Highly diastereoselective heterogeneously catalyzed hydrogenation of enamines for the synthesis of chiral beta-amino acid derivatives.
Pure (Z)-enamines readily prepared from beta-ketoesters and amides using (S)-phenylglycine amide were hydrogenated with very high diastereoselectivities (up to 200:1) using heterogeneous catalysis. Hydrogenolytic cleavage of the (S)-phenylglycine amide afforded the corresponding chiral beta-aminoesters and amides. The high geometrical purity of the (Z)-enamine and a simple activation procedure for the PtO2 catalyst are essential in achieving high selectivity.
Ikemoto
Norihiro
N
Department of Process Research and the Catalysis and Reaction Discovery and Development Lab, Merck and Co., Inc., P.O. Box 2000, Rahway, New Jersey 07065-0900, USA. norihiro_ikemoto@merck.com
Tellers
David M
DM
Dreher
Spencer D
SD
Liu
Jinchu
J
Huang
Angie
A
Rivera
Nelo R
NR
Njolito
Eugenia
E
Hsiao
Yi
Y
McWilliams
J Christopher
JC
Williams
J Michael
JM
Armstrong
Joseph D
JD
Sun
Yongkui
Y
Mathre
David J
DJ
Grabowski
Edward J J
EJ
Tillyer
Richard D
RD
D000577:Amides / Q000138:chemical synthesis / Q000737:chemistry; D000588:Amines / Q000737:chemistry*; D000596:Amino Acids / Q000138:chemical synthesis / Q000737:chemistry*; D002384:Catalysis; D018360:Crystallography, X-Ray; D003903:Deuterium; D004952:Esters / Q000138:chemical synthesis / Q000737:chemistry; D006865:Hydrogenation; D013237:Stereoisomerism
D000577:Amides; D000588:Amines; D000596:Amino Acids; D004952:Esters; D003903:Deuterium