Time-programmable pH: decarboxylation of nitroacetic acid allows the time-controlled rising of pH to a definite value

Autor: Gianfranco Ercolani, Daniele Del Giudice, Cecilia Bombelli, Emanuele Spatola, M. Valentini, Stefano Di Stefano
Rok vydání: 2021
Předmět:
Zdroj: Chemical Science
ISSN: 2041-6539
2041-6520
DOI: 10.1039/d1sc01196k
Popis: In this report it is shown that nitroacetic acid 1 (O2NCH2CO2H) can be conveniently used to control the pH of a water solution over time. Time-programmable sequences of the kind pH1(high)–pH2(low)–pH3(high) can be achieved, where both the extent of the initial pH jump (pH1(high)–pH2(low)) and the time required for the subsequent pH rising (pH2(low)–pH3(high)) can be predictably controlled by a judicious choice of the absolute and relative concentrations of the reagents (acid 1 and NaOH). Successive pH1(high)–pH2(low)–pH3(high) sequences can be obtained by subsequent additions of acid 1. As a proof of concept, the method is applied to control over time the pH-dependent host–guest interaction between alpha-cyclodextrin and p-aminobenzoic acid.
Predictable and time-programmable sequences of the kind pH1(high)–pH2(low)–pH3(high) in water solution are obtained by a judicious choice of the concentration of nitroacetic acid undergoing decarboxylation.
Databáze: OpenAIRE