Optical rotatory studies of poly(R)(‐)‐3.7‐dimethyloctene‐1 and its model compound

We have prepared optically active (R)(—)‐3,7‐dimethyloctene‐1 from (R)(+)‐citronellyl acetate by hydrogenation followed by pyrolysis. The polymerization was carried out using a catalyst derived from lithium aluminum hydride, monomer and titanium tetrachloride in dry benzene. We then studied the optical rotatory properties of the resulting poly(R)(—)‐3,7‐dimethyloctene‐1 and the model compound of this polymer and found an optical activity enhancement of the former over the latter. However, the rotatory dispersions for polymer and model compound fit one term DRUDE equations with the same λc. We explain these results in terms of the rigid spatial requirements of the polymer structure which lead to a preference of certain configurations and conformations for short segments of the polymer chain.