Reamination in the recyclization of pyrrolo-[1,2-a]pyrazine salts into 6- and 8-aminoindolizines. General process scheme

Rearrangement of the methyl iodides of 1- and 3-alkyl-substituted pyrrolo1,2-a]pyrazines in the presence of various alkylamines afforded a mixture of 8- and 6-aminoindolizines, respectively, with and without exchange of the methylamine fragment. The ratio of the products of direct and exchange recyclization was dictated by the size of the N-alkyl substituents in the reagent and starting salt. Rearrangement of the 1-alkylpyrrolo1,2-a]pyrazinium salts proceeded via the breaking of the C₍₃₎ -N₍₂₎ bond, and rearrangement of the 3-alkylpyrrolo-1,2-a]pyrazinium salts via the breaking of the C₍₁₎ -N₍₂₎ bond.Translated from Khimiya Geterotsiklicheskikikh Soedinenii, No. 11, pp. 1485–1490, November, 1992.