Insights into the diastereoselective control in the sulfa-Michael addition of thiols to nitroalkenes: stereoelectronic effect in the cyclic chelated transition state
two approximately 1,2-diaxial substituents due to stereoelectroniceffectcontrol. The stereoelectroniceffect in the cyclic chelated transition state was probed and verified by tuning the steric bulkiness of the corresponding substituents. The reaction involving 1-nitrocyclohexene provided perfect support for the proposed diastereoselective control model. The current investigation provided not only
thermodynamically-stable isomers is negligible. On the other hand, the palladium-catalyzed sulfonylation of allylic acetates with sodium benzenesulfinate is accompanied by the isomerization to give the thermodynamically-controlled products selectively. These results can be explained by assuming that allylic nitro compounds are more reactive to the palladium catalyst than allylic acetates and sulfones.
erythro-Selective conjugate addition of benzeneselenol to (E)-nitroalkenes and subsequent syn-elimination of benzeneselenenic acid provide a new method for the conversion of (E)-nitroalkenes into (Z)-nitroalkenes.