First example of the topochemical polymerization of the (E,E)-muconic acid derivative

The 1-naphthylmethylammonium salts of not only (Z,Z)- but also (E,E)-muconic acid were found to polymerize upon photoirradiation in the crystalline state to provide a stereoregular polymer in a high yield. The stereochemical structure of both polymers obtained from the monomers with different configurations was identical, i. e., a meso-diisotactic-trans-2,5-structure. The stereochemistry of the polymers obtained is discussed on the basis of the monomer configuration and the molecular packing in the crystals.