Optically active helical vinyl polymers via helix-sense-selective anionic polymerization of (S)-3-vinyl-2,2′-bis(methoxymethoxy)-1,1′-binaphthyl

- (S)-3-Vinyl-2,2′-bis(methoxymethoxy)-1,1′-binaphthyl 2 was synthesized and anionically polymerized.
- Poly-2 exhibited optical rotation as large as fourfold that of the monomer.
- The CD spectrum of poly-2 show intensive Cotton effects, implying the formation of main chain chirality, most probable helicity.
- The helical conformation of poly-2 was stable and insensitive to temperature variation.

A novel vinyl monomer, (S)-3-vinyl-2,2′-bis(methoxymethoxy)-1,1′-binaphthyl 2, was synthesized and underwent helix-sense-selective anionic polymerization to obtain helical polymers with an excess screw sense. The polymer ([α]36525 = −1610.0°) exhibited optical rotation as large as fourfold that of the monomer ([α]36525 = −356.0°). Poly-2 was confirmed to keep a prevailing helicity of backbone in solution by means of comparing the specific optical rotation, the CD and UV-vis spectra with that of monomer 2 and the model compound such as (S)-3-ethyl-2,2′-bis(methoxymethoxy)-1,1′-binaphthyl 3. The helical conformation of poly-2 was stable and insensitive to temperature variation. The excess value of one-handed helicity of poly-2 decreased with the increase of polymerization temperature.

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