1-(2,4,6-Triisopropylphenyl)ethylamine: A New Chiral Auxiliary for the Asymmetric Synthesis of γ-Amino Acid Derivatives

The title compound has proven to be an excellent chiral auxiliary for nitrones in SmI2-mediated reductive coupling with α,β-unsaturated esters. A variety of such nitrones, prepared from aldehydes and enantiopure N-hydroxy-1-(2,4,6-triisopropylphenyl)ethylamine, afforded γ-N-hydroxyamino esters in high yields and diastereomeric purity. These adducts, readily available as either enantiomer, could be transformed into γ-N-acetoxyamino esters, N-Boc-γ-amino esters, and γ-lactams.