INTRAMOLECULAR CATALYSIS OF DIALKYL OMEGA-AMINOALKYLPHOSPHONATE HYDROLYSIS

The influence that intramolecular catalysis of hydrolysis of 0-alkyl S-[2-(dialkylamino)ethyl] alkylphosphonothioates by amino groups may have on the product distribution of the reaction is investigated by study of a series of model compounds. The hydrolysis of diethyl [omega-(ethylamino)alkyl]phosphonates and diethyl [omega-(diethylamino)alkyl]phosphonates has been investigated at 75-degrees-C over the pH range 8.21-11-45. Contributions to hydrolysis of the ethoxy groups by intramolecular catalysis by the amino groups have been identified for [2-(amino)ethyl]- and [3-(amino)propyl]-phosphonates. Secondary and tertiary amino groups assist hydrolysis through general base catalysis. An additional contribution to hydrolysis of the secondary amino compounds by intramolecular nucleophilic catalysis is also observed.