Crystal structure of (R)-6-fluoro-2-[(S)-oxiran-2-yl]chroman

Acta Crystallographica Section E: Crystallographic Communications

Clavel, A.¹  Laureano, H.²  Rousselin, Y.³ 

[1] CordenPharma-Synkem, 47 rue de Longvic, 21301 Chenove, France;UMR6302, 9 avenue Alain Savary, 21000 Dijon, France;Universite de Bourgogne, ICMUB–

关键词: CRYSTAL STRUCTURE;    NEBIVOLOL;    ABSOLUTE CONFIGURATION;   

DOI  :  10.1107/S205698901501261X

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

The title compound, C11H11FO2, is a building block in the synthesis of the active pharmaceutical ingredient dl-nebivolol. The synthesis starting from the enanti­omerically pure (R)-6-fluoro-4-oxo-3,4-di­hydro-2H-chromene-2-carb­oxy­lic acid resulted in a mixture of two stereoisomers, namely (R)-6-fluoro-2-[(S)-oxiran-2-yl]chroman and (R)-6-fluoro-2-[(R)-oxiran-2-yl]chroman. The mixture was separated by column chromatography but only one stereoisomer crystallized. The X-ray structure analysis revealed that the solid consisted of the R,S isomer. A similar procedure was repeated for (S)-6-fluoro-4-oxo-3,4-di­hydro-2H-chromene-2-carb­oxy­lic acid and, in this case, the S,R isomer was produced as a crystalline solid. Thus, all four stereoisomers of the title epoxide were obtained and their absolute configuration was assigned. The crystal studied was refined as an inversion twin.

【 授权许可】

CC BY