Efficient synthesis of benzo[g]-and benzo[h]chromene derivatives by one-pot three-component condensation of aromatic aldehydes with active methylene compounds and naphthols

A convenient procedure is reported for the synthesis of benzo[ g ]-and benzo[ h ]chromene derivatives via one-pot three-component condensation of aromatic aldehydes with malononitrile or ethyl cyanoacetate and 1-or 2-naphthol in the presence of 10 mol % of titanium tetrachloride as catalyst. The reactions require no solvent; they are characterized by simple experimental procedure and easy isolation and can be performed on enlarged scale.