potassium carbonate in tetrahydrofuran; methanol T=20°C; 4 h;

1: 80 percent / KOH / ethanol / Heating 2: 83 percent / I2; Hg(OAc)2 / CH2Cl2 / 20 °C 3: 89 percent / CuI; TEA / [PdCl2(PPh3)2] / tetrahydrofuran / 20 °C 4: 95 percent / K2CO3 / tetrahydrofuran; methanol / 4 h / 20 °C View Scheme

1: 89 percent / CuI; TEA / [PdCl2(PPh3)2] / tetrahydrofuran / 20 °C 2: 95 percent / K2CO3 / tetrahydrofuran; methanol / 4 h / 20 °C View Scheme

1: 80 percent / KOH / ethanol / Heating 2: 83 percent / I2; Hg(OAc)2 / CH2Cl2 / 20 °C 3: 89 percent / CuI; TEA / [PdCl2(PPh3)2] / tetrahydrofuran / 20 °C 4: 95 percent / K2CO3 / tetrahydrofuran; methanol / 4 h / 20 °C View Scheme

1: 69 percent / K2CO3 / acetone / 3 h / Heating 2: 41 percent / KIO3; I2; acetic acid / H2SO4 / H2O / 11 h / Heating 3: 65 percent / CuI; Et3N / Pd(PPh3)2Cl2 / tetrahydrofuran / 24 h / 20 °C 4: 86 percent / KOH / tetrahydrofuran; methanol / 3 h View Scheme