Heterogeneous catalysis of novel polymeric rare earth complexes under solvent-free conditions: Zero-emission synthesis of β-amino alcohols

Novel polymeric rare earth complexes, RE₂(BPDS)₃ (RE = rare earth metal, BPDS = biphenyl-4,4′-disulfonate), in which the metal ions are homogeneously dispersed, were synthesized by the self-organization of the metal ion and the corresponding aryldisulfonate and successfully used as a reusable Lewis acid catalyst for the ring-opening reaction of epoxides with amines to give the desired β-amino alcohols in excellent yields under solvent-free heterogeneous conditions. The catalysts can be quantitatively recovered and reused more than five times without decreasing their activities. The catalytic activity of Sc(OPf)₃ (Pf = SO₂C ₈F₁₇) for the same reaction under solvent-free conditions was also examined.