1: PPTS; ethanol / 7 h / 55 °C 2: REDAL / toluene; diethyl ether / 3 h / 0 - 20 °C 3: 82 percent / t-butylhydroperoxide; (+)-diethyl tartrate; titanium tetraisopropoxide / CH2Cl2; 2,2,4-trimethyl-pentane / 5 h / -20 °C View Scheme