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DOI: 10.1039/A606295D (Paper) Reference Section for: J. Chem. Soc., Perkin Trans. 1, 1997, 621-624

2,2-Difluoro-1,3,2-oxazaborolidin-5-ones: novel approach for selective side-chain protection of serine and threonine

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Jidong Wang, Yoshio Okada, Wei Li, Toshio Yokoi and Jintao Zhu

Abstract

2,2-Difluoro-1,3,2-oxazaborolidin-5-ones 1, which are synthesized from BF3 and salts of amino acids, are highly effective, convenient and, moreover, inexpensive intermediates for the simultaneous protection of both α-amino and α-carboxy groups in α-amino acids. The new method streamlines the hitherto tedious procedures for side-chain protection of Ser and Thr. Ser(But[hair space]), Thr(But[hair space]), Ser(Bzl) and Thr(Bzl) are obtained by this procedure in high yields and in pure form using highly reactive reagents.

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