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.
Lecachey
Baptiste
B
IRCOF, CNRS UMR 6014 & FR 3038, Université de Rouen, 76821 Mont St. Aignan Cedex, France.
Duguet
Nicolas
N
Oulyadi
Hassan
H
Fressigné
Catherine
C
Harrison-Marchand
Anne
A
Yamamoto
Yasutomo
Y
Tomioka
Kiyoshi
K
Maddaluno
Jacques
J
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