Very high 1,2- and 1,3-asymmetric induction in the reactions of allylic boron compounds with chiral imines

1986 ◽  
Vol 108 (24) ◽  
pp. 7778-7786 ◽  
Author(s):  
Yoshinori. Yamamoto ◽  
Kazuhiro. Maruyama ◽  
Toshiaki. Komatsu ◽  
Wataru. Ito
Keyword(s):  
Asymmetric Induction ◽  
Boron Compounds ◽  
Chiral Imines ◽  
Very High

ChemInform Abstract: Very High 1,2- and 1,3-Asymmetric Induction in the Reactions of Allylic Boron Compounds with Chiral Imines.

ChemInform ◽  
1987 ◽  
Vol 18 (16) ◽  
Author(s):  
Y. YAMAMOTO ◽  
S. NISHII ◽  
K. MARUYAMA ◽  
T. KOMATSU ◽  
W. ITO
Keyword(s):  
Asymmetric Induction ◽  
Boron Compounds ◽  
Chiral Imines ◽  
Very High

scholarly journals Enantiodivergent Aldol Condensation in the Presence of Aziridine/Acid/Water Systems

Symmetry ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 930 ◽  
Author(s):  
Adam Marek Pieczonka ◽  
Lena Marciniak ◽  
Michał Rachwalski ◽  
Stanisław Leśniak
Keyword(s):  
Aldol Condensation ◽  
Aldol Reaction ◽  
Aromatic Aldehydes ◽  
Water Systems ◽  
Acid Water ◽  
Asymmetric Aldol ◽  
Asymmetric Aldol Reaction ◽  
Chiral Imines ◽  
Very High

A series of novel chiral imines was synthesized from corresponding aldehydes and 1-(2-aminoalkyl)aziridines with good chemical yields. Such imines were tested as catalysts in the direct asymmetric aldol reaction between aromatic aldehydes and acetone/cyclohexanone in the presence of catalytic amounts of water and an acidic additive. The corresponding aldol products were formed in excellent yields and with very high enantioselectivities (98% and 99% ee, respectively).

Optisch aktive Übergangsmetall-Komplexe, LXIII [1] Asymmetrische Induktion in C5H5Mo(CO)2LX-Diastereomeren-Gleichgewichten / Optically Active Transition Metal Complexes, LXIII [1] Asymmetrie Induction in C5H5Mo(CO)2LX Diastereoisomer Equilibria

1979 ◽  
Vol 34 (10) ◽  
pp. 1418-1423 ◽  
Author(s):  
Henri Brunner ◽  
Isabella Bauer ◽  
Rainer Lukas
Keyword(s):  
Transition Metal Complexes ◽  
Nmr Spectra ◽  
Optically Active ◽  
Asymmetric Induction ◽  
Chiral Ligand ◽  
Phenyl Substituent ◽  
H Nmr ◽  
Weak Attraction ◽  
Active Transition ◽  
Very High

Abstract The thioamidato complexes C5H5(CO)2MoSC(R)NCH(CH3) (Ar), derived from acetic acid R = CH3 and benzoic acid R = C6H5, were prepared and characterized. The diastereo-isomers, differing in their 1H NMR spectra, were partly separated by fractional crystallization. After equilibration with respect to the labile Mo configuration the diastereoisomer ratio, a measure for the asymmetric induction from the chiral ligand on the formation of the two Mo configurations at equilibrium, was determined by 1H NMR integration. The asymmetric induction is very high for Ar = o-tolyl [76% (R = C6H3) and 84% (R = C6H5)] compared to Ar = phenyl [48% (R = CH3) and 56% (R = C6H5)] and Ar = m-and p-tolyl [52 and 44% (R = CH3)]. The (CO)3Cr complexed phenyl substituent with only 10% asymmetric induction does not show the β-phenyl effect, a weak attraction between aryl groups in β-position to the metal atom and the MC5H5 moiety.

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