THE THERMAL-DECOMPOSITION OF STYRENE-CO-ACRYLONITRILE TRIMERS TO FORM 2-AMINO-3-METHYL-1-NAPHTHALENECARBONITRILE

During the spontaneous copolymerization of styrene and acrylonitrile, many different trimer structures are formed. Some of the trimers contain two acrylonitrile units and one styrene unit (An2S). These trimers are composed of three pairs of cis-trans diastereomers, all having a 1-substituted-4-cyanotetralin nucleus. Two of the cis-trans pairs have been found to decompose upon heating resulting in the formation of 2-amino-3-methyl-1-naphthalenecarbonitrile. The mechanism of this rearrangement involves the elimination of ethylene via a retro Diels-Alder reaction. Kinetic investigations show that the reaction is first order in An2S trimer.