It was found that the ethoxycarbonyl derivatives of o-acylphenols were reduced to the corresponding o-alkylphenols by sodium borohydride under mild conditions ; the use of 3 molar equivalents of sodium borohydride was sufficient for this reduction. Various kinds of o-acylphenols (1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25 and 27) were reduced to the corresponding o-alkylphenols (2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 24, 26 and 28, respectively) in high yield by this method. o-acetylphenyl acetate (29) afforded o-ethylphenol (8) in better yield with sodium borohydride than ethyl o-acetylphenylcarbonate, but o-acetyl-phenyl p-toluenesulfonate (30) did not give 8.
研究发现,o-酰基
苯酚的乙氧基羧基衍
生物在温和条件下可被氢化
钠还原为相应的o-烷基
苯酚;使用3摩尔当量的氢化
钠即可完成该还原反应。各种类型的o-酰基
苯酚(1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25和27)通过这种方法被高产率还原为相应的o-烷基
苯酚(2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 24, 26和28)。o-乙酰基苯基
乙酸酯(29)在氢化
钠的作用下,相较于乙基o-乙酰基
苯基碳酸酯,能获得更高产率的o-
乙基苯酚(8),但o-乙酰基苯基对
甲苯磺酸酯(30)则未能得到8。