芳香胺是重要的医药中间体和化工原料,通过贝克曼重排反应合成芳香胺是一种有效途径。经典的贝克曼重排反应采用强酸催化,副反应多,并存在一定的环保问题。研究表明,采用SnCl_(2)·2H_(2)O催化芳香酮肟贝克曼重排反应能够实现芳香...芳香胺是重要的医药中间体和化工原料,通过贝克曼重排反应合成芳香胺是一种有效途径。经典的贝克曼重排反应采用强酸催化,副反应多,并存在一定的环保问题。研究表明,采用SnCl_(2)·2H_(2)O催化芳香酮肟贝克曼重排反应能够实现芳香酮向芳香胺的高效转化。进一步研究贝克曼重排反应中芳香环上取代基性质、催化剂、溶剂、温度等的影响因素表明,带有给电子基团的苯乙酮肟衍生物有利于该类衍生物迁移基团进行贝克曼重排反应,带吸电子基团的苯乙酮肟衍生物与之相反。对甲氧基苯乙酮在以乙腈为溶剂、SnCl_(2)·2H_(2)O为催化剂、82℃条件下,合成对甲氧基乙酰苯胺收率>92%。产物经1H NMR、13 C NMR、IR等表征。展开更多
For the aim of finding new available functional materials, a series of nitrogen heteroatom 2 β naphthylbenzoxazole molecules were designed based on the experiment and theoretical studies of 2 β naphthylb...For the aim of finding new available functional materials, a series of nitrogen heteroatom 2 β naphthylbenzoxazole molecules were designed based on the experiment and theoretical studies of 2 β naphthylbenzoxazole molecule. Geometry optimization of the 2 β naphthylbenzoxazole was carried out by using Hyperchem Molecular Mechanics plus MM+. The planar molecular structure was obtained. The quantum chemistry calculating method PPP SCF CI, which is specially available to treat electron spectrum, was applied to investigate each novel designed molecules. Their electronic structures were analyzed in detail, it shows that total π electron energy decreased linearly with the number of replaced nitrogen. Single nitrogen atom located in benzoxazole ring or naphthalene ring results in contrary changes of level difference of FMO; multiple nitrogen atoms located in different molecular positions will lead to polarization of extremum in the level difference of FMO; and 5 nitrogen heteroatoms reach the culmination. Considering other electronic structure information, some favorable designed molecules were identified.展开更多
文摘芳香胺是重要的医药中间体和化工原料,通过贝克曼重排反应合成芳香胺是一种有效途径。经典的贝克曼重排反应采用强酸催化,副反应多,并存在一定的环保问题。研究表明,采用SnCl_(2)·2H_(2)O催化芳香酮肟贝克曼重排反应能够实现芳香酮向芳香胺的高效转化。进一步研究贝克曼重排反应中芳香环上取代基性质、催化剂、溶剂、温度等的影响因素表明,带有给电子基团的苯乙酮肟衍生物有利于该类衍生物迁移基团进行贝克曼重排反应,带吸电子基团的苯乙酮肟衍生物与之相反。对甲氧基苯乙酮在以乙腈为溶剂、SnCl_(2)·2H_(2)O为催化剂、82℃条件下,合成对甲氧基乙酰苯胺收率>92%。产物经1H NMR、13 C NMR、IR等表征。
文摘For the aim of finding new available functional materials, a series of nitrogen heteroatom 2 β naphthylbenzoxazole molecules were designed based on the experiment and theoretical studies of 2 β naphthylbenzoxazole molecule. Geometry optimization of the 2 β naphthylbenzoxazole was carried out by using Hyperchem Molecular Mechanics plus MM+. The planar molecular structure was obtained. The quantum chemistry calculating method PPP SCF CI, which is specially available to treat electron spectrum, was applied to investigate each novel designed molecules. Their electronic structures were analyzed in detail, it shows that total π electron energy decreased linearly with the number of replaced nitrogen. Single nitrogen atom located in benzoxazole ring or naphthalene ring results in contrary changes of level difference of FMO; multiple nitrogen atoms located in different molecular positions will lead to polarization of extremum in the level difference of FMO; and 5 nitrogen heteroatoms reach the culmination. Considering other electronic structure information, some favorable designed molecules were identified.
