REDUCTION OF HEXAAZACYCLOPHANE COMPLEXES OF CO(II) AND CU(II) BY CENTER-DOT-CH2OH AND E(SOL)(-) - A PULSE-RADIOLYSIS STUDY

The reactions of (CH2OH)-C-. and e(sol)(-) with hexaazacyclophane comp lexes of Co(II) and Cu(II) in methanol and or methanol-water mixed sol vents were investigated by pulse radiolysis. The primary products from the reduction of the macrocyclic complexes were assigned a radical na ture by comparing their optical spectra with those of related Co(I) an d Cu(I) species. Such metal-ligand radical products undergo disproport ionations. The product of the disproportionation was assigned as a Co( III)-hydride complex. Although a similar hydride could be produced in the disproportionation of the Cu(II)-ligand radical, the optical spect rum of the product is in accordance with the hydrogenation of a double bond in the ligand. Interception of the metal-ligand radical intermed iates with CO2 resulted in the formation of adducts.