Enantiopure arenesulfenic acids as intermediates in stereoselective synthesis

New transient arenesulfenic acids were involved in the synthesis of enantiopure 2-arylsulfinyl-1,3-dienes, showing central or axial chirality of the substituted arene residue, apart from the chirality related to the stereogenic sulfur atom. Some of the obtained dienes, that is, (Sa,SS)- and (SaRS)-2-(20-hydroxy-1,10-binaphthalen-2-sulfinyl)-3-methyl-1,3-butadienes, were subjected to diastereoselective Diels– Alder cycloadditions with N-methylmaleimide. Removal of the arylsulfoxide auxiliary, in the major adduct, was accomplished by reductive cleavage with Raney nickel.