Michael-initiated ring closure of aryldiazoacetates and α-substituted acroleins under acid catalysis offers a unique opportunity for the stereoselective formation of various tetrasubstituted cyclopropanes.
Water-processable positive-tone photoresists comprising a water-soluble polymer, wherein the polymer contains a heat-labile functional group that renders the polymer insoluble in water or an aqueous base upon heat treatment, and an acid-labile functional group that restores said water or aqueous base solubility to the polymer upon irradiation in the presence of a water-processable photoacid generator, are described. Also described are the methods of making such polymers and photoresists.