If you mention exactly what type of chromone you want it will be helpful to give any suggestion.

You may try with beta-keto ester, cyclic 1,3-diketone and aldehyde (preferrably aromatic) in presence of lewis acid under solvent-free condition. In that case you get 4-H chromene-4-one.

Chopra,

You can prepare this compound starting by 2-hydroxyacetophenone and ethyl formate as reported

---Fernando Rodríguez-Ramos et al., Bioorganic Chemistry 50 (2013) 17–25.

Good luck

Cyclic diketone reacted with aryl aldehyde using acid catalyst to give chromen-4-one the procedure available in any standard practical chemistry book.

Actually i'm trying to make chromen-4-one from chromone-3-carboxaldehyde but haven't got the product.