Hydroxy derivatives of benzalthiophenone

It is the purpose of this work to prepare a series of these chalcones containing the thiophene ring. The compounds were prepared by the condensation of a series of benzaldehydes with acetylthiophene dissolved in dry ethylacetate and saturated with dry HCl. The benzaldehyde compounds were benzaldehyde, m-hydroxybenzaldehyde, o-hydroxybenzaldehyde, O-p-dihydroxybenzaldehyde and vanillin. To prevent the oxidation of the hydroxy groups of the benzaldehydes, the compounds were benzolated with benzoylchloride. The condensed products were debenzoylated with NaOH solution in an atmosphere of nitrogen to prevent oxidation during the debenzoylation process