Highly active zinc alkyl cations for the controlled and immortal ring-opening polymerization of epsilon-caprolactone

Zinc alkyl cations supported by N,N-BIAN-type bidentate ligands were found to be highly active in the immortal ROP of epsilon-caprolactone to yield narrowly disperse and chain length-controlled poly(epsilon-caprolactone), whether in solution or bulk polymerization conditions.