Toshinari H. Kurniadi, R. B. Rhlid, M. Juillerat
Aug 4, 2003
Citations
0
Influential Citations
6
Citations
Journal
Tetrahedron
Abstract
Abstract The aroma compounds 2-ethenyl-3,5-dimethylpyrazine 1 and 3-ethenyl-2,5-dimethylpyrazine 2 were synthesized via a new chemical route. The key steps of the synthesis involve cyclocondenzation of 1-[bicyclo[2.2.1]5-hepten-2-yl]-1,2-propanedione and 1,2-propanediamine, aromatization of the resulting 5,6-dihydropyrazines, and subsequent Retro-Diels–Alder reaction to generate pyrazines 1 and 2 . Pyrazine 1 , a powerful odorant, was obtained in large excess (8:2) when endo -1-[bicyclo[2.2.1]5-hepten-2-yl]-1,2-propanedione was used as intermediate substrate.