Bifunctional thiourea-based organocatalyst promoted kinetic resolution polymerization of racemic lactide to isotactic polylactide.

Here, we prepared a series of thiourea-based organocatalysts 1-7 by combining two stereogenic elements: binaphthyl-amine and cyclohexyl diamine moieties. Catalyst ( R , S )-1 facilitated a stereoselective polymerization of rac -LA to afford iso-enriched PDLA with P m of 0.96 while its enantiomer ( S , R )-1 produced PLLA with P m of 0.96. These iso-enriched PLA contributed to forming a stereocomplexed PLA with a significantly increased T m of 196 °C.