Synthesis and crystal structures of manganese(I) carbonyl complexes bearing ester-substituted α-di-imine ligands

Abstract

The crystal structures of two manganese(I) complexes with ester-substituted bi-pyridine or bi-quinoline supporting ligands are reported, namely, fac-bromido-tricarbon-yl(diethyl 2,2'-bi-pyridine-4,4'-di-carboxyl-ate-κ² N,N')mangan-ese(I), [MnBr(C₁₆H₁₆N₂O₄)(CO)₃], I, and fac-bromido-tricarbon-yl(diethyl 2,2'-bi-quinoline-4,4'-di-carboxyl-ate-κ² N,N')manganese(I), [MnBr(C₂₄H₂₀N₂O₄)(CO)₃], II. In both complexes, the manganese(I) atom adopts a distorted octa-hedral coordination sphere defined by three carbonyl C atoms, a Br^- anion and two N atoms from the chelating α-di-imine ligand. Both complexes show fac configurations of the carbonyl ligands. In I, the complex mol-ecules are linked by C-H⋯Br hydrogen bonds and aromatic π-π contacts. In II, intra-molecular C-H⋯O hydrogen bonds are present as well as inter-molecular C-H⋯O and C-H⋯Br hydrogen bonds and π-π inter-actions.

Keywords: bipyridyl ligand; biquinolyl ligand; crystal structure; ester substituent; manganese(I) complex.