Utilisation du cyanure de tetraethylammonium pour la preparation de complexes cyclopentadienyl fer cyclohexadienyl cyanes. Etude de leur oxydation electrochimique et chimique

Article abstract of DOI:10.1016/0022-328X(95)05553-2

Addition of tetraethylammonium cyanide to a solution of η⁵-cyclopentadienyl)(η⁶-arene)iron (1 +), in acetonitrile can be studied by voltammetry.With electron-withdrawing groups such as nitro, keto, sulfone, azo and azoxy bonded to the arene, the reaction occurs immediately and a wave resulting form oxidation of hexadienyl species is observed in the range 0-IV vs.SCE.Preparation of various hexadienyl compounds was achieved with good yields.In order to obtain ortho-substituted benzonitriles, electrochemical and chemical oxidations of hexadienyl complexes were compared.The best results were obtained with N-bromosuccinimide (NBS) and a demetallation generally occurs.A one-pot synthesis of benzonitrile compounds can be achieved after addition of cyanide ion and then NBS to a solution of (η⁵-cyclopentadienyl)(η⁶-arene) iron (1 +) in acetonitrile. 6-C6H5N(O)=NC6H4Cn-2>>⁺ is directly obtained from the azoxy dicationic compound <(CpFe)2(PhN(O)NPh)>²⁺.Keywords: Iron; Ferrocenes; Electrochemistry; Arene complexes; Oxidation