The chemistry of 1,3,5-triazacyclohexane complexes. Part 10. New sandwich complexes of praseodymium(III) containing triazacyclohexane ligands

N-substituted 1,3,5-triazacyclohexanes (R(3)TAC) react with praseodymium trifluoromethane sulfonates [Pr(OTf)(3)] to give the corresponding complexes, containing one or two R(3)TAC ring(s) coordinated to praseodymium, depending on R. The crystal and molecular structures of these compounds have been determined by X-ray diffraction. The complex containing two coordinated R(3)TAC is mononuclear, while the complex containing one R(3)TAC is dinuclear with three triflate bridges. NMR diffusion studies indicate that these structures also occur in benzene solution.