Inter- and Intramolecular Cycloadditions of Nitroalkenes with Olefins. 2-Nitrostyrenes

Article abstract of DOI:10.1021/jo00044a029

Aromatic nitroalkenes 9 - 12 underwent Lewis acid catalyzed cycloadditions with various cyclic alkenes to afford high yields of nitronates 25 - 30 with exclusive anti selectivity.Hammett studies helped to further delineate the role of the Lewis acid.Reaction of nitroalkenes 8 and 10 with various cyclic dienes in the presence of a Lewis acid demonstrated the ability of nitroalkenes to behave as dienes in cycloadditions.The major products were the syn diastereomers which arise from an endo-folded transition structure.Finally, intramolecular cycloaddition of 36 - 39 allowed a correlation between the stereochemical course of the reaction and positions of sp² centers in the tether to be addressed.