3-Ferrocene-substituted 3-mercaptopropenales and their schiff bases as ligands for transition metal complexes

Article abstract of DOI:10.1016/s0020-1693(97)05892-1

Nucleophilic substitution of chlorine by sulphur in 3-ferrocenyl-3-chloropropenale and 1,1′-bis(3-chloropropenale)ferrocene yields the air-sensitive 3-ferrocenyl-3-mercaptopropenale and the 1,1′-bis(3-mercaptopropenale) ferrocene, respectively. These compounds form stable neutral chelates with zinc(II), nickel(II), cobalt(II) and copper(II). Their Schiff bases with aniline or primary diamines, obtained by direct reaction of the free 3-ferrocene-substituted 3-mercaptopropenales or by reaction with their transition metal chelates, are excellent ligands for electron-rich transition metals. The X-ray structure determination of bis (β-ferrocenyl-β-mercapto-N-phenyl-vinylaldiminato) nickel (II) indicates S,O coordination and cis arrangement of the ligands. The coordination sphere is distorted tetrahedrally. Cyclic voltammetry reveals only a slight influence of the bound transition metal on the electron density within the ferrocene subunit.