ChemInform Abstract: Efficient Synthesis of Pyrimido[5,4‐c]pyridazines and of Thiino[2,3‐d]pyrimidines Based on an Aza‐Wittig Reaction/Heterocyclization Strategy.

Abstract

Pyrimidopyridazines (VI) and thiinopyrimidines (XI) are synthesized by a domino aza‐Wittig—heterocyclization reaction of phosphazenes (III) and (X) with phenylisocyanate (IV) and amines (V).