New manganese(II) complexes with tetraorganodichalcogenoimidodiphosphinato ligands. Crystal and molecular structure of monomeric Mn[(SPMe2)(SPPh2)N]2 and dimeric [Mn{(OPPh2){OP(OEt)2}N}2(H2O)]2

Article abstract of DOI:10.1016/j.poly.2008.06.023

New manganese(II) complexes of type Mn [(XPR₂) (YP R₂^′) N]₂ [X, Y = S, R = Me, R′ = Ph (1), X = S, Y = O, R = Ph, R′ = OEt (2)] and Mn[(OPPh₂){OP(OEt)₂}N]₂(H₂O) (3), were obtained by salt metathesis reactions between MnCl₂ · 4H₂O and the potassium salts of the appropriate tetraorganodichalcogenoimidodiphosphinic acids. The complexes were characterized by EPR and IR spectroscopy, as well as by mass spectrometry. The crystal and molecular structures for 1 and 3 were determined by single-crystal X-ray diffraction. Compound 1 crystallizes as monomeric species, with the manganese(II) atom in a tetrahedral environment, while for compound 3 a dimeric structure was found. Both tetraorganodichalcogenoimidodiphosphinato ligand units behave monometallic biconnective in 1, chelating the metal centre. In the dimeric species 3 the tetraphenylimidodiphosphinato ligand units behave different, two of them chelating the manganese atoms, as monometallic biconnective moieties, while the other two act bimetallic triconnective, bridging the two metal centres. The octahedral coordination geometry in 3 is completed by water molecules. The magnetic behaviour of 3 was investigated.