Preparation by yeast reduction and determination of the sense of chirality of enantiomerically pure ethyl (−)-4,4,4-trichloro-3-hydroxy- and (+)-4,4,4-trifluoro-3-hydroxybutanoate
作者:Dieter Seebach、Philippe Renaud、W. Bernd Schweizer、Max F. Züger、Marie-Josèphe Brienne
DOI:10.1002/hlca.19840670721
日期:1984.11.7
and 4,4,4-trifluoro-3-oxobutanoate by fermenting baker's yeast (Saccharomyces cerevisiae) on a preparative scale (20–50 g in ca. 3 1 of H2O) gave 70–80% yields of the trichloro- [(−)-(S)-1a] and trifluoro-hydroxyesters [(+)-(R)2a] of ca. 85 and 45% ee, respectively. Both, (−)-1a and (+)-2a could be obtained in > 98% ee by subsequent crystallization (of(−)-1, (+)-2a or the 3,5-dinitrobenzoate (+)-2b. The
通过以制备规模发酵面包酵母(酿酒酵母)(在H 2 O的3 1中约20–50 g)来还原4,4,4-三氯乙基和4,4,4-三氟-3-氧代丁酸乙酯得到三氯70-80%的产率[( - ) - (小号) - 1A ]和三氟-羟基酯- [(+)(- [R )2A的] CA。ee分别为85和45%。(-)- 1a和(+)- 2a均可通过随后的结晶((-)- 1,(+)- 2a或3,5-二硝基苯甲酸酯(+)- 2b)在大于98%ee的条件下获得。确定了两种羟基酯的绝对构型(a)通过CF 3-衍生物(+)- 2a及其CH的二硝基苯甲酸酯的熔融图和混合熔点(图1的差示扫描量热法,图1)通过化学相关((-)- 1a),(b)3 -analogue 8,和C ^)通过酯的X射线分析2F由(+) -图2a和( - ) -樟脑酰氯衍生化(图2和3)。