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Optically active 4-alkyl-2-(3,5-diiodophenyl)oxazoline was synthesized and polymerized by the Sonogashira–Hagihara coupling reaction to obtain the poly(phenylene-ethylnylene)s bearing oxazoline derivatives with number-average molecular weight ranging from 1060 to 17 300 in 40–72% yields. All the polymers exhibited higher values of specific rotation ([α]_D=+41.6 to +83.7°) than the monomer ([α]_D=−1.2 to −16.9°). On the basis of the results of specific rotation, circular dichroism and ultraviolet analyses, the optical activities of the polymers arise from not only the configurational chirality of the optically active oxazoline pendant groups but also the higher-order structure such as helical conformation.

Chiral and achiral amine-functionalized norbornene monomers were synthesized and polymerized using 1st Grubbs Catalyst, and the chiroptical properties of the polymers were studied. The tendency to increase the absolute value of specific rotation with an increase in M_n was observed. Using (−)-spartaine (Sp) as a chiral additive, the chiroptical property of the obtained polymer was enhanced in some cases.

Asymmetric anionic homopolymerizations of (S)-(–)-N-maleoyl-L-leucine-aza-15-crown-5 ((S)-A15C5LMI) and (S)-(–)-N-maleoyl-L-phenylalanine-aza-15-crown-5 ((S)-A15C5PAMI) were carried out with chiral anionic initiator consisting of organometal and chiral ligand to obtain optically active polymers. Chiroptical properties and structures of the polymers obtained were analyzed by circular dichroism, ultraviolet, nuclear magnetic resonance and gel permeation chromatography measurements. The additional effects of (R)-cyclohexylethylamine (to the obtained poly((S)-A15C5LMI) were investigated.

Asymmetric anionic homopolymerizations of N-4′-benzo 15-crown-5 maleimide (B15C5MI) were carried out with a chiral anionic initiator consisting of organometal and chiral ligand to obtain optically active polymers. Chiroptical properties and structures of the polymers obtained were analyzed by CD, UV, NMR and gel permeation chromatography measurements. The additional effects of (R)-cyclohexylethylamine ((R)-Cyc) to the obtained poly(B15C5MI) were investigated.

Seven novel types of acetylene monomers (PSRs) having a 4′-substituted phenyl moiety or 4′-substituted biphenyl moiety as a pendant group were synthesized from 4-oxo-4-(prop-2-ynyloxy)butanoic acid with phenol derivatives, and polymerized with the rhodium-catalyzed system. All four PSRs having 4′-substituted biphenyl moiety as a pendant group showed a liquid crystalline phase and two of these polymers showed a nematic phase.

π-Conjugated polymers attract attention from showing not only an interesting electric and optical property but also workability. The random co-oligomers with N-cyclohexylmaleimide and N-substituted carbazole in the main chain were carried out by Yamamoto coupling reaction. The co-oligomers showed the fluorescence color of red from blue. Especially, when 2,7-dibromo-N-hexylcarbazole was used as the monomer, the fluorescence color of the resulting co-oligomer changed from magenta to blue by the difference of polarity of solvent.

Coupling polymerizations of 2,3-dibromo-N-substituted maleimide (DBrRMI) (R=benzyl (DBrBnMI), phenyl (N-phenyl-2,3-dibromomaleimide (DbrPhMI)), cyclohexyl (N-cyclohexyl-2,3-dibromomaleimide), n-hexyl (N-n-hexyl-2,3-dibromomaleimide) and n-dodecyl (N-n-Dodecyl-2,3-dibromomaleimide, DBrDMI)) were carried out using palladium or nickel catalysts. Number-average molecular weights (M_n) of poly(RMI-alt-Ph) or poly(RMI-alt-TP) obtained by Suzuki–Miyaura cross-coupling polymerizations of DBrRMI with benzene-1,4-boronic acid (PhDB) or 2,5-thiophene diboronic acid (TPDB) were 680–1270 by GPC analyses. In contrast, coupling polymerizations of DBrRMI with 1,4-diiodobenzene gave random poly(RMI-co-Ph). Poly(RMI-co-Ph)s exhibited higher thermal stability than monomer and poly(RMI-alt-Ph). Copolymers showed strong photoluminescence from yellow to light blue color in THF.

Chiral itaconimides bearing amino-acid esters at side chain (MRII), such as phenylglycine-, phenylalanine- and leucine-methyl ester, were polymerized with organometal-chiral ligand complexes to obtain optically active polymers. The effects of the polymerization conditions on the optical activity and structure of poly(MRII)s were investigated with gel permeation chromatography, circular dichroism, specific rotation and ¹³C nuclear magnetic resonance measurements.