Influence of an ortho-sulfinyl group on the configurational stability of α-lithiated aryloxiranes: deuteration of tolylsulfinyl styrene oxides

The influence of the p-tolylsulfinyl group, located at ortho-, meta-, and para-position, on the regio- and stereoselectivity of the deuteration reactions of substituted styrene oxides has been investigated. The sulfinyl group at an ortho-position reduces the configurational stability of α-lithiated styrene oxides, whereas meta- and para-sulfinyl derivatives completely control the regioselectivity only yielding deuterated products at the aromatic ring due to its strong ortho-director effect.