pH Indicators for Strong Molecular Bases: A Theoretical Approach

Abstract

The transition points in hexamethylphosphoramide are theoretically studied for a series of acid−base indicators. Three new indicators with multiple transition points and deeply colored low-nucleophilic anions are designed. A general basicity scale is established for highly basic hexamethylphosphoramide solutions, expanding beyond the basicity of the strongest currently known molecular bases.