Transmetallation reaction of cyclomercurated anils of benzoylferrocene with metallic tin.: X-ray crystal structure of [SnCl2{(η5-C5H5)Fe(η5-C5H3CPh=NC6H4-4-CH3)}2]

The transmetallation reaction of cyclomercurated anils of benzoylferrocene [HgCl{(eta(5)-C5H5)Fe(eta(5)-C5H3CPh=NAr)}] (Ar = substituted phenyl groups) with metallic tin was carried out in refluxing xylene to give dichlorobisferrocenyltin(IV) [SnCl2{(eta(5)-C5H5)Fe(eta(5)-C5H3CPh=NAr)}(2)]. The composition and structure of products were characterized by elemental analysis, IR, H-1-NMR and 2D NOESY spectra. The molecular structure of [SnCl2{(eta(5)-C5H5)Fe(eta(5)-C5H3CPh = NC6H4-4-CH3)}2] was determined by single crystal X-ray analysis. The distances of N and Sn are 2.519(3) and 2.501(3) Angstrom, respectively, shorter than the sum of van der Waals radii of N and Sn (3.6 Angstrom), indicating an intramolecular coordination of N and Sn. The Sn-119-NMR spectra were recorded, and a satisfactory linear relationship was found to exist between the Sn-119 shifts (delta) and Hammett substituent constants. (C) 1998 Elsevier Science S.A. All rights reserved.