ESR Investigation of Mn Carbonyl Complexes Formed by Reaction of Mn2(CO)10 with Electron Acceptor Molecules.

The reaction of Mn(CO)10 with quinones like acenaphthenquinone (ACNQ), 9,10-phenanthrenquinone (PQ) and tetrachloro-orthobenzoquinone (o-TCBQ) yields paramagnetic adducts which have been investigated by ESR spectroscopy. While the adducts with ACNQ and PQ are obtained in a thermal reaction, the complex having o-TCBQ as a ligand requires a photoassisted reaction to be formed. In the photolysis of o-TCBQ in benzene three different adducts are formed with one, two and three o-TCBQ chelated to the manganese atom. Spin adducts are also formed when Mn2(CO)10 reacts thermally with tetracyanoquinodimethane (TCNQ) and with 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) where a coordination of the metal group to a nitrogen atom is preferred. © 1979.