AbstractHerein, we have synthesized multifunctionalized 2‐oxa‐3‐azabicyclo[3.1.1]heptanes, which are considered potential bioisosteres for meta‐substituted arenes, through Eu(OTf)3‐catalyzed formal dipolar [4π+2σ] cycloaddition of bicyclo[1.1.0]butanes with nitrones. This methodology represents the initial instance of fabricating bicyclo[3.1.1]heptanes adorned with multiple heteroatoms. The protocol exhibits both mild reaction conditions and a good tolerance for various functional groups. Computational density functional theory calculations support that the reaction mechanism likely involves a nucleophilic addition of nitrones to bicyclo[1.1.0]butanes, succeeded by an intramolecular cyclization. The synthetic utility of this novel protocol has been demonstrated in the concise synthesis of the analogue of Rupatadine.
摘要在本文中,我们通过 Eu(OTf)3 催化双环[1.1.0]丁烷与硝基化合物的形式二极 [4π+2σ] 环加成,合成了多功能的 2-oxa-3-azabicyclo[3.1.1]heptanes (被认为是元取代的炔类化合物的潜在生物寄主)。该方法是制造缀有多个杂原子的双环[3.1.1]庚烷的首个实例。该方法不仅反应条件温和,而且对各种官能团具有良好的耐受性。计算密度泛函理论计算表明,反应机理可能是硝基与双环[1.1.0]丁烷发生亲核加成反应,然后发生分子内环化反应。在鲁帕他定类似物的简易合成过程中,证明了这种新方法的合成用途。