sodium tetrahydroborate in ethanol T=20°C; 1 h;

1.1: n-BuLi / diethyl ether; hexane / 3 h / 20 °C 1.2: 74 percent / diethyl ether; hexane / 1 h / 20 °C 2.1: 89 percent / sodium borohydride / ethanol / 1 h / 20 °C View Scheme

1.1: 86 percent / sodium hydride / dimethylformamide; various solvent(s) / 3 h / 20 °C 2.1: n-BuLi / diethyl ether; hexane / 3 h / 20 °C 2.2: 74 percent / diethyl ether; hexane / 1 h / 20 °C 3.1: 89 percent / sodium borohydride / ethanol / 1 h / 20 °C View Scheme