A chiral monomer N-[(R)--tert-butoxycarbonylbenzyl]methacrylamide ((R)-BCBMAM) was synthesized via amidation reaction between methacryloyl chloride and D-phenylglycine tert-butyl ester.Optically active polymers were prepared via free radical polymerization of ((R)-BCBMAM)initiated by AIBN at 60 ℃.In the presence of catalytic amount of trifluoroacetic acid
the tert-butyl of P(R-BCBMAM) was removed to obtain poly{N-[(R)--hydroxylcarbonylbenzyl]methacrylamide} P(R-CBMAM).1H-NMR
IR
CD and GPC were employmed to characterize the chemical structure of the products.The results indicated that the polymerization condition had slight effects on the chiroptical properties of P(R-BCBMAM).The results from specific optical rotation and circular dichroism spectra indicated that the P(R-CBMAM) and P(R-BCBMAM) had great difference in the chiroptical properties.On the basis of the results from circular dichroism (CD)
the optical activity of P(R-BCBMAM) was attributed not only to the chirality of amino acid side groups in monomeric units but also to the steric repulsion of tert-butyl groups.P(R-BCBMAM) and P(R-CBMAM) were coated onto silica gels as the chiral stationary phase (CSP) for high performance liquid chromatography (HPLC).The CSPs exhibit superior chiral recognition ability for some racemates.On the other hand
1H-NMR measurements of mixture of polymers and racemic 1
1'-bi-2-naphthol (BINOL) were conducted in chloroform-d.The characteristic hydroxyl proton signal of BINOL was split into two peaks ascribed respectively to the levo- and dextro-isomers.