Carbon monoxide release properties and molecular structures of phenylthiolatomanganese(I) carbonyl complexes of the type [(OC)(4)Mn(mu-S-aryl)](2)

摘要

Several phenylthiolatomanganese carbonyl complexes of the type [(OC)(4)Mn(mu-SR)](2) (R = Ph (1a), C6H4-4-CH3 (1b), C6H4-4-CF3 (1c), C6H4-4-F (1d), C6H4-4-Cl (1e), C6H4-4-OMe (1f), C6F5 (1g), and CH2C6H4-4-Cl (1h)) have been prepared via the reaction of Mn-2(CO)(10) with diaryldisulfane or via the reaction of [(OC)(5)MnBr] with arylthiols. These complexes lose two carbon monoxide molecules quite easily yielding tetranuclear [(OC)(3)Mn(mu(3)-SR)](4) (2). Derivatives with fluoro-substituted aryl groups commonly form mixtures of dinuclear 1 and tetranuclear 2 which can quantitatively be converted to 2 by heating of the corresponding reaction mixtures. A unique trinuclear structure is found for the mesityl derivative [(OC)(4)Mn(mu-SMes)](3) (3) which is maintained in solution as verified by IR and NMR spectroscopy. Traces of an already known dinuclear by-product of the type [(OC)(3)Mn(mu-SC6H3(-4-Me)-2-SC6H4-4-Me)](2) (4) have been structurally characterized. The suitability of [(OC)(4)Mn(mu-SPh)](2) (1a) as a CO releasing molecule (CORM) for the administration of carbon monoxide has been studied. Two CO molecules are released upon dissolving in strongly Lewis basic solvents L, yielding [(OC)(3)Mn(L)(mu-SPh)](2), which liberates all the remaining CO molecules upon irradiation (photoCORM behavior).