The photoreaction behaviors of various muconic derivatives, dialkyl (
Z, Z)-muconates (1),
N, N'-dialkyl-(
Z, Z)-muconamides (2), and di(alkylammonium) (
Z, Z)-muconates (3) in the crystalline state were investigated. The crystals of these compounds provided the corresponding (
E, E)-isomers or tritactic polymers as the photoproducts during irradiation using a high-pressure mercury lamp, depending on the structure of alkyl substituents. The isomerization and polymerization were revealed to proceed via a crystal-to-crystal process based on the powder X-ray diffraction. The ammonium derivatives with higher
n-alkyl substituents were found to have a high polymerization reactivity to yield a polymer with a
meso-diisotactic-
trans-2, 5-structure and high molecular weight, similar to the polymerization of the previously reported diethyl ester.
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