Ruddock P L, Williams D J, Reese P B
Chemistry Department, University of the West Indies, Mona, Kingston, Jamaica.
Steroids. 1998 Dec;63(12):650-64. doi: 10.1016/s0039-128x(98)00076-2.
The effect of the C-3 substituent on the reaction of androst-5-enes with mercury(II) trifluoroacetate in dichloromethane (modified Treibs oxidation) was investigated. 3 beta-Acyloxyandrost-5-en-17-ones gave 3 beta-acyloxy-6 beta-hydroxyandrost-4-en-17-ones accompanied by 3 beta-acyloxy-6-chloromercuriandrost-5-en-17-ones. 3 beta-Acetoxy-6 beta-trifluoroacetoxyandrost-4-en-17-one and 3 beta-acetoxy-4 beta-trifluoroacetoxyandrost-5-en-17-one were revealed to be intermediates in the reaction. The formation of the chloromercury steroids indicated participation in the reaction by the solvent. With 3 alpha-acetoxyandrost-5-en-17-one as substrate, a complete reversal in the product distribution was observed. 3 beta-Haloandrost-5-en-17-ones gave mainly products that reflected SN1 substitution of the halide. 3 beta-Hydroxy- and 3 beta-trifluoroacetoxyandrost-5-en-17-ones were formed. 3 beta-Methoxyandrost-5-en-17-one afforded in nearly identical yields androst-4-ene-3,17-dione, 3 beta-methoxy-6 beta-hydroxyandrost-4-en-17-one, 3 beta-methoxy-6-chloromercuriandrost-5-en-17-one and 6 beta-hydroxyandrost-4-ene-3,17-dione while androst-5-en-17-one yielded 3 beta,6 beta-dihydroxyandrost-4-en-17-one, androst-5-ene-7,17-dione and androst-4-ene-3,17-dione. The effects of solvent and other mercury salts on the reaction were also studied. Treibs oxidation was successful in chloroform, carbon tetrachloride, and dibromomethane, but not in other solvents tested. 3 beta-Acetoxy-6-bromomercuriandrost-5-en-17-one was obtained in dibromomethane. Replacement of the reagent by mercury(II) trichloroacetate altered the intermediates formed but not the products. Mercury(II) tribromoacetate was unreactive, however.
研究了C-3取代基对5-雄烯与三氟乙酸汞（II）在二氯甲烷中反应（改良的特赖布斯氧化反应）的影响。3β-酰氧基-5-雄烯-17-酮生成3β-酰氧基-6β-羟基-4-雄烯-17-酮，同时伴有3β-酰氧基-6-氯汞基-5-雄烯-17-酮。已证实3β-乙酰氧基-6β-三氟乙酰氧基-4-雄烯-17-酮和3β-乙酰氧基-4β-三氟乙酰氧基-5-雄烯-17-酮是该反应的中间体。氯汞甾体的形成表明溶剂参与了反应。以3α-乙酰氧基-5-雄烯-17-酮为底物时，观察到产物分布完全反转。3β-卤代-5-雄烯-17-酮主要生成反映卤化物SN1取代的产物。生成了3β-羟基-和3β-三氟乙酰氧基-5-雄烯-17-酮。3β-甲氧基-5-雄烯-17-酮生成的雄甾-4-烯-3,17-二酮、3β-甲氧基-6β-羟基-4-雄烯-17-酮、3β-甲氧基-6-氯汞基-5-雄烯-17-酮和6β-羟基-雄甾-4-烯-3,17-二酮的产率几乎相同，而5-雄烯-17-酮生成3β,6β-二羟基-4-雄烯-17-酮、5-雄烯-7,17-二酮和雄甾-4-烯-3,17-二酮。还研究了溶剂和其他汞盐对该反应的影响。特赖布斯氧化反应在氯仿、四氯化碳和二溴甲烷中成功进行，但在其他测试溶剂中未成功。在二溴甲烷中得到了3β-乙酰氧基-6-溴汞基-5-雄烯-17-酮。用三氯乙酸汞（II）替代试剂改变了形成的中间体，但未改变产物。然而，三溴乙酸汞（II）没有反应活性。
