V. Baudrand et al., SEPARATION AND QUANTIFICATION OF TETRAETHYLENE GLYCOL MONOHEPTANOATE AND DIHEPTANOATE BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY, Journal of chromatography, 704(2), 1995, pp. 524-529
Tetraethylene glycol mono- and diheptanoate were prepared by direct es
terification of heptanoic acid with tetraethylene glycol. The constitu
ents of the reaction were separated by thin layer chromatography with
flame ionization detection, but only tetraethyleneglycol diheptanoate
could be determined by this method. The main constituents of the react
ion mixture were quantified by HPLC using two different mobile phases
on a non-bonded silica column. Acetonitrile acidified with 0.3% acetic
acid was used to separate and quantify the monoester and tetraethylen
e glycol, while hexane-isopropanol (80:20, v/v) acidified with 0.3% ac
etic acid was used to separate and quantify heptanoic acid and the die
ster. The starting compounds and the products of the reaction could be
thus separated and quantified accurately using these two eluents with
out derivatization of the hydroxylated compounds.