Abstract

The three new organometallic hydrazines [Fe(?5-Cp)(?6-RC6H4NHNH 2)]+PF6-, Cp=C5H5, R=H, [1]+PF6-; m-Me, [2]+PF6-; p-MeO, [3]+PF6-, were synthesised and characterised. They were obtained in CH2Cl2 by reaction of the hydrazine monohydrate, NH2NH2·H2O, with the corresponding precursors [Fe(?5-Cp)(?6-RC6H4Cl)] +PF6-. Similarly to free conventional organic hydrazines, the organometallic hydrazines [1]+PF6- and [3]+PF6- react with acetone affording hydrazones formulated as [Fe(?5-Cp)(?6-RC6H 4NHN=CMe2)]+PF6-, R=H, [6]+PF6-; p-MeO, [7]+PF6-. Likewise, the two other organometallic hydrazones containing the substituent groups R=0-Cl, [8]+PF6- and p-Me, [9]+PF6- were also obtained from their parent hydrazine precursors [4]+PF6- and [5]+PF6-, respectively. All the new compounds were characterised by elemental analysis and IR, UV - vis, 1H- and 13C-NMR spectroscopy. The crystalline and molecular structures of [1]+PF6- and [9]+PF6- were determined by single crystal X-ray crystallographic analysis. Both structures show a cyclohexadienyl-like character at the coordinated C6 ring of the phenylhydrazine and the p-methylphenylhydrazone with a folding angle of 6.0(5) and 7.1(6)°, respectively. © 2000 Elsevier Science S.A. All rights reserved.