The Conformations and ¹H-NMR Chemical Shifts of 1, 1′-Bis(chlorinatedphenyl)ferrocenes

Abstract

The dipole moments were measured for 1, 1′-bis(4-chlorophenyl)-, 1, 1′-bis(4-chloro-2methylpheny1)- and 1, 1′-bis(3, 5-dichlorophenyl) ferrocene.1, 1′-Bis(4-chlorophenyl)ferrocene was concluded to be an equivalent mixture of five antiprismatic conformers, but on the other compounds, the rotation of cyclopentadienyl rings was considerably restricted. For example, the intramolecular repulsion between the substituents was recognized on 1, 1′-bis(4-chloro-2methylphenyl) ferrocene, whereas the attractive force was induced on 1, 1′-bis(3, 5-dichlorophenyl)ferrocene. Further, the relation between the conformation and the proton chemical shift values was also discussed.