Synthesis and chiral recognition properties of poly(N‐propargylamide) gels derived from ornithine and lysine

Copolymerization of ornithine‐ and lysine‐derived N‐propargylamides, N‐α‐tert‐butoxycarbonyl‐N‐δ‐fluorenylmethoxycarbonyl‐L ‐ornithine N′‐propargylamide ( 1 ), N‐α‐tert‐butoxycarbonyl‐N‐ε‐fluorenylmethoxycarbonyl‐L ‐lysine N′‐propargylamide ( 2 ), N‐α‐fluorenylmethoxycarbonyl‐N‐δ‐tert‐butoxycarbonyl‐L ‐ornithine N′‐propargylamide ( 3 ), and N‐α‐fluorenylmethoxycarbonyl‐N‐ε‐tert‐butoxycarbonyl‐L ‐lysine N′‐propargylamide (4) with dipropargyl adipate was carried out using (nbd)Rh⁺η⁶‐C₆H₅B^?(C₆H₅)₃] as a catalyst in THF to obtain polymer gels in 80–93% yields. The gels adsorbed N‐benzyloxycarbonyl L ‐alanine, N‐benzyloxycarbonyl L ‐alanine methyl ester, and (S)‐(+)‐1‐phenyl‐1,2‐ethanediol preferably than the corresponding optical isomers. The order of chiral discrimination was poly( 1 ) > poly( 4 ) > poly( 2 ), poly( 3 ) gels. The fluorenylmethoxycarbonyl groups of the gels could be partly removed by piperidine treatment, leading to increase of adsorptivity but decrease of chiral recognition ability. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4175–4182, 2008