Jj. Sepiol et J. Wilamowski, New aromatic rearrangement accompanying ring closure of 2-arylpropylidenemalonodinitriles to 1-aminonaphthalene-2-carbonitriles, TETRAHEDR L, 42(31), 2001, pp. 5287-5289
Cyclization and a rearrangement in concentrated sulfuric acid of 2-(4-subst
ituted-phenyl)propylidenemalonodinitriles (1) into 1-amino-4-methyl-6-subst
ituted-naphtalene-1-carbonitriles (5) appears to involve a series of steps
such as ipso electrophilic attack of the protonated nitrile function on the
para position of the phenyl group, opening of a spirobenzenium cation or i
ts transformation, and ring reclosure to the naphthalene framework with par
ticipation of the secondary alkyl carbocation as an active electrophile. (C
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