α-Hydroxylation of α,α-Disubstituted N-tert-Butanesulfinyl Ketimines with Molecular Oxygen: Stereoselective Synthesis of α-Tertiary Hydroxyimines

alpha-Tertiary hydroxyimines were stereoselectively synthesized from enantioenriched N-tert-butanesulfinyl ketimines using potassium tertbutoxide, molecular oxygen, and trimethyl phosphite. The stereoselective hydroxylation of acyclic ketimines bearing two sterically similar alpha-substituents was achieved by controlling the geometry of the metalloenamine intermediates and the facial selectivity of hydroxylation. The synthetic utility of the resulting alpha-tertiary hydroxyimines was demonstrated through the successful diastereoselective synthesis of highly substituted beta-amino alcohols.

Automated summary

In this study, alpha-tertiary hydroxyimines were stereoselectively synthesized from enantioenriched N-tert-butanesulfinyl ketimines using potassium tertbutoxide, molecular oxygen, and trimethyl phosphite. The stereoselective hydroxylation of acyclic ketimines with two sterically similar alpha-substituents was achieved by controlling the geometry of the metalloenamine intermediates and the facial selectivity of hydroxylation, demonstrating the synthetic utility through successful diastereoselective synthesis of highly substituted beta-amino alcohols.