Guangzheng Gao, F. Sanda, T. Masuda
May 8, 2003
Citations
0
Influential Citations
110
Citations
Quality indicators
Journal
Macromolecules
Abstract
The present study deals with the synthesis and polymerization of novel amino acid-derived acetylene monomers, N-(tert-butoxycarbonyl)-l-alanine N‘-propargylamide (L-1A), N-(tert-butoxycarbonyl)-l-alanine N‘-methyl-N‘-propargylamide (N-Me-L-1A), and N-(tert-butoxycarbonyl)-l-alanine propargyl ester (L-1E) and the analysis of the properties of the formed polymers. The monomers were synthesized by the condensation of N-(tert-butoxycarbonyl)-l-alanine with propargylamine, N-methylpropargylamine, and propargyl alcohol in 50, 89, and 72% yields, respectively. They satisfactorily underwent polymerization with (nbd)Rh+[η6-C6H5B-(C6H5)3] as a catalyst ([M]0/[Cat] = 10−200) in THF and CH2Cl2 at 0−50 °C to afford the corresponding polymers with Mn's in the range 1 × 104−2 × 105. Poly(L-1A) exhibited a large specific rotation {[α]D = −1349° (CH2Cl2)} and a CD signal ([θ]max = −3.2 × 104 deg cm2 dmol-1 (CHCl3), suggesting that it takes a helical conformation. On the other hand, poly(N-Me-1A) and poly(L-1E) showed no e...