Synthesis of 5-Arylthio-3-hydroxyphthalates by the First [4+2] Cycloadditions of 3-Arylthio-1-silyloxy-1,3-butadienes with Dimethyl Acetylenedicarboxylate - Iqbal, Inam; Imran, Muhammad; Langer, Peter (Synthesis, 2009)