boron tribromide in dichloromethane T=-30 - 0°C; Product distribution / selectivity;

sodium hydroxide in ethanol Heating;

1.1: 96 percent / DMAP / tetrahydrofuran / Heating 2.1: TMSOTf; TMEDA / diethyl ether / 0.5 h / 0 - 25 °C 2.2: TMEDA; n-BuLi / diethyl ether / 1 h / -78 °C 2.3: 77 percent / I2 / diethyl ether; tetrahydrofuran / 2 h / -78 °C 3.1: aq. NaOH / ethanol / 2 h View Scheme

1.1: s-BuLi; TMEDA / cyclohexane; hexane; tetrahydrofuran / 2 h / -78 °C 1.2: 88 percent / iodine / tetrahydrofuran; hexane; cyclohexane / -78 - 20 °C 2.1: 66 percent / NaOH / ethanol / Heating View Scheme

1.1: TMSOTf; TMEDA / diethyl ether / 0.5 h / 0 - 25 °C 1.2: TMEDA; n-BuLi / diethyl ether / 1 h / -78 °C 1.3: 77 percent / I2 / diethyl ether; tetrahydrofuran / 2 h / -78 °C 2.1: aq. NaOH / ethanol / 2 h View Scheme