Diamidoamine Aluminum Complex as Effective Initiator for Random Copolymerization of Substituted Carbonate with L-Lactide

Designing a catalyst for random copolymerization by ring-opening polymerization (ROP) is an actual task. In the present work, we report the synthesis of aluminum complexes (R′ = Et, R′′ = Ph (5); R′ = Bn, R′′ = Ph (6); R′ = t-Bu, R′′ = Ph (7); R′ = R′′ = Ph (8)] based on diamidoamine pro-ligands. The reactivity of complexes in the ROP of ε-caprolactone (ε-CL) was studied. The highest activity was shown by complexes 5 and 8, containing phenyl groups at the terminal nitrogen atoms of the ligand in the ROP of ε-CL. Also, complex 5 was an effective initiator of copolymerization of 2-(benzyloxycarbonyl)-2-methyltrimethylene carbonate (TMC_R) and L-lactide (L-LA) which led to the formation of a random copolymer.