Conformational studies of optically active poly(oxyisobutylidenecarbonyl) [poly(L‐α‐hydroxyisovaleric acid)] and its oligomers

Optical rotatory dispersion (ORD) and circular dichroism (CD) of poly(oxyisobutylidenecarbonyl) (II) were investigated and compared with those of its optically active oligomers (III). The two‐term DRUDE equation was applied to analyze the ORD curves using n‐π * ‐ and π‐π * ‐transition bands as the critical wavelengths, λ 0 and λ 1 , respectively. No drastic difference in ORD curves between the polymer and oligomers was detected in chloroform, which suggests that the polymer has no special conformation. On the other hand, in dioxane and acetonitrile λ 1 of the polymer II shows a red shift in comparison with that of its oligomers.