Binaphthol propylene polymerization

Propylene sulfide can be resolved more efficiently by using a mixture of diethylzinc and (S)-binaphthol (179). The polymerization affords, at 67% conversion, unreacted monomer, [a]D25 +51.8°, in 92% ee, together with optically active polymer, [a]D25 —103°. 

Propylene sulfide (174) can also be polymerized enantiomer-selectively [252-262], In the polymerization with a ZnEt2-(-)-binaphthol initiator system at room temperature, the... 

Propylene sulfide (291) can also be polymerized enantiomer-selectively with optically active initiators. The enantiomer selectivity is generally higher than that in the polymerization of 286, and especially high electivity has been reported for polymerization with the ZnEt2/(S)-(-)-2,2 -binaphthol initiator system the ratio of (S)-monomer consumption rate to (P)-monomer consumption rate ( sAr) was 20 at room temperature. 

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