Synthesis of Mono- and Diunsaturated Esters of TADDOL

ABSTRACT The synthesis of fourteen new mono- and diesters of (4R,5R)-2,2-dimethyl-α,α,α′,α′-tetraphenyl-1,3-dioxolane-4,5-di­methanol (TADDOL) is reported. This study shows that esterifications of TADDOL (1) with acid chlorides, derived from normal and α,β-unsaturated carboxylic acids, in the presence of N-butyllithium (BuLi) can lead to both mixtures of the corresponding mono- and diesters, the latter in higher yield, and to just the diesters, depending on the structure of the starting acids. These reactions take place in most cases in good to excellent overall yields (57-95%). The reaction between a dichloro derivative of TADDOL and the silver salts of α,β-unsaturated acids also gives the corresponding unsaturated diesters of TADDOL in good yields.