Spin delocalization in retinals.
A 220-MHz proton nuclear magnetic resonance study of the binding of Ni(II) and Co(II) acetylacetonates to retinyl-N-methyl Schiff's bases is presented. The study has yielded the magnitude and sign of spin densities at the carbon atoms in the pi system of the 9-cis, 13-cis, and all trans isomers. From a comparison of the experimental results with molecular orbital calculations, a mechanism for transfer of spin from the metal to the retinyl Schiff's base and its subsequent delocalization down the polyene chain is provided.
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003035:Cobalt; D007097:Imines; D009682:Magnetic Resonance Spectroscopy; D009532:Nickel; D013237:Stereoisomerism; D014801:Vitamin A / Q000032:analysis*
D007097:Imines; D014801:Vitamin A; D003035:Cobalt; D009532:Nickel