1: acetylenecarboxylic acid With 2-bromobenzene boronic acid in dichloromethane T=25°C; 0.166667 h; Inert atmosphere; 2: cyclopenta-1,3-diene in dichloromethane T=25°C; Diels-Alder cycloaddition; 8 h; Inert atmosphere;

water 1.) 4.5 h; Yield given. Multistep reaction;