An amphiphilic manganese porphyrin-paired ionic copolymer: a highly efficient biphasic transfer catalyst for the selective oxidation of olefins with O2 and TBHP

Abstract

A novel amphiphilic manganese porphyrin-paired ionic copolymer, {ADA-INA-[Mn(TPPS)(OAc)]}_n, was prepared by the self-assembly process of non-cross-linked amphiphilic polymeric ligands with inorganic species. Thus, {ADA-INA-[Mn(TPPS)(OAc)]}_n was prepared from Mn(TPPS)(OAc) and poly{[3-(acryloylamino)propyl]dodecyldimethylammonium nitrate}-co-{(N-isopropylacrylamide)₁₂}. The physicochemical properties of the synthesized catalyst were characterized by FT-IR, SEM and UV-vis spectroscopy. The compound {ADA-INA-[Mn(TPPS)(OAc)]}_n showed the capability of catalyzing the oxidation of olefins in solid–liquid biphasic reaction systems with high catalytic activity and selectivity. The oxidation of styrene, α-methylstyrene, cis-cyclooctene, 1-octene and 1-decene, catalyzed by the reaction-controlled phase transfer catalyst {ADA-INA-[Mn(TPPS)(OAc)]}_n using O₂ and TBHP in a biphasic medium was investigated. After the catalytic reaction, in the solid–liquid biphasic system, the catalyst could be conveniently recovered and steadily reused without a change in the catalyst structure. The unique amphiphilic catalyst structure was revealed to be responsible for the catalyst's excellent performance in the oxidation of olefins with O₂ and TBHP by accelerating the mass transfer.