Synthesis, Structure and Cu‐Phenylacetylide Coordination of an Unsymmetrically Substituted Bulky dppf‐Analog

Abstract The donor properties of a set of bulky ferrocene based bisphosphanes (Fe(C 5 H 4 PMes 2 ) 2 and (C 5 H 4 PMes 2 )Fe(C 5 H 4 P t Bu 2 with Mes= mesityl and t Bu= tert ‐butyl) were probed by exploring the NMR parameters of the corresponding selenophosphoranes amended by cyclovoltammetry. The ligand properties were explored in the complexation of copper phenylacetylide which is relevant as intermediate in the Cu(I) catalyzed CO 2 addition to phenylacetylene. Owing to the poor solubility of the resulting complexes their characterization was performed with solid state NMR spectroscopy amended by IR spectroscopy, mass spectrometry and elemental analysis. Remarkably, these complexes feature luminescent properties, albeit with limited quantum yield.