M.C. White/Q. Chen Chem 153 Hydrogenation -154 Week of october 15. 2002 Crystal structure of major diastereomer (CIO) Phenyl (4) CO,M c10 olefin bound to rh via its C6 Phenyl(5) re-face Phenyl(2) major diastereomer formed c 6 in solution(identified by nMr and x-ray crystallography) Phenyl (3 Major enantiomer observed upon Minor enantiomer observed upon Phenyl (1) exposing crystal to H exposing crystal to H] (R)COEt CO2Et NHAc NHAc N-acetyl-(R)-phenylalanine 95%ee HalM.C. White/Q. Chen Chem 153 Hydrogenation -154- Week of October 15, 2002 Rh(I) P O P HN (ClO4-) + CH3 CH3 CO2Me Ph olefin bound to Rh via its re-face major diastereomer formed in solution (identified by NMR and x-ray crystallography) Halpern Science 1982 (217) 401. Crystal structure of major diastereomer CO2Et NHAc N-acetyl-(R)-phenylalanine >95% ee (R) Major enantiomer observed upon exposing crystal to H2: CO2Et NHAc Minor enantiomer observed upon exposing crystal to H2. (S)