US Patent 7642363 Process for the preparation of 2-(6-substituted-1,3-dioxane-4-YL) acetic acid derivatives

The invention relates to the preparation of 2-(6-substituted-1,3-dioxane-4-yl)acetic acid derivatives of formula 1, where X stands for a leaving group, and R1, R2, and R3 each independently stand for an alkyl group with 1-3 carbon atoms from 4-hydroxy-6-X-substituted-methyl-tetrahydropyran-2-one compounds, where X is as defined above, with the aid of an acetalization agent, in the presence of an acid catalyst.