1: 52 percent / BH3*THF / tetrahydrofuran / 16 h / Ambient temperature; other solvent, reagent, temperature, reaction time 2: 54 percent / LDA / tetrahydrofuran / -50 - 0 °C / other reagent, temperature, reaction time 3: O2, salcomine / dimethylformamide / 2 h / Ambient temperature 4: methanol / 23 h / Ambient temperature View Scheme

1: 52 percent / BH3*THF / tetrahydrofuran / 16 h / Ambient temperature; other solvent, reagent, temperature, reaction time 2: 54 percent / LDA / tetrahydrofuran / -50 - 0 °C / other reagent, temperature, reaction time 3: O2, salcomine / dimethylformamide / 2 h / Ambient temperature 4: NH4Cl / methanol / 13 h / Ambient temperature View Scheme