IR SPECTROELECTROCHEMICAL STUDIES OF THE METAL-CARBONYL DIMERS MN-2(CO)(10) AND [CPM(CO)(3)](2)(M=W, MO) - CROSS-COUPLING AND LIGAND SUBSTITUTION-REACTIONS OF ELECTROCHEMICALLY GENERATED ORGANOMETALLIC RADICALS

Reflectance IR spectroelectrochemistry (IR SEC) has been used to study the electrochemical reactions of dinuclear metal carbonyl compounds. Reduction of the dinuclear metal carbonyl complexes by two electrons yields two equivalents of the corresponding monomeric metal carbonyl anions. Upon re-oxidation, the dimeric starting materials can be re-formed in almost quantitative yields. Reactions of the dinuclear metal carbonyls include metal-metal bond homolysis reactions such as electrochemical cross-coupling reactions between Mn-2(CO)(10) and [CpM(CO)(3)](2), where M = W, Mo. The ligand substitution reaction of Mn-2(CO)(10) and PPh(3), which occurs only during the metal-metal bond homolysis reaction, is also described. The design of the anaerobic specular reflectance IR SEC cell used in these studies is also reported.