[Emofreak]

OBVIOUS CONCLUSION:
If you have absorptions at 1670 and 1653 cm-1 and you simultaneously get a -15oC melting point, you have prepared your product but not in a very pure form.

Thanks a lot, that was my guess, my just still curious what could the impurities been and was it due to the presence of sodium hydroxide driving another reaction. so i could learn and not repeat the similar mistake again.

[pgk]

Sorry for the delayed response but I had not seen your second question, all that long.
Anyway, you had probably overheated your product during recrystallization and thus, you had favored oxidation and/or free radical polymerization of your unsaturated product.
Theoretically, NaOH is not involved in such polymerization; except if your ethanol wasn’t fresh and contained acetaldehyde impurities, which were involved in a further cross-aldol condensation/ polymerization, in presence of NaOH.
By the chance, avoid using metallic spatulas during recrystallization, as risking infecting your product with metal cations (Fe, Mo, Ni, etc.) that are Lewis acids and may catalyze similar side reactions. Prefer the glass stirring rods.