ISSN:
0887-624X
Keywords:
stereoregular polymers
;
chiral polyamides
;
ω-amino acids
;
glycine
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Stereoregular, enantiomerically pure, chiral polyamides of the -AB- type, containing a natural (glycine) and a synthetic [(S)-5-amino-4-methoxypentanoic acid (AMP)] component have been prepared by the active ester polycondensation method. Thus, polyamide 7 was obtained by polycondensation of the conveniently activated H2NGly-AMPCO2R unit (6). In this reaction, 7 appeared accompanied by a considerable amount of cyclic (Gly-AMP)2 (8), which makes the isolation and purification of 7 difficult. The formation of cyclic byproducts could be avoided by preparing and polymerizing the oligoamide H2NGly-AMP-AMPCO2R (11), which has the terminal carboxyl group activated as the pentachlorophenyl ester. The resulting polyamide (12) was obtained in 85% yield and free of macrolactams, such as 8. The new polyamides 7 and 12 were characterized by elemental analysis and infrared and 1H- and 13C-nuclear magnetic resonance spectroscopies. Thermal studies revealed that 12 is crystalline and yields films with spherulitic texture by slow evaporation of formic acid solutions. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2741-2748, 1998
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
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