| Abstract
| - An investigation into the endo/exo selectivity and π-diastereofacial selectivity of ester-tetheredintramolecular Diels−Alder reactions is reported. High levels of exo selectivity are realized withterminally substituted dienophiles, and high lk π-diastereofacial selectivities are induced by thepresence of a bulky dioxolanyl substituent at the allylic position of the tether. Precursors 19S,20S, and 21S, readily prepared from glucose, provide densely functionalized bicyclic lactones ofpredictable stereochemistry in high yields in enantiomerically pure form upon thermolysis at 110°C. B3LYP/6-31G(d) theory provides good descriptions of transition structures for these reactionsand allows an understanding of the formation of the major cycloadducts.
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