diastereoselective

Adjective

 * Of, pertaining to, or exhibiting diastereoselectivity
 * Aldrichimica Acta Volume 30 No 4 (pdf) from Sigma-Aldrich
 * This electronwithdrawing functionality not only inhibits the tendency of vinyldiazomethanes to rearrange to 3H-pyrazoles, but is also necessary to achieve highly diastereoselective cyclopropanations.