300. Tautomeric azines. Part II. The structure of "malonyl-α- aminopyridine" and its alkylation products: Mesomeric betaines with six-membered rings

Abstract

"Malonyl-α-aminopyridine" exists predominantly as the mesomeric betaine (IV; R=H). Alkylation in alkaline solution with methyl iodide gives the N-methyl derivative (IV; R=Me); alkylation with propargyl bromide gives the O- and the N-propargyl derivative; the single products previously obtained on alkylation and formulated2 as O-derivatives (II; R=OAlk) are mesomeric betaines (IV; R=Alkyl). An unambiguous synthesis of 2-n-propylaminopyridine is described.