C[N+]1([O-])CC[O:5]CC1.[C:9]1(/[CH:15]=[CH:16]/[C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1.[OH2:23].CC(C)=O.C(#N)C>[O-][Os](=O)(=O)=O.O=[Os](=O)(=O)=O>[C:9]1([C@@H:15]([OH:5])[C@@H:16]([C:17]2[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=2)[OH:23])[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1Resin-OsO4 (0.01 Eq. Wt.), Hydroquinidine 1,4-phthalazinediyl diether (DHQD)2PHAL (0.01 Eq. Wt.) and N-methylmorpholine-N-oxide (1.5 Eq. Wt.) were stirred in the mixed solvent of water/acetone/acetonitrile (in the volume ratio of 1:1:1). To this mixture was added trans-stilbene (1.0 Eq. Wt) and stirred at room temperature for 6 hours. After the reaction, supported osmate catalyst was filtered off and washed with methanol. The combined filtrates were concentrated under reduced pressure. The chiral ligand was recovered from the aqueous layer after acidification (1N HCl). The pure product was obtained by removing the solvent at reduced pressure followed by column chromatography. (R,R)-(+)-1,2-diphenyl-1,2-ethandiol of more than 99.0% of enantiomeric excess was obtained (yield 96%) [∝]D+92.44 (c 1.0, EtOH): e.e.=99.4%
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