1: LDA / tetrahydrofuran / 1 h / -78 °C 2: LiAlH4 / diethyl ether / 0.5 h / 20 °C 3: Dess-Martin periodinane / 18 h / 20 °C View Scheme

1: LDA / tetrahydrofuran / 1 h / -78 °C 2: LiAlH4 / diethyl ether / 0.5 h / 20 °C 3: Dess-Martin periodinane / 18 h / 20 °C 4: 25 percent / n-BuLi; HMPA / tetrahydrofuran / 1.5 h / -78 - 0 °C 5: 69 percent / TBAF / tetrahydrofuran / 2.5 h / 20 °C View Scheme