1: tetrahydrofuran / 2 h / 0 °C 2: formic acid, Et3N / Pd2(dba)3CHCl3-P(OMe)3 / dioxane / 2 h / Ambient temperature; var. phosphorus ligands; var. times; var. concentrations of formic acid 3: 83 percent / H2 / 5percent Pd/C / methanol / 24 h / Ambient temperature 4: 11 percent / p-TsOH / tetrahydrofuran; H2O / 5 h / 50 °C View Scheme

1: 1) n-BuLi 2: 66 percent / 0.5 h / 150 - 170 °C / reduced pressure View Scheme

Multi-step reaction with 3 steps 1: 42 percent / Br2; aq. AcOH2: 47 percent / benzene3: 83 percent / aq. NaOH