Azides obtained from Baylis–Hillman adducts were treated with triphenylphosphine to
give the corresponding iminophosphoranes that underwent aza-Wittig reactions with
aryl isocyanates and then reacted with amines, alcohol, or phenols in the presence
of catalytic amounts of sodium alkoxide or potassium carbonate to give the corresponding
2,3,5-trisubstituted pyrimidin-4(3H)-ones directly in good yields.
Key words
azides - heterocycles - cyclizations - Wittig reactions - amines - alcohols - phenols