1种新的对甲氧基苯甲醛的合成方法

A New Synthetic Method for P-methoxy Benzaldhyde

[目的]研究1种新的对甲氧基苯甲醛的合成方法。[方法]选用选择性好、对环境无害的过碳酸钠作氧化剂,通过对催化剂的筛选,筛选出对甲基苯甲醚液相选择氧化的Co-Cu-Br催化体系,考察了添加不同离子对催化对甲基苯甲醚氧化合成对甲氧基苯甲醛的影响。[结果]Co(Ac)2-Cu(Ac)2-KBr复合体系具有较好的催化效果,在HAc溶剂,常压,65℃,n(Co)∶n(Cu)∶n(Br)=5∶1∶1,n(底物)∶n(Co+Cu+Br)=100∶1的条件下,转化率可达46.10%,生成对甲氧基苯甲醛的选择性为69.50%。相同的试验条件下,在反应体系中添加适量的Zr4+或Hf4+,对甲基苯甲醚转化率可达60%左右,对甲氧基苯甲醛选择性为60%左右。同时添加Zr4+和Hf4+,当CZr4+=0.0320 mol/L,CHf4+=0.0880 mol/L时,底物转化率和醛选择性均约为70%。[结论]该方法是一种利于环保、节能,操作简单、安全的合成方法,具有较高的工业价值。

[Objective] The propose was to study a new synthetic method for p-methoxy benzaldhyde.[Method] Selecting the sodium percarbonate with good selectivity and harmless to the environment as the oxidant,the Co-Cu-Br catalytic system that could oxidize selectively in the p-methylanisole liquid phase could be screened through the screening of catalysators and the effects of adding different ions on catalyzing p-methyl anisole for synthesizing p-methoxy benzaldhyde was investigated.[Result] The Co（Ac）2-Cu（Ac）2-KBr composite catalytic system had better catalyzing effect.Under the reaction conditions as： t=65 ℃,normal atmosphere,n（Co）∶n（Cu）∶ n（Br）=5∶1∶1,n（substrate）∶n（Co＋Cu＋Br）=100∶1,acetic acid solvent,catalyst stirring time of 3 h,reaction time of 4 h,the conversion of p-methyl anisole and the selectivity to p-methoxy benzaldhyde were 46.10% and 69.50% resp.Under same experiment conditions,when Zr4＋or Hf4＋ with suitable amount was added into the Co（Ac）2-Cu（Ac）2-KBr catalytic system,the conversion of p-methyl anisole and the selectivity to p-methoxy benzaldhyde all could be increase to about 60%,and when Zr^4＋and Hf^4＋ were all together added into the catalytic system,under the same reaction conditions and CZr^4＋=0.032 0mol/L,CHf^4＋=0.088 0 mol/L,all the conversion of p-methyl anisole and the selectivity to p-methoxy benzaldhyde could reach 70% approximately.[Conclusion] This method was a kind of synthesizing method that had features of being beneficial to the environment,saving energy and the simple and safe operation,which had higher industrial value.