based SO3H-Carbon Catalyst: A green recyclable catalyst for the chemoselective synthesis of pentaerythritol diacetals

Abstract

KEYWORDSGlycerol-based SO3H-functionalized carbon catalyst was demonstrated as an efficient and recyclable green catalyst for the chemoselective synthesis of pentaerythritol diacetals with aromatic aldehydes in the presence of ketones in excellent yields in toluene at 80 C. In addition, the catalyst also has the capability for the deprotection of pentaerythritol diacetals in methanol at reflux temperature. The recovered catalyst without any pre-treatment was reused for 5 cycles without any deactivation and leaching into the reaction medium under optimum conditions. Reusability Chemoselectivity Aromatic aldehydes Pentaerythritol diacetals Glycerol-based SO3H-carbon catalyst Protection and deprotection of diacetals

A rigid spirocyclic diol from fructose-based 5-hydroxymethylfurfural: synthesis, life-cycle assessment, and polymerization for renewable polyesters and poly(urethane-urea)s

“…Furthermore, the characteristic spiroacetal signals at 1201 and 1156 cm −1 (shown in the spectrum of Monomer S) were also observed in the spectra of all polyesters with increasing intensity along with the increasing S content. 71,92 This confirmed the incorporation of the spiroacetal S residues in the copolyesters.…”

“…The rationally designed rigid Monomer S was synthesized by an acid-catalyzed double acetalation of HMF and pentaerythritol (Scheme 1). 70,71 Because HMF becomes unstable at elevated temperatures under acidic conditions, it is important to minimize its degradation during the synthesis. Therefore, the stability of HMF dissolved in different solvents (and in the pure state) was screened at 25, 40 and 70°C respectively in the presence of p-toluene sulfonic acid ( p-TsOH).…”

“…Such an assignment was consistent with other similar reported compounds with spirocyclic acetal structures. 71,89 After the polymerizations, the resulting polyesters ( Fig. 3B-F) showed broadened 1 H NMR signals, indicating the formation of the polymers.…”

Degradable Spirocyclic Polyacetal-Based Core-Amphiphilic Assemblies for Encapsulation and Release of Hydrophobic Cargo

“…Compound 1 [ 43 ] (1.6 g, 4.5 mmol, 1.0 equiv.) was dissolved in acetonitrile (60 mL) in a 100 mL round bottom flask.…”

Biyodizel Yan Ürünü Olan Gliserolden Üretilen Katalizör ile Yakıt Katkı Maddesi Bütil Levulinat Sentezi

“…Ummadisetti ve arkadaşları gliserol temelli karbon katalizörü kullanarak pentaeritritol diasetallerini üretmişlerdir. Katalizörlerin aktivitesini kaybetmeden ve reaksiyon karışımında çözünmeden 5 kez kullanılabileceğini ifade etmişlerdir [14]. Ribeiro ve arkadaşları katalitik ıslak peroksit oksidasyonunda gliserol temelli karbon katalizörü kullanmışlardır.…”