A Novel<i>bis</i>-Lactonisation of Naphtho- and Phenanthro-1,2-Dioxines with Malonate Nucleophiles
作者:Dennis K. Taylor、Ben Greatrex、Martyn Jevric、Marc C. Kimber、Sara J. Krivickas、Edward R. Tiekink
DOI:10.1055/s-2003-38073
日期:——
mild to rearrange the 1,2-dioxines to yield the transient cis-γ-hydroxy enone species with no further Kornblum-DeLaMare rearrangement. The cis-γ-hydroxy enones readily undergo conjugate addition by malonate nucleophiles in a highly diastereoselective fashion. An intramolecular domino cyclisation then ensues yielding the observed bis-lactones. The relative configuration of the bis-lactone series was established
丙二酸亲核试剂以共轭方式添加到取代的萘并 phenanthro-1,2-dioxines 中,以高产率和高 de 提供官能化双内酯。丙二酸亲核试剂的碱性足够温和,可以重新排列 1,2-二恶英,从而产生瞬态的 cis-γ-羟基烯酮物质,而无需进一步的 Kornblum-DeLaMare 重排。顺式-γ-羟基烯酮很容易通过丙二酸亲核试剂以高度非对映选择性的方式进行共轭加成。然后发生分子内多米诺环化,产生观察到的双内酯。双内酯系列的相对构型通过1-和2-D 1 H, 1 3 C NMR技术确定,并通过单晶X射线分析进一步证实。