Ammonium ion species

Excluding consideration of a multitude of representatives of solvent extraction classes (water-insoluble alcohols, ethers, acids, esters, ketones and diketones) that have been examined and found to be inadequate in some respect or another, it is the intent here to focus upon only a few representatives of just three classes of extractants (1) neutral phosphorous agents (2) monoacidic orthophosphate and phosphonate esters and (3) primary, secondary, tertiary and quaternary ammonium ion species. 

Photol) is of the phenolate ion (at high pH) failed to cause reaction, indicating that an initial ESIPT from phenol to the Mannich base is required to form the ammonium ion species, which then fadhtates its departure as a leaving group. 

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