Xiong Qiang, Lu Ji, Shi Liu, Ran Guang-Yao
Department of Medicinal Chemistry, College of Pharmacy, Chongqing Medical University, Chongqing 400016, China.
College of Pharmacy, Southwest Medical University, Luzhou 646000, China.
Org Lett. 2022 May 13;24(18):3363-3367. doi: 10.1021/acs.orglett.2c01114. Epub 2022 May 2.
An annulation of phthalide-derived activated alkenes is initially disclosed in this work. Specifically, we have developed an unprecedented [5 + 2] cycloaddition/ring-contraction tandem process of activated tetrasubstituted alkenes derived from phthalides or butyrolactone with vinylethylene carbonates under Pd(0) catalysis. Differing from the traditional spirolactonization strategy, this method renders an efficient and mechanistically distinct approach to benzo-[5,5]-spiroketal lactones and [5,5]-spiroketal lactones bearing two vicinal tetrasubstituted centers with high diastereoselectivity.
本研究首次披露了邻苯二甲酸内酯衍生的活性烯烃的环化反应。具体而言，我们开发了一种前所未有的[5 + 2]环加成/环收缩串联反应，即在钯(0)催化下，使邻苯二甲酸酯或丁内酯衍生的活性四取代烯烃与碳酸乙烯基乙烯酯发生反应。与传统的螺内酯化策略不同，该方法为合成具有两个相邻四取代中心的苯并-[5,5]-螺缩酮内酯和[5,5]-螺缩酮内酯提供了一种高效且机理独特的方法，具有高非对映选择性。
