Enantioselective conjugate addition of a lithium ester enolate catalyzed by chiral lithium amides: a possible intermediate characterized.
Two 1:1 noncovalent mixed aggregates between a lithium enolate and two diastereomeric lithium amides have been identified spectroscopically in THF. The NMR data, as well as DFT theoretical calculations, shine some light on a puzzling reversal of induction, observed when switching from one diastereomer of the amide to the other in the enantioselective Michael addition of the lithium enolate to an unsaturated ester.
IRCOF, CNRS UMR 6014 & FR 3038, Université de Rouen, 76821 Mont St. Aignan Cedex, France.
Baptiste
B
Lecachey
Nicolas
N
Duguet
Hassan
H
Oulyadi
Catherine
C
Fressigné
Anne
A
Harrison-Marchand
Yasutomo
Y
Yamamoto
Kiyoshi
K
Tomioka
Jacques
J
Maddaluno
D000577:Amides / Q000737:chemistry*; D002384:Catalysis; D008094:Lithium / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D013237:Stereoisomerism
D000577:Amides; D009942:Organometallic Compounds; D008094:Lithium