Ternary copper-incorporated group 8 (Ru or Fe) carbonyl chalcogenide complexes and polymers: From syntheses to applications

Main-group element-containing mixed-metal carbonyl complexes represent an important field of contemporary chemistry. This account will focus on the development of Cu-incorporated group 8 (Ru or Fe) carbonyl chalcogenide complexes, and will represent a review and discussion, mainly from our group and others, of the rational synthetic methodologies, controlled cluster-growth processes, transformations, as well as their special applications in areas of semiconductors and catalysis. The description of this review is arranged by four types of building blocks, ERu₅-, Te₂Ru₄Cu₂-, EFe₃-, and TeFe₃Cu₂-based (E = Te, Se, S) carbonyl clusters, which can further react with copper sources, CuX (X = Cl, Br, I) and [Cu(MeCN)₄][BF₄], or toward inorganic and organic reagents to construct the ternary E‒M‒Cu‒CO (M = Ru, Fe) complexes or polymers. The NHC-decorated TeFe₃Cu₂-based complexes exhibited pronounced catalytic activities toward the homocoupling of arylboronic acids with low copper loadings and high yields. Further, the energy gaps of these ternary carbonyl complexes were systematically studied in terms of chalcogen and halide effects, and most importantly, the size and dimensionality of these complexes.