Robust Alkyne Metathesis Catalyzed by Air Stable d2 Re(V) Alkylidyne Complexes

We report in this communication the
first example of catalytic
alkyne metathesis reactions mediated by well-defined non-d0 alkylidyne complexes. The air-stable d2 Re­(V) alkylidyne
complex Re4, bearing two PO-chelating ligands and a labile
pyridine ligand, could catalyze homometathesis of internal alkynes
with a broad substrate scope, including alcohols, amines, and even
carboxylic acids. The catalyst can tolerate heating, air, and moisture
in both solid and solution states, and the catalytic metathesis reactions
could proceed normally in wet solvents.

本通讯中，我们首次报道了由明确界定的非d0型烷基化复合物介导的催化炔烃交换反应。该空气稳定的d2 Re(V)烷基化复合物Re4，携带有两个PO螯合配体和一个易解离的吡啶配体，能够催化内部炔烃的同分异构化反应，其底物范围广泛，包括醇、胺，甚至羧酸。该催化剂在固态和溶液状态下均能耐受加热、空气和湿度，催化交换反应在潮湿溶剂中仍能正常进行。