Reactivity and Diastereoselectivity in Inverse- Type Hetero-Diels-Alder Dihydropyran Syntheses
作者:Satyam Apparao、Martin E. Maier、Richard R. Schmidt
DOI:10.1055/s-1987-28114
日期:——
β-Acyloxy-α-phenylthio-substituted α,β-unsaturated carbonyl compounds 3a-i and 4c, f, having different electron withdrawing carbon substituents at the carbonyl group, afford with ethyl vinyl ether as heterodienophile the dihydropyrans 5a-i and 6c, f, respectively. The endo/exo-diastereoselectivity of these reactions, providing versatile intermediates for carbohydrate and related natural product syntheses, is discussed.
δ-酰氧基-δ-苯硫基取代的δ,δ-不饱和羰基化合物 3a-i 和 4c、f,在羰基上具有不同的取电子碳取代基,以乙烯基乙基醚为杂二亲和基,可分别生成二氢吡喃 5a-i 和 6c、f。讨论了这些反应的内/外-非对映选择性,为碳水化合物和相关天然产物的合成提供了多功能中间体。