Descriptors :
Step-growth polymerization,Bis-triazolinediones,Diels-Alder reaction,Ene reaction
Abstract :
In contrast to other electron deficient enophiles or dienophiles which react with 1,4-cyclohexadiene (1,4-CHD) under aromatization, 1,2,4-triazoline-3,5-diones react in a defined reaction sequence. In a first step the 1,4-cyclohexadinene reacts via an ene-reaction. The intermediately formed substituted 1,3-cyclohexadiene immediately reacts in a Diels-Alder reaction. The regiochemistry of the Diels-Alder reaction is controlled by the solvent polarity. This reaction sequence can be used to synthesize polymers. Low-molarmass model compounds were synthesized to elucidate the stereochemistry of the polymers. By varying the bistriazolinedione, polymers with backbones of different rigidity are available.
