Conformational Studies of Dicyclohexylthallium Chloride, Bis(4-methylcyclohexyl)thallium Chloride and Bis(4-tert-butylcyclohexyl)thallium Chloride by (1)H NMR

Article abstract of DOI:10.1002/mrc.1270221207

Vicinal thallium-hydrogen coupling constants are used to discuss conformations in dicyclohexylthallium chloride, bis(4-methylcyclohexyl)thallium chloride and bis(4-tert-butylcyclohexyl)thallium chloride.Thallium does not have a very strong preference for equatorial positions in dicyclohexylthallium chloride, whereas bis(4-alkylcyclohexyl)thallium chlorides exist largely in one conformation.Bis(4-methylcyclohexyl)thallium chloride exists in three isomeric forms; the major product appears to be the cis-isomer (equatorial methyl, axial thallium), with the other twoisomers probably containing thallium trans to the methyl group (axial thallium being preferred).The preference for the cis-isomer (equatorial tert-butyl, axial thallium) of bis(4-tert-butylcyclohexyl)thallium chloride is such that other isomers are not obtained.