1: triethylamine / tetrahydrofuran; CCl4 / 2 h / Ambient temperature 2: 25 percent / sodium metal / liquid ammonia View Scheme

Multi-step reaction with 2 steps 1: 72 percent / H2 / 5 percent palladised charcoal / methanol / 20 h2: 86 percent / boron tribromide / CH2Cl2 / 2 h / Ambient temperature  

Multi-step reaction with 3 steps 1: 52 percent / lithium aluminium hydride / tetrahydrofuran2: 72 percent / H2 / 5 percent palladised charcoal / methanol / 20 h3: 86 percent / boron tribromide / CH2Cl2 / 2 h / Ambient temperature