titanium(IV) isopropylate; tert.-butylhydroperoxide; diethyl (2R,3R)-tartrate in dichloromethane T=-20°C;

sodium ethanolate in ethanol 1.) 0 deg C, 20 min, 2.) 25 deg C, 12 h;

titanium(IV) isopropylate; tert.-butylhydroperoxide; diethyl (2R,3R)-tartrate in dichloromethane 4 Angstroem molecular sieves; 1.)-20 deg C, 0.5 h, 2.) -10 deg C, 29 h; Yield given. Yields of byproduct given. Title compound not separated from byproducts;

1: (S)-α,α-bis(4-hexylphenylthio)-2-pyrrolidinemethanol trimethylsilylether; dihydrogen peroxide / ethanol; water / 16 h / 20 °C / |Green chemistry 2: sodium tetrahydroborate / methanol / 0.33 h / 0 °C View Scheme