Synthesis and Polymerization Behavior of New Monomers based on Highly Conjugated Quinoid Structure

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7-Alkoxycarbonyl-7,8,8-tricyanoquinodimethanes, 7,7-bis (alkoxycarbonyl), 8,8-dicyanoquinodimethanes, and 7,8-bis (benzyloxycarbonyl)-7,8 cicyanoquinodimethane were synthesized successfully as isolable crystals at room temperature. 7,7 Bis (alkoxycarbonyl)-8,8-dicyanoquinodimethane with meldrum acid unit at the exocyclic position had same electron-accepting property to 7,7,8,8-tetracyanoquinodimethane and copolymerized with styrene in an alternating fashion. Homopolymer of 7,8-bis (benzyloxycarbonyl)-7,8-cicyanoquinodimethane was photodegaradable due to existence of phenyl groups.7-Alkoxycarbonyl-7-cicyanobenzoquinone methides and 7-cyano-7(phenyl)benzoquinone methide were synthesized successfully as isolate crystals at room temperature. It was concluded that polymerizability of 7-Alkoxycarbonyl-7-cicyanobenzoquinone methides depends significantly on the steric effect of the alkoxy groups. Spontaneous polymerization mechanism of 7-cyano-7-(phenyl)benzoquinone with styrene could be explained well by both diradical intermediate formation in the initiation step by the bond-forming initiation mechanism and chain addition like a conventional radical copolymerization in the propagation step.1,4-Dicarbonyl-1,4-dihydronaphthalene generated in situ in a degassed benzene copolymerized with benzoquinones and benzoquinone diimines spontaneously and alternatingly to give aromatic polyesters and polyamides, respectively.2,5-Bis(dicyanomethylene)-2,5-dihydrofuran, 2,5-dimethylene-2,5-dihydrothieno[3,2-b]thiophenes, and 2,5-bis(1.3-dithiolan-2-ylidene)-2,5-dihydrothiopene were synthesized successfully as isolable crystals at room temperature. It was pointed out that polymerizability depends significantly on the energy difference between benzenoid structure and quinonoid structure. Polymerization of 2,5-Bis(1.3-dithiolan-2-ylidene)-2,5-dihydrothiophene was found to be driven by both release of ring strain energy and aromatization energy.