An unprecedented organocatalytic three-component domino Knoevenagel/vinylogous Michael reaction starting from simple enolizable aldehydes, malononitrile, and nitroolefins is reported. This facile two-step domino process provides a straightforward stereoselective route to multifunctional vinyl malononitrile products (up to 82 % yield, 85:15 d.r.) containing a nitroalkane moiety, and contributes to the development of sustainability and atom economy. The application of the obtained domino products for synthesis of highly functionalized o-terphenyls (of high interest for materials science and medicinal chemistry) through subsequent new three-step domino reaction involving cyclization-tautomerization-aromatization steps, has been demonstrated.
Keywords: Knoevenagel reaction; Michael addition; domino reactions; multicomponent reactions; o-terphenyls; organocatalysis.
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