C
CHO H
CH 3H
OH
CHH
3C
CH 3 C OHH3 CH OH
(R,R)-2,3-butanediol
syn-hydroxylationCCHO H
CH 3H OHCH 3
C
CO CH 3HHO HCH 3C
CH CH 3H 3 C H
trans-2-Butene (S,S)-2,3-butanediol
at either face ofthealHkene
SynthesisC
CH CH 3H 3
trans-2-ButeneC H- OsO 4
- NaHSO 3 , H 2 O
C
CHO HCH 3H OH
CH 3CCHO H
CH 3H OHCH 3(R,R) (S,S)i) nd produces the desired enantiomeric
2,3-butanediols as a racemic mixture (racemate).2) Synthesis of trans-2-butene:Enantiomeric 2,3-butanediolsThis reaction is stereospecific aRetrosynthetic AnalysisC
CH CH 3 CH 3
anti-add on C
C +^22-Butyneiti HH 3 C H
trans-2-ButeneCH 3Synthesis