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1.
本文报道用KF/Al~2O~3作为碱催化剂,由水杨醛或2-羟基-1-萘醛分别和α-溴代乙酸酯、α-溴代苯乙酮、苄基氯、4,4'-二氯甲基联苯和1,5-二氯甲基萘等进行一锅化缩合反应,以38~89%的产率合成了14种芳并呋喃化合物。  相似文献   

2.
黄维垣  陈俭龙 《化学学报》1987,45(5):445-449
全氟烷基亚磺酸钠与溴水反应,得到全氟烷基磺酰溴(RfSO2Br),(但在乙腈,乙酸等有机溶剂中与溴反应,则生成溴代全氟烷.在碘化钾水溶液中,全氟烷基亚磺酸钠与碘反应,生成碘代全氟烷.α,α-二氯多币烷基亚磺酸钠在类似条件下与溴水反应,生成1-溴-1,1-二氯多氟烷,与碘在磺化钾水溶液中反应,生成1-碘-1,1-二氯多氟烷.1-溴-1,1-二氯多烷及1-碘-1,1-二氯多氟烷易对烯键加成,也可与连二亚硫酸钠在温和条件下发生亚磺化脱溴及脱碘反应.α,α-二氯二氟乙基亚磺酸钠在强酸中比较稳定,与强碱,氧化剂或还原剂发生反应,得到相应的产物.  相似文献   

3.
先以间二氯苯、氯乙酰氯和咪唑为原料合成β-( 1 -咪唑基 ) -2 ,4 -二氯 -α-苯乙醇 ( ) ,再以二卤苯为原料合成α-氯 -卤代乙苯 ( a~ d) ,然后 , 分别与 a~ d反应 ,生成α-(α -甲基 -卤代苄氧基 ) -β-( 1 -咪唑基 ) -2 ,4 -二氯乙苯硝酸盐 4个新化合物 ,产率分别为 66.8% ,78.5% ,76.8%和 81 .2 % ,新化合物的结构经元素分析 ,IR和 1H NMR表征  相似文献   

4.
2,4-二氯-α-氯代苯乙酮(1)与咪唑进行N-烷基化反应制得α-(1-咪唑基)-2,4-二氯苯乙酮(2);2经硼氢化钾还原得α-(1-咪唑基)-2,4-二氯苯基乙醇硼络合物(3);3直接与2,4-二氯氯苄进行O-烷基化反应合成了硝酸咪康唑(4). 2和4的结构经1H NMR, 13C NMR, IR和MS表征.用正交试验优化了合成2的工艺条件.在最佳反应条件[1=50 mmol, n(1) ∶ n(咪唑) ∶ n(三乙胺)=1.0 ∶ 1.2 ∶ 1.2,以苯为溶剂,于70 ℃反应1.5 h]下,2的收率达90.4%.4的总收率为68.2%.  相似文献   

5.
李再峰  罗富英 《应用化学》2001,18(6):473-476
E-、Z-2'-(1-咪唑基)-O-(α-甲基-二氯苄基)-2;4-二氯苯乙酮肟硝酸盐的合成与抑菌活性  相似文献   

6.
采用直接插入法制备了六氢吡啶(HHP)对α-Zr(HPO4)2·H2O(α-ZrP)的超分子插层复合物α-ZrP-HHP。用元素分析、红外光谱(IR)、X射线粉末衍射(XRD)和TG-DSC热分析等手段表征其结构,结果表明,六氢吡啶的插入使层间距增大了0·59nm,插入的六氢吡啶客体分子在主体底物中形成双分子层。研究了α-ZrP-HHP对含酚类物质(包括苯酚、4-氯苯酚、2,4-二氯苯酚)废水的吸附,结果表明,α-ZrP-HHP对上述三种酚类物质的吸附量呈如下规律:2,4-二氯苯酚>4-氯苯酚>苯酚。  相似文献   

7.
用手性α-氨基醇和原氯乙酸三乙酯作用得到的手性恶唑啉2a-2c和1,7-二氯- 12-冠-4反应,合成了带手性侧链的1,7-二氯-12-冠-4衍生物1a-1c,并将其铜配 合物运用于重氮醋酸酯对烯烃的不对称环丙烷化反应.  相似文献   

8.
以间二氯苯、氯乙酰氯和咪唑为原料 ,利用成肟和引入咪唑基顺序不同 ,首先合成了 E-,Z-2 -(1 -咪唑基 ) -2 ,4 -二氯苯乙酮肟 ( E、IZ) ,从二氯苯合成了 α-氯 -二氯取代乙苯 ( A、 B和 C) ,咪唑基 -二氯苯乙酮肟顺反异构体 ( Z、 E)分别与 α-氯 -二氯乙苯反应 ,生成 E-、Z-2 -(1 -咪唑基 ) -O-(α-甲基 -二氯苄基 ) -2 ,4 -二氯苯乙酮肟硝酸盐共 6种新化合物 ,产率为 5 7.5 %~ 64 .5 %,新化合物结构经元素分析、IR和 1H NMR表征 .初步实验表明 ,各化合物对水稻苗腐根有不同程度抑制活性 .  相似文献   

9.
本文报道了合成1α,2α-次甲基氯地孕酮醋酸酯5的改良法,即以17α-羟基黄体酮1为原料,用节杆菌和NBS-碳酸钙代替了有毒试剂四氯苯醌和二氯二氰苯醌脱氢,制得基关键中间体△~(1,4,6)-化合物3。从3经五步反应即得目的物5。  相似文献   

10.
本文对α-蒎烯与二氯卡宾的加成物3为原料,合成了马鞭草烯醇的类似物2,7,7-三甲基三环[4.1.1.0^2,^4]-5-辛醇及其酯类和醚类衍生物.  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.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

13.
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   

14.
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   

15.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

16.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

17.
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   

18.
19.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.  相似文献   

20.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

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