我们通过概念上不同的扩环策略开发了一种有效的中环和大环内酯合成方法。The design of an unprecedented ring conjunction mode of oxetene, combined with the appropriate choice of a Lewis acid promoter and an additive, constitutes the key components of the new process. 通过这种新方法,反应不需要高度稀释或缓慢添加。
Silver-Promoted Benzannulations of Siloxyalkynes with Pyridinium and Isoquinolinium Salts
作者:Jaime R. Cabrera-Pardo、David I. Chai、Sergey A. Kozmin
DOI:10.1002/adsc.201300443
日期:2013.9.16
efficient benzannulations of siloxyalkynes with pyridinium and isoquinolinium salts. Such reactions are successfully promoted by a stoichiometric amount of silver(I) benzolate under mild reaction conditions. This process proceeds via a formal inverse‐electron demand Diels–Alder reaction, followed by fragmentation of the initially produced bicyclic adducts to deliver a range of synthetically useful phenols
Catalytic Ring Expansion of Cyclic Hemiaminals for the Synthesis of Medium‐Ring Lactams
作者:Wanxiang Zhao、Hui Qian、Zigang Li、Jianwei Sun
DOI:10.1002/anie.201504926
日期:2015.8.17
A mild and efficient intermolecular ring‐expansion approach was developed for the synthesis of medium‐ringlactams by using siloxy alkynes. Key to success is the suitable combination of a superior catalyst and an exceptional nitrogen‐protecting group. Control experiments indicated that the reaction is remarkably selective toward the desired lactam formation, even with many possible non‐productive pathways