Cassis and Green Tea: Spontaneous Release of Natural Aroma Compounds from β‐Alkylthioalkanones

Abstract

AbstractIn depth headspace analysis of the slow degradation of β‐alkylthioalkanones in ambient air led to the discovery of a novel δ‐cleavage pathway, by which β‐mercaptoketones are released. Since β‐mercaptoketones are potent natural aroma compounds occurring in many fruits, herbs and flowers, the discovery of an enzyme‐independent molecular precursor for this class of high‐impact molecules is of practical importance. Moreover, the formation of β‐diketones and aldehydes by concomitant oxidation at the α‐sulfur‐position enhances the versatility of this class of aroma precursors. A mechanistic model is proposed which suggests that the oxidative degradation occurs through a novel Pummerer‐type rearrangement of initially formed persulfoxides.