1: With IndRu(PPh3)2Cl; camphor-10-sulfonic acid in tetrahydrofuran T=20°C; 0.0833333 h; Inert atmosphere; 2: With indium trifluoromethanesulfonate in tetrahydrofuran 1 h; RefluxInert atmosphere;

in sulfuric acid T=100°C; 12 h;

potassium carbonate in N,N-dimethyl-formamide 24 h; Ambient temperature;

1.1: 66 percent / HCl / acetic acid; H2O / 4 h / 100 °C 2.1: oxalyl chloride; DMF / CH2Cl2 / 4 h / 20 °C 2.2: 78 percent / NaH / tetrahydrofuran / 4 h / 70 °C 3.1: 79 percent / aq. H2SO4 / 12 h / 100 °C View Scheme

1.1: oxalyl chloride; DMF / CH2Cl2 / 4 h / 20 °C 1.2: 78 percent / NaH / tetrahydrofuran / 4 h / 70 °C 2.1: 79 percent / aq. H2SO4 / 12 h / 100 °C View Scheme

1.1: 90 percent / dimethylsulfoxide / 72 h / 20 °C 2.1: 66 percent / HCl / acetic acid; H2O / 4 h / 100 °C 3.1: oxalyl chloride; DMF / CH2Cl2 / 4 h / 20 °C 3.2: 78 percent / NaH / tetrahydrofuran / 4 h / 70 °C 4.1: 79 percent / aq. H2SO4 / 12 h / 100 °C View Scheme

1.1: 89 percent / pyridine / 12 h / 20 °C 2.1: 90 percent / dimethylsulfoxide / 72 h / 20 °C 3.1: 66 percent / HCl / acetic acid; H2O / 4 h / 100 °C 4.1: oxalyl chloride; DMF / CH2Cl2 / 4 h / 20 °C 4.2: 78 percent / NaH / tetrahydrofuran / 4 h / 70 °C 5.1: 79 percent / aq. H2SO4 / 12 h / 100 °C View Scheme

1.1: 89 percent / pyridine / 12 h / 20 °C 2.1: 90 percent / dimethylsulfoxide / 72 h / 20 °C 3.1: 66 percent / HCl / acetic acid; H2O / 4 h / 100 °C 4.1: oxalyl chloride; DMF / CH2Cl2 / 4 h / 20 °C 4.2: 78 percent / NaH / tetrahydrofuran / 4 h / 70 °C 5.1: 79 percent / aq. H2SO4 / 12 h / 100 °C View Scheme

1.1: 61 percent / Zn(BH4)2 / tetrahydrofuran / 10 h / Heating 2.1: 89 percent / pyridine / 12 h / 20 °C 3.1: 90 percent / dimethylsulfoxide / 72 h / 20 °C 4.1: 66 percent / HCl / acetic acid; H2O / 4 h / 100 °C 5.1: oxalyl chloride; DMF / CH2Cl2 / 4 h / 20 °C 5.2: 78 percent / NaH / tetrahydrofuran / 4 h / 70 °C 6.1: 79 percent / aq. H2SO4 / 12 h / 100 °C View Scheme

1: 99 percent / NaI / acetone / 24 h / Heating 2: 91 percent / K2CO3 / dimethylformamide / 24 h / Ambient temperature View Scheme