83311-75-5Relevant academic research and scientific papers
Ligand effects on CO bridging in binuclear manganese carbonyl complexes
Wolff, Thomas E.,Klemann, Lawrence P.
, p. 1667 - 1670 (1982)
Reactions between Mn2(CO)10, (C2H6)2PCH2PPh2(depm), and (c-C6H11)2PCH2PPh2(dcpm) (depm = Et2PCH2PPh2 and depm = (c-C6H11)2PCH2PPh2) in refluxing decane gave binuclear complexes Mn2-(CO)6(depm)2 and Mn2(CO)5(depm)2, respectively. A solution of the depm complex could be decarbonylated to give Mn2(CO)5(depm)2 whose attempted isolation resulted in disproportionation to the starting hexacarbonyl and unidentified decomposition products. Carbonylation of Mn2(CO)6(dcpm)2 afforded Mn2(C0)g(dcpm)2 which slowly reverts to the starting pentacarbonyl in the absence of a CO partial pressure. Solutions of both pentacarbonyl complexes show a low frequency (1640 cm'1) CO stretch assigned to a four-electron bridging carbonyl (4EBC) ligand. Comparing diphosphine ligand electronic and steric characteristics, the steric demand of the ligand appears to dominate as the factor responsible for stabilization of the four-electron bridging carbonyl in dimanganese pentacarbonyl systems.
