Antioxidants and stabilizers, 107. Reaction of N-phenyl-1,4-benzoquinoneimine with the 1-cyano-1-methylethyl-radical

The reaction of N-phenyl-1,4-benzoquinoneimine (I)

1 Decoding of abbreviations see p. 103/104.

and 4-hydroxydiphenylamine (II) with the carbon centred 1-cyano-1-methylethyl radical (R^·) was studied in connection with an investigation of the action mechanism of industrial antidegradants, such as N-phenyl-N′-sec-alkyl-1,4-phenylenediamines. The mixture of I and II reacts very readily with R^·, giving rise to III , VI , and VIII . I alone reacts much slowlier, and the reaction mixture contains more products. IV and VII were identified along with III . Under the conditions used, II alone does not react at all. IV exists in two isomeric forms, syn and anti. VIII is very labile; XI was isolated from its transformation products. Reduction of IV gives V , which is labile, similarly to VIII .