An Improved Synthesis of Optically Pure 4-Boc-5,6-Diphenylmorpholin-2-one and 4-Cbz-5,6-Diphenylmorpholin-2-one

Abstract

A convenient synthesis of optically pure 4-Boc-5,6-diphenylmorpholin-2-one and 4-Cbz-5,6-diphenylmorpholin-2-one by reaction of (+)- or (-)-2-amino-1,2-diphenylethanol with ethyl bromoacetate, followed by N-protection, and p-TsOH-mediated ring-closure is described. The title compounds can be used as synthons for the asymmetric synthesis of N-protected α-amino acids. These lactones are quite stable to storage and handling.

Key words

amino acids - asymmetric synthesis - lactones - 2-amino-1,2-diphenylethanol - ring-closure

References

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