Abstract

A selective debromination of tetracyclic dibrominated bis-γ-lactones in the presence of triethylamine and mesyl chloride is reported. Both mesyl chloride and triethylamine are essential for the debromination process. The reduction is proposed to proceed through halophilic substitution of electrophilic bromine. The source of the halophile in this reaction is believed to be triethyl(mesyl)ammonium chloride. The nonoccurrence of debromination in dibromo bis-γ-lactones with tosyl chloride and triethylamine as reagents suggests that the formation of a source of well-dissociated chloride ions during the reaction is necessary. Furthermore, selective debromination of dibrominated bis-γ-lactones was also achieved by using pyridine–thionyl chloride as a reagent. Alternatively, potassium chloride–[18-crown-6] was demonstrated to be a suitable source of chloride ion for the reduction of bromolactones.

A selective debromination of tetracyclic dibrominated bis-γ-lactones in the presence of triethylamine and mesyl chloride is reported. Both mesyl chloride and triethylamine are essential for the debromination process. The reduction is proposed to proceed through halophilic substitution of electrophilic bromine. The source of the halophile in this reaction is believed to be triethyl(mesyl)ammonium chloride. The nonoccurrence of debromination in dibromo bis-γ-lactones with tosyl chloride and triethylamine as reagents suggests that the formation of a source of well-dissociated chloride ions during the reaction is necessary. Furthermore, selective debromination of dibrominated bis-γ-lactones was also achieved by using pyridine–thionyl chloride as a reagent. Alternatively, potassium chloride–[18-crown-6] was demonstrated to be a suitable source of chloride ion for the reduction of bromolactones.

中文翻译：

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三乙胺-甲基氯/亚硫酰氯：一种基于二喹烷的α-溴-γ-内酯加氢脱溴的试剂

摘要

据报道在三乙胺和甲磺酰氯存在下四环二溴代双-γ-内酯的选择性脱溴。甲磺酰氯和三乙胺对于脱溴过程都是必不可少的。建议通过亲电子溴的卤代取代进行还原。据认为，该反应中的嗜盐菌的来源是氯化三乙基（甲磺酰基）铵。在二溴双-γ-内酯中不存在以甲苯磺酰氯和三乙胺为试剂的脱溴现象，这表明在反应过程中形成良好离解的氯离子源是必要的。此外，还通过使用吡啶-亚硫酰氯作为试剂实现对二溴代双-γ-内酯的选择性脱溴。或者，

据报道在三乙胺和甲磺酰氯存在下四环二溴代双-γ-内酯的选择性脱溴。甲磺酰氯和三乙胺对于脱溴过程都是必不可少的。建议通过亲电子溴的卤代取代进行还原。据认为，该反应中的嗜盐菌的来源是氯化三乙基（甲磺酰基）铵。在二溴双-γ-内酯中不存在以甲苯磺酰氯和三乙胺为试剂的脱溴现象，这表明在反应过程中形成良好离解的氯离子源是必要的。此外，还通过使用吡啶-亚硫酰氯作为试剂实现对二溴代双-γ-内酯的选择性脱溴。或者，