hydrogen bromide T=135°C; Hydrolysis; decarboxylation; 12 h;

hydrogen bromide 45 h; Heating;

1: 98 percent / Et3N / CH2Cl2 / 6 h / 20 °C 2: 85 percent / aq. HCO2H; Pd(OAc)2(PPh3)2; Et3N / dimethylformamide / 1 h / 60 °C 3: 96 percent / aq. HBr / 12 h / 135 °C View Scheme

1: 85 percent / Et3N; p-acetamidophenylsulfonyl azide / acetonitrile / 0 - 20 °C 2: 86 percent / Rh(OAc)2 / benzene / 14 h / Heating 3: 98 percent / Et3N / CH2Cl2 / 6 h / 20 °C 4: 85 percent / aq. HCO2H; Pd(OAc)2(PPh3)2; Et3N / dimethylformamide / 1 h / 60 °C 5: 96 percent / aq. HBr / 12 h / 135 °C View Scheme

1: 1.) Li / 1.) Et2O, -10 deg C, 3 h, 2.) Et2O, -10 deg C, 2.6 h 2: 68.4 percent / 10percent Pd-C / cyclohexene / Heating 3: 81 percent / 48percent HBr / 45 h / Heating View Scheme