Diastereoselective Hydroxylation of N-tert-Butanesulfinyl Imines with 2-(Phenylsulfonyl)-3-phenyloxaziridine (Davis Oxaziridine)

The diastereoselective alpha-hydroxylation of N-tertbutanesulfinyl metallodienenamine and metalloenamines with Davis oxaziridine affords alpha-hydroxy N-sulfinyl imines with 50- 88% yield and up to 98:2 diastereomeric ratio. Dramatic changes in diastereoselectivity and stereoselectivity were observed by choice of metal bases. The mechanistic understanding for the switch in diastereoselectivity was assisted by DFT computational modeling, which suggests the facial approach is governed by aza-enolate geometry. A one-pot protocol for the asymmetric synthesis of 1,2-amino alcohols is described.

Automated summary

The diastereoselective alpha-hydroxylation of N-tertbutanesulfinyl metallodienenamine and metalloenamines with Davis oxaziridine has been achieved with high yields and diastereomeric ratios. The choice of metal bases dramatically influences the diastereoselectivity and stereoselectivity of the reaction. DFT computational modeling has provided mechanistic insights, suggesting the importance of aza-enolate geometry in the facial approach. A one-pot protocol for the asymmetric synthesis of 1,2-amino alcohols has been developed.