2-羟基-2-甲基-1-苯基丙酮的合成

以苯甲醛、镁、2 -溴丙烷、溴等为主要原料 ,经四步反应合成了光敏引发剂 2 -羟基 - 2 -甲基 - 1 -苯基丙酮。在 0°C时 ,将 1 6.5g苯甲醛滴加到由 4g Mg和 2 0 .6g2 -溴丙烷制得的 Grignard试剂中 ,在室温下搅拌 0 .5h,得到 2 0 .5g异丙基苯甲醇。将 2 5g K2 Cr2 O7、1 1 0 m L水和 2 0 m L浓H2 SO4 的混合液加入由 90 m L氯仿、5m L新洁而灭和 35g异丙基苯甲醇组成的混合液中 ,加完后 ,在室温下继续搅拌 2 h,得到 2 9.5g异丙基苯甲酮。在 65～ 75°C,将 32 .5g Br2 和 30 m L四氯化碳滴加到 60 m L CCl4 、1 5m L醋酸和 2 8.5g异丙基苯甲酮中 ,在温度不超过 70°C时搅拌 3h,得到α-溴代异丙基苯甲酮。1 0 gα-溴代异丙基苯甲酮、32 m L质量分数为 1 0 %的 Na OH溶液及 5m L新洁而灭 ,加热回流 3h,得到 6.8g 2 -羟基 - 2 -甲基 - 1 -苯基丙酮。

Synthesis of 2-Hydroxy-2-methyl-1-propiophenone

2-Hydroxy-2-methyl-l-propiophenone was synthesized in four steps with benzaldehyde, 2-bromopropane and bromine as main raw materials. 16.5 g Benzaldehyde was added dropwise at 0 ℃ to a Grignard reagent from 4 g Mg and 20. 6 g 2-Bromopropane, and the mixture stirred 0. 5 h at room temperature, yield, 20. 5 g isopropylphenylcarbinol ( I ). A mixture of 25 g K2Cr2O7, 110 mL H2O and 20 mL concentrated H2SO4 was added slowly to 90 mL CHCl3, 5 mL benzalkonium bromide solution and 35 g( Ⅰ )under 30 ℃, the reaction mixture was stirred 2 h after added at room temperature, and produced 29.5 g isopropyl phenylketone ( Ⅱ ). 32 g Br2 and 30 mL CC14 was dropped to the mixture from 60 mL CCl4, 15mL HOAc and 28.5 g ( Ⅱ ) at 65 ℃～75 ℃, the reaction mixture was stirred 3 h at 70 ℃, yielded 38.5 g α-bromoisopropyl phenylketone ( Ⅱ ), 10 g ( Ⅱ ), 32 mL/10% (NaOH) and 5 mL benzalkonium bromide solution were refluxed 3 h, gave 6.8 g 2-hydroxy-2-methyl-1-propiophenone.