Asymmetric induction in the cyclopolymerization of divinyl ethers derived from (R)‐ or (S)‐3,3′‐dimethyl‐1,1′‐bi‐2‐naphthol

Optically active divinyl ethers, (−)‐( R )‐ and (+)‐( S )‐2,2′‐bis[2‐(2‐vinyloxyethoxy)ethoxy]‐3,3′‐dimethyl‐1,1′‐binaphthyl [( R )‐ 1b and ( S )‐ 1b ] were polymerized to produce chiral poly(crown ether)s. Their optical rotation was found to be profoundly influenced by the polymerization conditions. When increasing the monomer concentration from 0,1 to 0,3 mol · 1 −1 , after polymerization with SnCl 4 in CH 2 Cl 2 at 0°C, the optical rotation of the resulting polymers is drastically changed from +44,5° to −17,3° for ( R )‐ 1b and from −35,6° to +20,9° for ( S )‐ 1b . The analysis of 1 H NMR showed that the polymers have changed their optical rotation due to a configuration which has a tendency to be preferentially racemic diad at higher monomer concentrations in a nonpolar solvent. There are indications that the twist of 2,2′‐binaphtyl moieties, the methyl groups in 3‐, and 3′‐positions as steric barrier, and the intramolecular solvation of the growing carbo‐cation cooperatively control the propagation to induce the asymmetry in the main chain.