The present invention relates to an improved process for the production of 4-alkanoyloxy-2-methylbutanoic acid, as well as to the use of such compounds in organic syntheses, especially in processes forming intermediates (building blocks) for the synthesis of organic compounds comprising isoprene (isoterpene) units, such as β-carotene or other carotenoids (e.g. canthaxanthin, zeaxanthin or astaxanthin) or as vitamin E or vitamin A as well as other structurally similar compounds.