In this paper, we report the crossed aldol condensation between the acetone and the 2,5-bis(octyloxy)-terephthalaldehyde (OTP) to obtain new photoluminescent oligomers as potential candidates for the construction of organic luminescent diodes (OLED's). The reaction is carried out in ethanol as solvent, but when THF is added to the reaction medium as co-solvent, a higher molecular weight can be obtained. The analysis of the structure of the product obtained when THF is added was elucidated by H-1 NMR, infrared, ultraviolet-visible (UV-Vis) and fluorescence spectroscopy and the results indicate that the number of repetitive units corresponds with that of a tetramer with an excellent solubility in common organic solvents and intense fluorescence in the green region. Moreover it can be processed by self-assembly in homogeneous thin films with controlled thickness. These results are promising in view of the possible application of this oligomer in electroluminescent diodes.