Polymerizations and polymers of quinonoid monomers

Asymmetric anionic polymerization of 7-cyano-7-phenyl-1,4-benzoquinone methide

“…Asymmetric anionic polymerization of 3 with a i PrPhOLi/(-)-Sp initiator Previously, we carried out asymmetric anionic polymerization of 1 with the i PrPhOLi/(-)-Sp initiator in a mixture solution of dichloromethane/toluene (30/70 in vol%), and we obtained optically active polymer with a negative specific rotation value ([a] 435 = -5.9°) though it was small [16,18]. This indicates that an optically active polymer can be obtained from a prochiral quinone methide monomer by asymmetric anionic polymerization, that is, that the configuration of stereocenters created in the main chain is biased to either R or S through the asymmetric anionic polymerization process.…”

“…However, introduction of electron-accepting and/or electron-donating substituents on the exomethylene carbon of the QM reduces its reactivity, leading to isolable monomers as crystals at room temperature: e.g., 7,7-dicyano-1,4-benzoquinone methide [10], 7-(alkoxycarbonyl)-7-cyano-1,4-benzoquinone methides [11], 7,7-bis(alkoxycarbonyl)-1,4-benzoquinone methides [12], 7,7-diphenyl-1,4-benzoquinone methide [13], 4-(1 0 ,3 0 -dithiolan-2 0 -ylidene)-2,5-cyclohexanedien-1-one [14], and 2,6-dimethyl-7-phenyl-1,4-benzoquinone methide [15]. The polymerization behaviors of these isolable QMs have been investigated, and it was found that the radical and anionic polymerizations of QMs take place between the substituted exomethylene carbon atom and exocarbonyl oxygen with formation of stable aromatic structure to afford the polymers, poly(oxy-1,4-phenylene-substituted methylene)s [11,12,15,16]. As QMs having two different substituents on the exomethylene carbon are regarded as prochiral monomers, many asymmetric carbons might be generated in the main chain of the polymers through the polymerization process.…”

Polymerization by Insertion of Molecular Oxygen into Crystals of 7,7,8,8‐Tetrakis(ethoxycarbonyl)quinodimethane

“…The changes in the IR spectrum observed in the solid-state polymerization of 1 lend support to the proposition that this reaction follows the conventional mode observed for substituted quinodimethane molecules: the polymerization takes place at the disubstituted exomethylene carbon atoms with formation of the corresponding stable aromatic structure. [13] The 1 H NMR peak at d = 7.53 ppm assigned to the phenylene protons of the polymer obtained by the thermal solid-state polymerization was observed at a lower field than the corresponding one (d = 6.70 ppm) of the polymer obtained by the solution polymerization. In the 13 C NMR spectrum the peak at d = 89.4 ppm assigned to the quaternary carbon atom in the solid-state polymerization polymer was observed 19 ppm further downfield than the corresponding signal (d = 70.0 ppm) in the solution-phase polymerization polymer (Figure 1).…”

Polymerization of chloro-p-xylylenes, quantum-chemical study

“…The reactivity of chloro-substituted p-xylylenes decreases as the number of chlorine substituents is increased [30]. The p-xylylene is stable only in the gas phase or in a very dilute solution at a very low temperature.…”