Baylis–Hillman adducts between pyridine carboxaldehyde derivatives and cyclic enones

Baylis–Hillman (BH) adducts were synthesized using pyridinecarboxaldehyde derivatives and cyclic enones. The Baylis–Hillman reaction was examined by employing various organic tertiary bases and solvents. It was observed that DBU in MeOH as well as imidazole and N-methylimidazole in aqueous MeOH are very effective. These pyridinecarboxaldehydes were reactive and efficient towards the Baylis–Hillman reaction and the resulting adducts are highly stable. The crystal structure for one of the BH adducts was determined.