摘要
以醋酸三乙铵离子液体为溶剂,硫酸亚铁为催化剂,过氧化氢为氧化剂,研究了甲苯分子中两种不同类型C—H键的选择性活化规律,优化了甲苯环C—H键优先活化的实验条件。发现在低温（40~60℃）和酸性的醋酸三乙铵离子液体（pH3~4）中反应,甲苯优先发生环羟基化反应生成甲基酚,且其深度氧化被极大抑制,获得甲基酚选择性大于60.0%,最高可达71.8%。甲苯环羟基化反应较侧链氧化反应更易受到过氧化氢浓度变化的影响,较高的过氧化氢浓度有利于环羟基化反应的进行。
The selective oxidation of toluene with ferrous sulfate and hydrogen peroxide in triethylammonium acetate ionic liquid（IL）has been studied.The reaction conditions for the preferential ring-hydroxylation of toluene have also been optimized.It is found that low temperature（40-60 ℃）and acidic triethylammonium acetate IL（pH 3-4）favor the selective activation of ring C—H bonds of toluene.The over-oxidation of cresols to quinones is significantly suppressed in the acidic media.The selectivity to cresols is above 60.0%,with a maximum value of 71.8%.A higher concentration of hydrogen peroxide in the media is advantageous for the ring-hydroxylation than for side-chain oxidation.
出处
《中国科技论文》
CAS
北大核心
2013年第9期874-877,共4页
China Sciencepaper
基金
高等学校博士学科点专项科研基金资助项目(20090181120063)
国家自然科学基金资助项目(20901053)
关键词
物理化学
C—H键选择性活化
醋酸三乙铵
离子液体
甲苯
环羟基化
physical chemistry
selective activation of C—H bond
triethylammonium acetate
ionic liquid
toluene
ring-hydroxylation
