2:2-Dimethyl-1:3-propanediol-hydroxypivalic acid monoester, useful as raw material in the manufacture of synthetic resins and plasticisers, is produced from 2:2-dimethyl-3-hydroxypropanol obtained by reacting HCHO with isobutyraldehyde at elevated temps. in the presence of tert. amines. This reaction mixture, after removal of free amine, is then reacted at 120 - 175 degrees C in the presence of an organic salt of a tert. amine of mol. wt. below 250.
