1: (R,R)-1,2-dicyclohexylethanediol (R)-[1-(benzyloxy)ethyl]boronate With sodium hydroxide; 2,2-bis(hydroxymethyl)-1,3-propanediol; TAPS in diethyl ether; water T=20°C; Hydrolysis; transesterification; 18 h; 2: With hydrogenchloride; water T=0°C; Hydrolysis; pH=3; 3: (S,S)-(-)-1,2-dicyclohexyl-ethane-1,2-diol in hexane Esterification; 18 h;