Ring-opening metathesis polymerization of amino acid-functionalized norbornene derivatives

Amino acid-derived novel norbornene derivatives, N,N '-(endo-bicyclo[2.2.1] hept-5-en-2,3-diyldicarbonyl) bis-L-alanine methyl ester (NBA), N, N '-(endo-bicyclo[2.2.1] hept-5-en-2,3-diyldicarbonyl) bis-L-leucine methyl ester (NBL), N,N '-(endo-bicyclo[2.2.1] hept-5-en-2,3-diyldicarbonyl) bis-L-phenylalanine methyl ester (NBF) were synthesized and polymerized using the Grubbs 2nd generation ruthenium (Ru) catalyst. Although NBA, NBL, and NBF did not undergo homopolymerization, they underwent copolymerization with norbornene (NB) to give the copolymers with M. ranging from 5200 to 38,100. The maximum incorporation ratio of the amino acid-based unit was 9%, and the cis contents of the main chain were 54-66%. (c) 2006 Wiley Periodicals, Inc.