Enantioselective Synthesis of Cyclobutenes by Intermolecular [2+2] Cycloaddition with Non‑C2 Symmetric Digold Catalysts

The enantioselective intermolecular gold­(I)-catalyzed [2+2] cycloaddition of terminal alkynes and alkenes has been achieved using non-C2-chiral Josiphos digold­(I) complexes as catalysts, by the formation of the monocationic complex. This new approach has been applied to the enantioselective total synthesis of rumphellaone A.本研究以非C2手性Josiphos型双金(I)配合物为催化剂，通过单阳离子配合物（monocationic complex）的形成路径，成功实现了端炔烃（terminal alkynes）与烯烃（alkenes）的对映选择性分子间金(I)催化[2+2]环加成反应。该全新策略已应用于棕壳菌素A（rumphellaone A）的对映选择性全合成。