Crystal Structure and Corrosion Inhibition Properties of Ferrocenyl- and Phenylendiamine-Iminomethylphenoxy Cobalt Complexes

Abstract

Abstract: The crystal structures of bis[2-(ferrocenyl-iminomethyl)phenoxy]cobalt(II) (CoII(L)2) [monoclinic, a = 12.5466(3) Å, b = 10.6782(3) Å, c = 21.2695(6) Å, α = γ = 90°, β = 92.944(2)°, V = 2845.82(13) Å3, Z = 4, space group P21/c] and bis(2-[(4-dimethylamino-phenylimino)-methyl]-phenoxy) cobalt (II) (CoII(M)2) [triclinic, a = 10.2916(4) Å, b = 16.4867(10) Å, c = 17.6782(11) Å, α = 114.754(2)°, β = 96.614(4)°, γ = 97.736(4), Z = 4, space group P-1] dominated by extensive hydrogen bonding such as O–H···N, N–H···O and N–H···N interactions. In both structures the central CoII is displaying a slightly distorted tetrahedral coordination sphere involving two iminoethyl-phenoxy ligands. The inhibition efficiency of the Co complexes concerning the corrosion of mild steel in acidic solution has been investigated by electrochemical impedance spectroscopy. Graphical Abstract: The crystal structures of two bis(iminomethylphenoxy) cobalt complexes containing respectively a ferrocenyl and a phenylendiamine group are described. First results on their inhibition properties concerning the corrosion of mild steel in hydrochloric acid are reported and discussed. [Figure not available: see fulltext.]