A highly efficient domino protocol
has been developed for the synthesis
of 6-aryl-4-(methylthio/amine-1-yl)-2-oxo-2
H
-pyran-3-carbonitriles
and 4-aryl-2-(amine-1-yl)-5,6,7,8-tetrahydronaphthalene-1-carbonitriles
from simple and readily available α-aroylketene dithioacetals,
malononitrile, secondary amines, and cyclohexanone. This elegant domino
process involved consecutive addition–elimination, intramolecular
cyclization, and ring opening and closing sequences. Notably, in situ
generated 2-imino-4-(methylthio/amine-1-yl)-6-aryl-2
H
-pyran-3-carbonitrile plays multiple roles in the construction of
various novel polyaromatic hydrocarbons.