92686-31-2Relevant articles and documents
Anodic Dimerization of Enamines, 2-Cyano-2-phenylvinylamines
Masui, Masaichiro,Ueda, Chihiro,Moriguchi, Toshihide,Michida, Takashi,Kataoka, Michiko,Ohmori, Hidenobu
, p. 1392 - 1400 (2007/10/02)
The effects of substituents (R1, R2, and R3) on the electrochemical oxidation of the title enamines, R1-C6H4-C(CN)=CH-NR2R3 (1) were investigated in acetonitrile at a glassy carbon electrode together with the oxidation of a related amine, Ph-CH(CN)-CH2-NMe2 (5).Cyclic voltammetry of 1 showed two or more anodic peaks depending upon the substituents.On controlled potential electrolysis at the potential of the first anodic wave, 1 with R1 = H, R2 = alkyl, and R3 = alkyl or H gave diphenylmethane derivatives in which two molecules of the starting enamine are coupled between the β-carbon atom and the phenyl ring para to the enamino group.Essentially the same results were obtained for 1 with R1 = m-Me or m-Cl and R2 = R3 = Me.A mechanism involving the dimerization of radical cations from 1 is proposed.Electrolysis of 1 with R1 = p-Cl or p-Me and R2 = R3 = Me, on the other hand, gave diphenylethane derivatives via coupling between the β-carbon atoms.No stable product was obtained from 1 with a phenyl group on the nitrogen atom.Results on electrolyses of the amine 5 and 1 with R1 = H and R2 = R3 = Me at the voltammetric peak potential of 5 argue against the possibility that an enamine is formed as an intermediate in the electrochemical dealkylation of aliphatic amines.Keywords - β-cyanoenamine; oxidative dimerization; radical cation; electrochemical oxidation; cyclic voltammetry; controlled potential electrolysis, ESR spectrum.
