Novel isocyanide-based four-component reaction: a facile synthesis of fully substituted 3,4-dihydrocoumarin derivatives.

A novel isocyanide-based four-component reaction between a 2-hydroxybenzaldehyde, Meldrum's acid, an isocyanide, and an aromatic or an aliphatic alcohol efficiently provide 3,4-dihydrocoumarin derivatives in good to excellent yields without using any catalyst or activation. The reaction can be carried out as a simple one-pot protocol at room temperature.