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甲基芳烃的侧链溴化新方法研究 被引量:5
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作者 申理滔 陈红飙 林原斌 《有机化学》 SCIE CAS CSCD 北大核心 2010年第2期272-275,共4页
溴苄类化合物在医药、农药和染料等领域有广泛的应用,在以往的报道中由甲基芳烃制备溴苄类化合物的方法都是采用自由基的历程进行的.报道了一种以甲基芳烃与三溴化硼直接反应采用非自由基的历程制备系列溴甲基芳烃的新方法.该方法反应... 溴苄类化合物在医药、农药和染料等领域有广泛的应用,在以往的报道中由甲基芳烃制备溴苄类化合物的方法都是采用自由基的历程进行的.报道了一种以甲基芳烃与三溴化硼直接反应采用非自由基的历程制备系列溴甲基芳烃的新方法.该方法反应条件温和、收率高、选择性好.在考察电子效应和位阻效应时发现:该方法对不同取代基的底物适应范围广,带推电子取代基对反应有利;取代基位阻有一定影响但是没有吸电子基团显著,吸电子基团降低产率.同时,在研究溶剂、温度、三溴化硼用量和时间对反应的影响时找到了最佳反应条件. 展开更多
关键词 三溴化硼 溴化 甲基芳烃 溴甲基芳烃
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Ag掺杂V2O5/TiO2催化氧化3-甲基吡啶脱甲基反应 被引量:3
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作者 胡小波 朱秋莲 +2 位作者 刘华彦 陈银飞 卢晗锋 《精细化工》 EI CAS CSCD 北大核心 2015年第12期1369-1375,共7页
采用浸渍法制备了不同Ag掺杂的Ag-V/TiO_2催化剂,考察其催化部分氧化3-甲基吡啶脱甲基性能。采用X射线衍射(XRD)、X射线光电子能谱(XPS)、H_2程序升温还原(H_2-TPR)对催化剂进行了表征。结果表明,Ag的掺杂提高了催化剂中表面氧和+4价态... 采用浸渍法制备了不同Ag掺杂的Ag-V/TiO_2催化剂,考察其催化部分氧化3-甲基吡啶脱甲基性能。采用X射线衍射(XRD)、X射线光电子能谱(XPS)、H_2程序升温还原(H_2-TPR)对催化剂进行了表征。结果表明,Ag的掺杂提高了催化剂中表面氧和+4价态的钒物种的含量,加快了催化剂的还原过程,提高了氧化活性,Ag主要以单质的形态存在。3-甲基吡啶氧化反应表明,Ag的掺杂使反应选择性发生变化,主产物由烟酸变成吡啶,当Ag的掺杂量为2%(Ag相对于V_2O_5的摩尔分数)时,甲基的脱除率最好,摩尔产率为80.1%,选择性84.7%,烟酸几乎不产生。该脱甲基氧化反应的过程是V^(4+)/V^(5+)(O_2^-)在攻击侧链的C—H键的同时,Ag在O_2的作用下形成了含有亲电子型氧(O^-和O_2^-)的Agp+O活性物种,攻击侧链和苯环相连的C—C键,共同作用将侧链的甲基以氧化形成CO_x的形式脱除。 展开更多
关键词 甲基芳香烃 脱甲基 催化 氧化 钒钛催化剂 催化与分离提纯技术
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Electrochemical Umpolung Enabled Radical-Radical Cross-Coupling Between Electron-Deficient Methylarenes and Aldehydes 被引量:1
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作者 Fei Lian Kun Xu Chengchu Zeng 《CCS Chemistry》 CSCD 2023年第9期1973-1981,共9页
The electrochemical utilization of electron-deficient methylarenes for radical-radical cross-couplings remains very rare.Enabled by an umpolung strategy,the unprecedented electrochemical cross-coupling of electron-def... The electrochemical utilization of electron-deficient methylarenes for radical-radical cross-couplings remains very rare.Enabled by an umpolung strategy,the unprecedented electrochemical cross-coupling of electron-deficient methylarenes with aldehydes was developed.The paired electrolysis simultaneously generated electron-deficient benzylic radicals and ketyl radicals at both electrodes,which then underwent radical recombination,governed by polarity matching and persistent-radical effect(PRE)to afford functionalized alcohols that are not easily accessible by other methods.This protocol features catalystand external redox agent-free conditions and a formal 100%atom economy.Mechanistic studies support the radical-radical cross-coupling pathway. 展开更多
关键词 paired electrolysis ketyl radical UMPOLUNG radical-radical cross-coupling methylarene ALDEHYDE
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Efficient synthesis of 2-arylquinazolines via copper-catalyzed dual oxidative benzylic C–H aminations of methylarenes 被引量:1
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作者 Li-Yan Liu Yi-Zhe Yan +1 位作者 Ya-Jie Bao Zhi-Yong Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第10期1216-1220,共5页
A novel copper-catalyzed dual oxidative benzylic C–H aminations of methylarenes with 2-aminobenzoketones in the presence of ammonium acetate was developed. This reaction represents a new avenue for 2-arylquinazolines... A novel copper-catalyzed dual oxidative benzylic C–H aminations of methylarenes with 2-aminobenzoketones in the presence of ammonium acetate was developed. This reaction represents a new avenue for 2-arylquinazolines with good yields. A key intermediate was detected and the kinetics isotope effect(KIE) indicated that C–H bond cleavage was the rate-determining step. 展开更多
关键词 Quinazolines Copper C–H aminations methylarenes
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Syntheses of amides via iodine-catalyzed multiple sp3 C-H bonds oxidation of methylarenes and sequential coupling with N,N-dialkylformamides 被引量:1
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作者 DU BingNan SUN PeiPei 《Science China Chemistry》 SCIE EI CAS 2014年第8期1176-1182,共7页
The oxidative coupling of methylarenes and N,N-dialkylformamides was developed, and the appropriate reaction conditions were established. By using I2 as the catalyst, and tert-butyl hydroperoxide(TBHP) as the oxidant,... The oxidative coupling of methylarenes and N,N-dialkylformamides was developed, and the appropriate reaction conditions were established. By using I2 as the catalyst, and tert-butyl hydroperoxide(TBHP) as the oxidant, the reaction provided N,N-dialkylamides or N-alkylamides with moderate yields via multiple sp3 C-H bonds activation of methylarenes in aqueous and metal-free conditions. 展开更多
关键词 oxidative coupling iodine-catalyzed methylarenes AMIDES
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