Evans Asymmetric Aldol Addition

Schematic representation of the Evans Asymmetric Aldol Addition.
Mechanism of the Evans Asymmetric Aldol Addition
Mechanism of the Evans Asymmetric Aldol Addition
Sample reactions
intermediate structure intermediate structure
n-Bu2BOTf, Et3N
CH2Cl2
-78 to -40 °C, 2.5 h, 96%
intermediate structure
intermediate structure
n-Bu2BOTf, i-Pr2NEt, Acrolein
CH2Cl2
-78 to 0 °C, 90 min, 93%
intermediate structure
intermediate structure intermediate structure
n-Bu2BOTf, Et3N
CH2Cl2
-78 to 0 °C, 80 min, 86%
intermediate structure
intermediate structure intermediate structure
n-Bu2BOTf, Et3N
CH2Cl2
-78 to 0 °C, 3.5 h, 93%
intermediate structure