p‐substituted phenyl 2‐nitrovinyl sulfones was studied through different spectral methods. It has been found that the nucleophilic substitution reactions of sodium phenylsulfinates with 1‐chloro‐2‐nitroethene occur stereospecifically. The formation of E‐isomers of this type of substituted phenyl vinyl sulfones was confirmed by FTIR and NMR spectroscopy. It was suggested that the E‐isomers formation was determined