Polymer, Vol.44, No.24, 7377-7381, 2003
Synthesis of poly (1,4-naphthylene) bearing crown ether side chain by asymmetric oxidative coupling polymerization
The oxidative coupling polymerization of racemic-, (R)-, and (S)-2,2',3,3'-tetrahydroxy-1,1'-binaphthyl derivatives bearing a crown ether moiety was carried out in the presence of a Cu(I) or Cu(II) catalyst with various ligands, such as N,N,N',N'-tetramethylethylenediamine, (S)(+)-1-(2-pyrrolidinylmethyl)pyrrolidine, (-)-sparteine [(-)Sp], and (S)-(-)-2,2'-isopropylidenebis(4-phenyl-2-oxazoline). Methanol-insoluble poly(binaphthyl crown ether) with a molecular weight up to M-n = 4.1 x 10(3) was synthesized in moderate yields. Polymerization using (-)Sp proceeded in an S-selective manner; the polymer with the highest negative specific rotation was obtained with the (S)-monomer. The obtained polymers exhibited characteristic abilities for chiral recognition toward amino acids, such as 2-phenylglycine hydrochloride and 2-phenylglycine methyl ester hydrochloride. (C) 2003 Elsevier Ltd. All rights reserved.