toluene-4-sulfonic acid in benzene 3 h; Heating;

1: 56 percent / 1,3-benzenedicarboxylic acid, ZnCl2 / 4.5 h / 185 °C 2: 99 percent / lithium tri-tert-butoxyaluminum hydride, 2-ethoxyethanol, carbon dioxide / tetrahydrofuran / 1 h / -65 °C 3: 65 percent / p-toluenesulfonic acid / benzene / 3 h / Heating View Scheme

1: 99 percent / lithium tri-tert-butoxyaluminum hydride, 2-ethoxyethanol, carbon dioxide / tetrahydrofuran / 1 h / -65 °C 2: 65 percent / p-toluenesulfonic acid / benzene / 3 h / Heating View Scheme