Heterotrinuclear Ring Opening Copolymerization Catalysis: Structure–activity Relationships

Heteronuclear complexes are highly active catalysts in alternating ring opening copolymerizations (ROCOP) of cyclohexene oxide (CHO)/carbon dioxide or CHO/phthalic anhydride (PA). In this contribution, a series new trinuclear is investigated through structure activity study that reveals the influences ligand electronic properties and metal selection over catalytic linkage selectivity. The fastest catalyst shows high for CHO/CO2 ROCOP at low pressure (1 bar CO2 pressure) features coordinated to two Zn(II) centers with inexpensive abundant Na(I) (TOF = 1084 h–1, catalyst/CHO 1:4000, 1 bar, 100 °C). High CHO/PA copolymerization achieved combination Mg(II) one center 142 catalyst/PA/CHO 1:200:4000, °C); further undergoes “switchable” epoxide/anhydride epoxide polymerization (ROP), allowing controlled polyether block formation. Polymerization kinetic investigations reveal electronics, complex stability metal–metal separation, their retention throughout catalysis. findings should help guiding future design, facilitate polymer production, inspire other utilization processes.