Manganese(I) and Rhenium(I) Chelate Complexes with 2-Azabutadienes (RS)2C=C(H)-N=CPh2: Topological AIM Bonding Analysis and Molecular Structure of fac-MnBr(CO)3[(iPrS)2C=C(H)-N=CPh2]

The thioether-functionalized 2-azabutadiene (iPrS)2C=C(H)-N=CPh2 L1 ligates to Mn(CO)5Br to form the five-membered chelate compound fac-MnBr(CO)3[(iPrS)2C=C(H)-N=CPh2] MnPropBr, whose crystal structure has been determined from X-ray diffraction data. In the crystal, different secondary intermolecular interactions, such as Br…HC and π…π, give rise to a supramolecular network. The electronic properties of the metal–ligand bonds in MnPropBr are similar to those of complex MnPhBr (with R = SPh instead of iPrS); this also applies to a series of structurally analogous fac-ReX(CO)3[(RS)2C=C(H)-N=CPh2] (X = Cl, Br and I; R = SiPr, SPh and StBu) rhenium complexes and are discussed on the basis of QT-AIM (Quantum Theory of Atoms in Molecules) calculations. New bond length/electron density relationships are proposed for the metal–halide bonds, including, for the first time, complexes of one given metal and all three corresponding halides. In order to obtain a set of coherent data, three manganese complexes that belong to the family fac-MnX(CO)3[N∩N] (X = Cl, Br and I; N∩N is a chelating ligand with two coordinating N atoms) were included in this study.