PHOTOCHEMICAL DECOMPOSITION AND CARBON MONOXIDE INSERTION IN ORGANOMETALLIC COBALT CHELATES

From photoreaction of RCo(Salen). H2O [R = Ch3, C2H5, C3H7, C4H9; Salen=bis (salicylaldehyde) ethylenediiminato] with carbon monoxide in R'OH as solvent (R′=CH3, C2H5, iso-C3H7) and in the presence of oxygen (R′OCO)Co(Salen). H2O is produced. The reaction occurs in two steps, photoreaction of RCo(Salen). H2O giving R′OCo(Salen)being followed by a true insertion of carbon monoxide into the cobalt-oxygen bond. In anaerobic conditions, even in presence of carbon monoxide, only a homolytic cleavage of carbon-cobalt bond takes place given CoII(Salen). When other planar tetradentate systems are used in place of Salen the same kind of reaction occurs. © 1968.