首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
以2,4-二硝基氯苯为起始原料,依次经甲胺化,选择性还原,N-酰化,环合,催化氢化,N-二羟乙基化,O-甲磺酰化,氯置换,酸化水解和成盐等10步反应合成盐酸苯达莫司汀,其结构经1H NMR确证,总收率48.4%,纯度99.5%。  相似文献   

2.
孙婷  刘涛  刘传志 《广州化学》2010,35(4):12-16,23
采用Zn-饱和甲酸铵溶液、Zn-饱和苯甲酸铵溶液还原体系,从偶氮苯制备氢化偶氮苯。Zn-饱和甲酸铵溶液还原体系的优化反应条件为:偶氮苯/锌物质的量比为1∶3(偶氮苯2.5 mmol),饱和甲酸铵溶液1.0 mL,反应时间5 min,产率87.5%。Zn-饱和苯甲酸铵溶液还原体系的优化反应条件为:偶氮苯/锌物质的量比为1∶3(偶氮苯0.625 mmol),饱和苯甲酸铵溶液2.0 mL,反应时间3 min,产率86.4%。  相似文献   

3.
研究优化电解还原对硝基苯胂酸(p-A)合成对氨基苯胂酸(p-ASA)的工艺条件.实验表明:硫酸浓度、添加剂量、反应温度、投料量等工艺参数对合成产率有显著影响.初步得出比较适宜的电解合成条件为:硫酸浓度10%(bymass,下同)、添加剂量1%(bymass)NaCl、反应温度80℃、投料量71.4g/L、电流密度10A·dm-2.在上述工艺条件下,电解合成产率可达65.8%.  相似文献   

4.
巨新春  张群  孙淑婷  王博 《合成化学》2019,27(6):411-417
以邻苯二胺为配体,制备了一种新型的纳米钯催化剂(Pd-NPs),其结构经TEM, FT-IR, XRD, XPS, EA和ICP OES表征。常温常压下,以H2作氢源,水为溶剂,研究了Pd-NPs对芳香醛选择性还原反应的影响,产物结构经1H NMR和13C NMR确证。以苯甲醛的还原反应作为模板反应,研究了配体、催化剂用量和反应时间对苯甲醇产率的影响。结果表明:在最佳反应条件(配体为邻苯二胺,Pd-NPs用量10 mol%,反应5 h)下,苯甲醇产率达99%。  相似文献   

5.
谢宇  胡金刚  贾杰  洪小伟  魏娅 《有机化学》2010,30(2):282-284
以对苯二酚为原料经羟基的甲基化、傅克酰基化、肟化、肟基还原、酮胺氢化5步反应合成了盐酸甲氧明, 中间体和目标产物经核磁共振氢谱、红外光谱及元素分析仪确证了其化学结构, 总收率为37.6%. 与传统盐酸甲氧明工艺相比, 该工艺反应条件温和、简便、经济、产率高及对环境友好.  相似文献   

6.
乙氧基苯是一种重要的有机合成中间体,应用于农药、染料、化学试剂,药品如非那西丁、氢化可的松、醋酸泼尼松等的合成,本文研究了利用相转移催化反应在不同的催化剂反应条件下,合成中间体乙氧基苯,在氢氧化钠存在下,苯酚与硫酸二乙酯于60-65℃反应3h条件下合成乙氧基苯,产品产率达90%以上。对不同的催化剂的使用和反应时间进行了条件优化,对产品乙氧基苯的IR谱图、NMR谱图进行了确认和详细的分析.  相似文献   

7.
崔玉民  范少华等 《化学通报》2001,64(11):715-717,726
从邻硝基氯苯合成3,3‘-二氯-4,4‘-二氨基联苯:邻硝基氯苯(a)在1,4-萘醌催化下与CH2O反应得到2,2‘-二氯氧化偶氮苯(b),产率91.0%;b在Al-Ni合金及1,4-萘醌催化下与水合肼反应得到2,2‘-二氯氢化偶氮苯(c),产率97.0%;c在盐酸中重排得到d,产率96.9%。d的总产率达85.5%,含量97.7%。  相似文献   

8.
报道了一种简便高效的苯并咪唑类衍生物的水相合成新方法, 合成了兼具离子液体和二醋酸碘苯双重特点的咪唑盐二醋酸碘苯. 以水为溶剂, 在咪唑盐二醋酸碘苯促进下, 通过邻苯二胺或4-甲基邻苯二胺与各种芳醛室温氧化环合, 一步合成了13种苯并咪唑类衍生物, 反应时间25~45 min, 反应产率92%~98%. 用核磁共振、红外光谱、质谱和元素分析对产物的结构进行了表征, 提出了可能的反应机理. 该合成方法具有底物适用范围广、反应条件温和、反应速度快、反应产率高及氧化剂对应的还原产物可回收利用等优点, 是一种环境友好的绿色合成方法.  相似文献   

9.
以对苯二酚为基本原料,通过改进的甲氧基化、氯甲基化、锍化3个反应合成,得到(2,5-二甲氧基对苯乙炔)单体双锍盐2,5-二甲氧基对苯二苄氯锍盐,且产率达84%,并对每步反应的合成条件及原因进行了解释,运用色谱/质谱联用仪和核磁共振仪对每步产物进行了表征  相似文献   

10.
3,3′-二氯-4,4′-二氨基联苯的合成   总被引:4,自引:0,他引:4  
崔玉民  范少华  单德杰 《化学通报》2001,64(11):715-717
从邻硝基氯苯合成 3,3′ 二氯 4 ,4′ 二氨基联苯 :邻硝基氯苯 (a)在 1 ,4 萘醌催化下与CH2 O反应得到 2 ,2′ 二氯氧化偶氮苯 (b) ,产率 91 0 % ;b在Al Ni合金及 1 ,4 萘醌催化下与水合肼反应得到2 ,2′ 二氯氢化偶氮苯 (c) ,产率 97 0 % ;c在盐酸中重排得到d ,产率 96 9%。d的总产率达 85 5 % ,含量97 7%  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

13.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

17.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

18.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号