1: With mercury(II) diacetate in tetrahydrofuran; water T=25°C; 1 h; 2: With sodium hydroxide; sodium tetrahydroborate T=0°C; Further stages.;

1: 84 percent / NaBH4 / methanol 2: 1) HgOAc, NaOAc, 2) KI, 3) I2 / 1) H2O, RT, 15 min, 3) CCl4, 28 h 3: 50 percent / LiAlH4 / diethyl ether View Scheme