Synthesis, characterization, X-ray structures, and catalytic activity of new Mn(I) and Re(I) metal complexes of chelating phosphinopyridylamine and its sulfide ligands.

The reaction of 4-Me-C5H3N-2-NH(PPh2) (1) with Mn(CO)5Br in refluxing chloroform produced the fac-[Mn(CO)3Br{1-?2P,N}] (2) and [Mn(CO)2{1-?2P,N}2]Br (3) complexes. Furthermore, the refluxing of the monooxidized thioyl (4-CH3)C6H3N-2-NH(P(S)Ph2) (4) ligand with M(CO)5Br (M = Mn, Re) in chloroform yielded the fac-[M(CO)3Br{4-?2S,Npy}] (M = Mn (5), Re(6)) complexes. The investigation of complexes 2, 3, 5, and 6 was carried out with the use of multinuclear NMR (1H, 13C and 31P NMR), infrared spectroscopy, and the determination of crystal structures. Complexes 5 and 6 represent the inaugural structurally characterized instances of this category of chalcogenide ligands associated with Mn and Re metals documented thus far. Complexes 5 and 6 demonstrate significant catalytic efficacy in the hydrogenation of acetophenone derivatives to yield 1-phenylethanol derivatives, utilizing 2-propanol as a hydrogen source.