A REINVESTIGATION OF THE ALPHA-ALKYLATION OF 4-MONOSUBSTITUTED 2-PHENYLOXAZOL-5(4H)-ONES (AZLACTONES) - A GENERAL ENTRY INTO HIGHLY FUNCTIONALIZED ALPHA,ALPHA-DISUBSTITUTED ALPHA-AMINO-ACIDS

被引：24

作者：

OBRECHT, D

BOHDAL, U

RUFFIEUX, R

MULLER, K

机构：

[1] Pharma Research New Technologies (PRT), F Hoffmann- la Roche AG, Basel

来源：

HELVETICA CHIMICA ACTA | 1994年 / 77卷 / 05期

关键词：

D O I：

10.1002/hlca.19940770520

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Novel, more reliable and general reaction conditions for the alpha-alkylation of 4-monosubstituted 2-phenyloxazol-5(4H)-ones (= 4-monosubstituted 2-phenyl-azlactones) rac-2 to 4,4-disubstituted 2-phenyloxazol-5(4H)-ones rac-1 were found (Scheme 2). Thus, a whole range of highly functionalized rac-1 were prepared in medium-to-good overall yields (40-90%, see Table). Azlactones rac-1 are ideal precursors for the synthesis of optically pure alpha,alpha-disubstituted (R)- and (S)-alpha-amino acids.

引用

页码：1423 / 1429

页数：7

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