1: With BTCEAD; lithium perchlorate in diethyl ether T=0 - 55°C; 2: With acetic acid; zinc in acetone T=20°C; 3 h;

1.1: 71 percent / KOH / dimethylsulfoxide / 0.5 h 2.1: LiClO4; bis(2,2,2-trichloroethyl) azodicarboxylate / diethyl ether / 0 - 55 °C 2.2: 51 percent / Zn; AcOH / acetone / 3 h / 20 °C View Scheme

1.1: 76 percent / I2; aq. HCl / 4.5 h / 140 - 155 °C 2.1: 71 percent / KOH / dimethylsulfoxide / 0.5 h 3.1: LiClO4; bis(2,2,2-trichloroethyl) azodicarboxylate / diethyl ether / 0 - 55 °C 3.2: 51 percent / Zn; AcOH / acetone / 3 h / 20 °C View Scheme