Water-catalyzed iron-molybdenum carbyne formation in bimetallic acetylene transformation
Xiaofang Zhai, Minghui Xue, Qiuting Zhao, Qiu-Cui Zheng, Datong Song, Chen‐Ho Tung, Wenguang Wang
Abstract
Transition metal carbyne complexes are of fundamental importance in carbon-carbon bond formation, alkyne metathesis, and alkyne coupling reactions. Most reported iron carbyne complexes are stabilized by incorporating heteroatoms. Here we show the synthesis of bioinspired FeMo heterobimetallic carbyne complexes by the conversion of C2H2 through a diverse series of intermediates. Key reactions discovered include the reduction of a μ-η2:η2-C2H2 ligand with a hydride to produce a vinyl ligand (μ-η1:η2-CH = CH2), tautomerization of the vinyl ligand to a carbyne (μ-CCH3), and protonation of either the vinyl or the carbyne compound to form a hydrido carbyne heterobimetallic complex. Mechanistic studies unveil the pivotal role of H2O as a proton shuttle, facilitating the proton transfer that converts the vinyl group to a bridging carbyne. Bioinspired Fe-Mo complexes are promising for the activation of small molecules, offering valuable insights into the interactions and transformations of unsaturated hydrocarbons with abundant metals. Here, the authors report the synthesis and mechanistic studies of FeMo carbyne complexes and unveil the pivotal role of H2O as a proton shuttle.