POLYMERIZABLE MESOIONS .2. RADICAL POLYMERIZATION AND 1,4-DIPOLAR POLYCYCLOADDITION OF A 4-VINYLPHENYL-MODIFIED MESOIONIC 4,6-DIOXO-1,3-DIAZINE

Mesoionic l-4,6-dioxo-3-phenyl-1-(4-vinylphenyl)-1,3-diazine (5) was o btained by condensation of 3-phenyl-1-(4-vinylphenyl)formamidine (3) w ith methylmalonic acid (4). This vinyl-substituted mesoionic heterocyc lic compound was polymerized by usual radical initiation and, addition ally, by thermally controlled polycycloaddition in solution, yielding two different types of polymers, 6, 7. According to the X-ray diffract ion analysis, the structure of a low molecular weight model proves the regioselectivity of the polycycloaddition.