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Phosphate ester cleavage by a positively charged porous silica adorned with lanthanum (III)
Ist Teil von
Microporous and mesoporous materials, 2018-09, Vol.268, p.144-152
Ort / Verlag
Elsevier Inc
Erscheinungsjahr
2018
Link zum Volltext
Quelle
Elsevier ScienceDirect Journals Complete
Beschreibungen/Notizen
Phosphate esters and analogs thereof are well known in chemistry and biology by their formidable stability. We used a porous silica material (PSiM) functionalized with amino groups (8.4%) and lanthanum ions (1.5%) to catalyze the cleavage of bis(2,4-dinitrophenyl)phosphate (BDNPP). The functionalized PSiM attracted the substrate from solution and accelerated its hydrolysis by 38-fold in relation to the uncatalyzed reaction at pH 8.14. After an induction period associated to hydration of the catalyst during the first use, the catalytic activity increased in the first reuse to about 600-fold. Supramolecular effects were proposed to drive the catalytic process. Kinetic studies in different pH's showed that the lanthanum ion and amino groups acted mutually in the BDNPP hydrolysis and a reaction mechanism that took this into account was proposed.
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•An aminated porous silica material was decorated with lanthanum ions (1.5%).•The silica material catalyzed the hydrolysis of bis(2,4-dinitrophenyl)phosphate.•After an induction period the catalytic activity increased from 38-fold to 600-fold.•The activity was maxima near neutral conditions.