2 - 甲基- 2 - 羟基- 1 - 苯基- 1 - 戊酮的合成

首先以2 - 甲基戊酸、氯化亚砜合成了2 - 甲基戊酰氯;其次, 以无水三氯化铝为催化剂, 苯与2 - 甲基戊酰氯反应合成了2 - 甲基- 1 - 苯基- 1 - 戊酮;最后在氢氧化钠水溶液中, 以四氯化碳为氯化试剂, 四丁基溴化铵作相转移催化剂, 2 - 甲基- 1 - 苯基- 1 - 戊酮直接氯代和水解制得2 - 甲基- 2 - 羟基- 1 - 苯基- 1 - 戊酮。结果表明, 当2 - 甲基戊酸与二氯亚砜的物质的量比为1. 0 ∶1. 5、二氯亚砜的滴加温度为40 ℃、滴加时间1. 5 h 、反应时间2. 5 h 、无水三氯化铝的质量18. 5 g 、苯的用量45 m L 和2 - 甲基戊酰氯的滴加时间0. 5 h 时, 2 - 甲基- 1 - 苯基- 1 - 戊酮的收率为92. 7%;当2 - 甲基- 1 - 苯基- 1 - 戊酮与四氯化碳的物质的量比为1. 0 ∶1. 8 、四丁基溴化铵用量为6 g 、质量分数为20 %的NaOH 溶液、反应时间为5 h 时, 2 - 甲基- 2 - 羟基- 1 - 苯基- 1 - 戊酮的收率为91. 2% 。通过元素分析、红外光谱分析、质谱分析对产品进行了结构表征。

Synthesis of 2-Methyl-2-Hydroxy-1-Phenyl-1-Pentanone

First , 2 - methyl isocaproy l chloride was prepared by 2 - methylvaleric acid and thionyl chloride. Second, 2 - methyl- 1 - pheny l - 1 - pentanone was synthesized with benzene and isocaproyl chloride in the presence of anhydrous aluminumchloride as a catalyst. The n, 2 - methy l - 2 - hydroxy - 1 - pheny l - 1 - pentanone was prepared by chlorination and hydrolysiswith 2 - methyl - 1 - pheny l - 1 - pentanone in the presence of NaOH and CCl4 as chlorinating agent and tetrabutyl ammoniumbromide as the phase transfer catalyst. The result shows :w hen n(2 - methylvaleric acid)/n(thionyl chloride) is 1. 0 ∶1. 5,dropwise temperture and time of thionyl chloride is 40 ℃ and 1. 5 h respectively , reaction time is 2. 5 h, anhydrous aluminumchloride is 18. 5 g , benzene is 45 mL, dropwise time of isocaproyl chloride is 0. 5 h , the yield of 2 - methy l - 1 - pheny l - 1 -pentanone is 92. 7 %;when n(2 - methy l - 1 - pheny l - 1 - pentanone)/n(CCl4) is 1. 0 ∶1. 8 , tetrabutylammonium bromide is6 g , mass fraction of sodium hydroxide is 20 % and reaction time is 5 h , the yield of 2 - methyl - 2 -hydroxy - 1 - pheny l - 1- pentanone can be up to 91%. The structure of the product was characterized by elemental analysis, IR and MS.