| We obtained novel chiral N-propargylphosphonamidate monomers with P-chiral center by condensation twice (HC≡CCH2NH(P=O)R1R2. a4: R1=CH3, R2=NHC(CH3)3 a6: R1=CH3, R2=NHC6H11 a9: R1=OPh, R2 =NHC(CH3)3. a10: R1=OPh, R2=NHC6H11). The diastereomer monomers were successfully isolated from the other ones by the column chromatography with ethyl acetate and methanol as effluent, and the analysis of 31H-NMR and 31P-NMR spectroscopy proved the separation of the isomers. In addition, P-achirality monomer (a1:HC=CCH2NHP=O(OPh)2) was synthesized by the same method. Polymerization and copolymerization were carried out with (nbd)Rh+[η6-C6H5B-(C6H5)3] as a catalyst in CHCl3 giving the polymers with yields at 48%-92% and number-average molecular weights of 1300-38160. CD and UV-vis spectroscopies indicating that the polymers took a helical structure with predominantly one-handed screw sense because of P-chiral center solely contribution. We studied the other factors such as solutions, temperature, the content of MeOH, and got the conclusion that with the decrease of solution's polarity, the rise of temperture and the content of MeOH would result the helical structure transferred into a random coil to some extent, which proved that P-chirality have effect on the helical structure again.
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