Cross-linked poly(4-vinylpyridine/styrene) copolymers as a support for immobilization of ytterbium triflate

Eight cross-linked poly(4-vinylpyridine/styrene) (P/S) resins (as beads) were prepared by radical suspension polymerization. Ytterbium triflate was immobilized in the range of 0.10–0.24 mmol/g by mixing with the P/S resins. The ytterbium triflate-immobilized P/S resins exhibited good activity in two Lewis acid-catalyzed reactions. Low pyridine containing resins were recycled with no loss of activity, while a slight loss of activity was observed with the higher pyridine containing resins.