The Enzymatic Synthesis and Characterization of Disolketal Iminodiacetic Acid (DSIDA)

Abstract

AbstractDisolketal iminodiacetic acid (DSIDA) has been synthesized from the enzyme‐catalyzed condensation reaction between derivatives of iminodiacetic acid (IDA) and glycerol. According to all available literature, DSIDA is a novel diester that has never been synthesized. It is a precursor to water‐soluble polyhydric alcohols and helps to address the global need of the biodiesel industry to find new uses for glycerol. Reacting diMe‐IDA with solketal, a protected glycerol, produced DSIDA in yields as high as 96.4% under optimal reaction conditions of 70 °C and 200 Torr for 24 h. The reaction was monitored using ATR‐IR and a validated GC method. ATR‐IR monitored the disappearance of the primary solketal alcohol and the appearance of cyclic solketal ether bonds in the molecular backbone of the intermediates and product. Structural analysis of the intermediates and products was performed using two‐dimensional NMR, GC, GC–MS and elemental analysis. All spectral data was in agreement with the proposed structures for the chemical reaction. Thermal profiles were determined by TGA to be single‐stage decompositions above 160 °C.