Benzene optically active monomer

The H and 13C NMR spectra of azo compounds incorporated into monomers and polymers have been measured.67-73 Chiral methacrylic polymers containing azobenzene chromophore,67,68 epoxy-based polymers functionalized with tricyanivinylphenylazo chromophores,69 4-vinylazobenzene and homo- and copolymers,70 microstructure of trans-4-acrylooyloxyazo-benzene/methyl methacrylate copolymers,71 optically active poly[(S)-4-(2-methacryloyloxypropanoyloxy)azobenzene]72 and polyetherurethane pendant with azo dye by TV-substitution73 have been studied. 

In 1962, Inoue et al [140, 141], first succeeded in carrying out an asymmetric selective polymerization of /-propylene oxide (J,/-PO) using dialkylzinc-optically active (+)-borneol or (-)-menthol catalysts with a conversion of 30% (Scheme LVIII) the polymer was found to be optically active, levorotatory in benzene solution and dextrorotatory in chloroform, like the polymer obtained by Price [92] from the purified /-enantiomer monomer. There were no absorption bands corresponding to the original alcohol detected in the IR spectrum and the optical activity of the polymer must, therefore, be attributed to the prevalence of one of the two enantiomeric units. 

In the subsequent work the debenzylation of )3-benzylmercapto-a-substituted-propionyl chlorides with two moles of aluminum halide was proved to be a general and very convenient method for the preparation of optically active a-substituted-j3-thiolactones, and a series of optically pure j3-thiolactones was prepared by the debenzylation method. Debenzylation was performed at room temperature in the presence of a benzene solution of aluminum bromide. Monomers were obtained in a yield of 40—70% as shown in Table I. 

In relation to poly(propylene oxide) various kind of heterocyclic monomers and their polymers were investigated. Poly(styrene oxide) and its ether derivative show little change in different solvents. As an optically active model compound of poly(styrene oxide), (+)-l,2-diethoxy-1-phenyl ethane was synthesized. The ORD curves measured in benzene, chloroform, hexane and neat are all simple curves and are almost the same, as shown in Figure 7. 

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