A series of novel 3-N,N-dimethylaminofunctionalized phosphinines were synthesized and structurally characterized. DFT calculations showed that these aromatic phosphorus heterocycles possess stronger π-donor and σ-donor properties compared to the parent phosphinine C5H5P. With CuBr ⋅ SMe2, the corresponding complexes of the type [(phosphinine)2CuBr]2 are formed, which show the classical terminal σ-coordination mode of the phosphorus donor towards the Cu(I) center. Upon reaction with AuCl ⋅ SMe2, mononuclear phosphinine-Au(I)Cl complexes could be obtained and crystallographically characterized. Moreover, the presence of a SiMe3-group and a donor-functionality provide the possibility for post-synthetic ligand modifications. With CuCl ⋅ SMe2 the phosphinine-based hydrochloride salts forms a rare Cu(I) complex with a Cu4Cl4-core, that contains two pairs of differently coordinating phosphinine ligands.
