One‐Pot Three‐Component Synthesis of 4‐Arylpyrimidin‐2‐amines Using Solid Calcium Carbide as a Surrogate of Gaseous Acetylene.

An efficient method for the synthesis of 4‐arylpyrimidin‐2‐amines by the reactions of various aromatic aldehydes, guanidine and calcium carbide through one‐pot three‐component procedure is described. The salient features for this protocol are the use of an inexpensive and easy‐to‐handle solid calcium carbide instead of flammable and explosive gaseous acetylene as an alkyne source, cheap transition‐metal mediator, commercially available starting materials, wide substrate scope, satisfactory yield, and the simple workup procedure. The related reaction can also be extended to gram scale. [ABSTRACT FROM AUTHOR]