California Institute of Technology, The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, USA.
Angew Chem Int Ed Engl. 2017 Sep 4;56(37):11213-11216. doi: 10.1002/anie.201704670. Epub 2017 Jul 12.
A highly efficient, Z-selective ring-closing metathesis system for the formation of macrocycles using a stereoretentive, ruthenium-based catalyst supported by a dithiolate ligand is reported. The catalyst is remarkably active as observed in initiation experiments showing complete catalyst initiation at -20 °C within 10 minutes. Macrocyclization reactions generated Z-products from easily accessible diene starting materials bearing a Z-olefin moiety. This approach provides a more efficient and selective route to Z-macrocycles relative to previously reported systems. Reactions were completed within shorter reaction times, and turnover numbers of up to 100 could be achieved. Macrocyclic lactones ranging in size from twelve- to seventeen-membered rings were synthesized in moderate to high yields (67-79 %) with excellent Z-selectivity (95-99 %).
报道了一种使用立体保留的、基于钌的催化剂与二硫代配体形成的高效、Z 选择性的环 closing metathesis 系统，用于形成大环化合物。在引发实验中观察到催化剂具有很高的活性，在 -20°C 下 10 分钟内完全引发催化剂。环化反应从容易获得的带有 Z-烯烃部分的二烯起始原料生成 Z-产物。与以前报道的体系相比，该方法提供了一种更有效和选择性的方法来制备 Z-大环化合物。反应在较短的反应时间内完成，最高可达 100 的周转数。合成了大小从十二元环到十七元环的环内酯，产率中等至高产率（67-79%），具有优异的 Z 选择性（95-99%）。
