Cycloadditions of 2-nitro 1,3-dienes to enamines. Asymmetric induction and synthesis of unsaturated nitroketones and Diels-Alder adducts via [4+2] heterocycloadditions

Article abstract of DOI:10.1016/S0040-4039(00)61168-1

2-Nitro 1,3-dienes, generated in situ from the corresponding nitroseleno compounds, react with enamines affording [4+2] heterocycloadducts of different stability. With chiral enamines a high asymmetric induction was observed in some cases. Some of the adducts were readily hydrolyzed to unsaturated γ-nitroketones whereas others spontaneously rearranged to Diels-Alder-type carbocycloadducts.