1.1: titanium(IV) isopropylate / tetrahydrofuran; diethyl ether / Reflux 2.1: 2C20H29O2(1-)*Mn(2+) / benzene / 20 °C 2.2: 2 h / 20 °C 3.1: sulfuric acid / dichloromethane / 2 h / 20 °C View Scheme

lithium aluminium tetrahydride in diethyl ether T=0°C;

1: HAl(Bu-i)2 / CH2Cl2 / 1 h / -78 °C 2: oxalyl chloride; DMSO; Et3N / -78 °C View Scheme