Synthesis of alkyl-5H-cyclopenta[b]pyrazines (author's transl)]

Synthesis of alkyl-5H-cyclopenta[b]pyrazines. Alkyl-5H-cyclopenta[b]-pyrazines (sometimes together with 5-alkylidene-5H-6,7-dihydrocyclopenta[b]pyrazines) are prepared by thermal degradation of 5-acetoxy-5H-6,7-dihydrocyclopenta[b]pyrazines; these are obtained by treatment of alkyl-5H-6,7-dihydrocyclopenta[b]pyrazine N-oxides with acetic anhydride. Cyclopenta[b]pyrazines which are potentially present in roasted food flavors possess interesting organoleptic properties.