1: 98 percent / DIBAL / tetrahydrofuran / -78 °C / variation of addition method and reagents 2: 80 percent / LiAlH4 / 6 h / Ambient temperature 3: 1.) trimethyloxonium fluoroborate, 2.) HONa solution / 1.) THF, room temperature, 2.) 1 h View Scheme

1: 98 percent / DIBAL / tetrahydrofuran / -78 °C / variation of addition method and reagents 2: 80 percent / LiAlH4 / 6 h / Ambient temperature 3: 1.) trimethyloxonium fluoroborate, 2.) HONa solution / 1.) THF, room temperature, 2.) 1 h View Scheme