Feldman Aaron W, Ovaska Sami I, Ovaska Timo V
Department of Chemistry, Connecticut College, 270 Mohegan Avenue, New London, Connecticut 06320, United States of America.
Tetrahedron. 2014 Jul 8;70(27-28):4147-4155. doi: 10.1016/j.tet.2014.02.089.
Appropriately substituted 5-alkyn-1-ol systems bearing a nitrile moiety at the triple bond serve as versatile precursors to a variety of cyclooctenone derivatives via a "one-pot" base-catalyzed oxyanionic 6-exo dig cyclization/Claisen rearrangement sequence under microwave irradiation. It was found that the initially formed cyclic intermediate consists of a mixture of endo and exocyclic isomers, which appear to be in equilibrium under the reaction conditions. However, the only observed products from these reactions are α-cyano substituted cyclooctenones, derived from the exocyclic dihydrofuran intermediates.
在微波辐射下，在三键处带有腈基部分的适当取代的5-炔-1-醇体系通过“一锅法”碱催化的氧负离子6-外向环化/克莱森重排序列，作为多种环辛烯酮衍生物的通用前体。发现最初形成的环状中间体由内型和外型异构体的混合物组成，在反应条件下它们似乎处于平衡状态。然而，这些反应中唯一观察到的产物是源自外型二氢呋喃中间体的α-氰基取代的环辛烯酮。
