Steric-switched defluorofunctionalization selectivity: controlled synthesis of monofluoroalkene-masked medium-sized heterocyclic lactams and lactones
作者:Hao Zeng、Hengyuan Li、Huanfeng Jiang、Chuanle Zhu
DOI:10.1007/s11426-021-1135-8
日期:2022.3
defluorinative functionalization of two C(sp3)-F bonds in a CF3 group. Various attractive monofluoroalkene-masked medium-sized heterocyclic lactams and lactones are obtained in moderate to excellent yields. Simple derivation of these masked-heterocycles efficiently affords useful skeletons of lactams, lactones, and 1,4-oxazepanes in a single diastereoisomer. Mechanism studies indicate that a unique sequential
(三氟甲基)烯烃与氨基醇和二胺的空间转换同去氟胺化触发和同去氟氧化触发环化是在温和条件下实现的。这种区域选择性策略通过 CF 3中两个 C(sp 3 )-F 键的顺序脱氟官能化来区分氨基醇和不对称二胺中的不同亲核杂原子位点团体。各种有吸引力的单氟烯烃掩蔽的中等大小的杂环内酰胺和内酯以中等至优异的产率获得。这些掩蔽杂环的简单衍生有效地提供了单一非对映异构体中的有用的内酰胺、内酯和 1,4-氧氮杂环己烷骨架。机理研究表明,独特的顺序ipso -/ γ -选择性脱氟功能化途径参与了这些转化。