NEW INSIGHTS ON THE REACTION OF BENZOFURANES WITH AROMATIC-ALDEHYDES - SYNTHESIS OF NEW TRIPHENYLMETHANE-TYPE DYES

New molecules with a triphenylmethane-type structure have been synthes ised based on the structure of coloured compounds obtained from natura l substrates. Satisfactory yields were obtained from benzofuran deriva tives as starting material, which have been condensed in methanol with aromatic aldehydes in the presence of catalytic amounts of mineral ac ids. Several of the new compounds behave as pH indicators. The condens ation products, obtained from suitably functionalized starting product s, can be easily oxidised giving rise to new triphenylmethane-type dye s, such as 10.