Condensation of Amines with S -Methyl Thiouronium Salts: Another Entry for the Synthesis of Amidines.

We present a condensation of primary aryl or alkyl amines with S -methyl thiouronium salts to obtain N , N , N ′-trisubstituted amidines. High yields, short reaction times, and a fair substrate scope are the noteworthy features of this protocol. Surprisingly, the reaction of a thiouronium salt with 4-aminopyridine gave 1-(4-methoxybenzoyl)piperidine. [ABSTRACT FROM AUTHOR]