Stereoselective Synthesis of Highly Substituted Tetrahydropyrans through an Evans Aldol–Prins Strategy
作者:Sergio J. Álvarez-Méndez、Marta Fariña-Ramos、María Luisa Villalba、Marcelle D. Perretti、Celina García、Laila M. Moujir、Miguel A. Ramírez、Víctor S. Martín
DOI:10.1021/acs.joc.8b01182
日期:2018.8.17
position. From these alcohols were also obtained halogenated pentasubstituted tetrahydropyrans as well as 2,3,4,5-tetrasubstituted tetrahydrofurans, shedding light on the mechanism of the process. Computational studies were consistent with the experimental findings, and this innovative Evans aldol–Prins strategy was performed for the preparation of a battery of more than 30 densely substituted tetrahydropyrans
已经开发出一种直接和通用的合成天然存在的2,3,4,5,6-五取代的四氢吡喃的方法,该方法使用β,γ-不饱和的N-酰基恶唑烷-2-酮作为关键原料。Evans aldol加成和Prins环化的结合使得可以以两种方式非对映选择性和有效地生成所需的oxacycle:一锅Evans aldol–Prins协议,其中直接生成了五个新的σ键和五个连续的立体中心,并且两步法,另外可以分离带有N的β,γ-不饱和醇前体-酰基恶唑烷-2-酮在α位。从这些醇中还获得卤化的五取代的四氢吡喃以及2,3,4,5-四取代的四氢呋喃,这阐明了该方法的机理。计算研究与实验结果一致,这项创新的Evans aldol–Prins策略用于制备30多个紧密取代的四氢吡喃电池,该电池前所未有地与1,3-恶嗪烷-2,4-二酮环稠合,外消旋形式和对映体形式。这些新颖的分子已成功进行了数次转化,可轻松获得各种不同功能的四氢吡喃。建立了白色念珠菌和一些构效关系。