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1.
程晓红  傅长金   《中国化学》2007,25(11):1762-1765
本文从商品化的间溴苯甲醚和对甲氧基苯甲醛出发,通过傅-克酰基化反应、串联的羟醛缩合及1,4-迈克尔加成反应,得到三芳基取代的1,5-二酮,然后用查尔酮(Chalcone)作氧化剂,二酮与BF3.Et2O 反应形成吡喃鎓盐,再与苯基乙酸钠盐缩合得到芳香二溴代衍生物,产物的DMA溶液在DBU和钯催化剂的作用下,160°C 加热12 h进行脱卤化氢环化反应, 生成四甲氧基取代的二苯并并四苯(DBN)类衍生物。并报道了产物的晶体结构和在溶液中的聚集效应。  相似文献   

2.
Photolysis reaction of dibenzo[a,d]cycloheptene dimer 3 provides three dibenzo[a,d]cycloheptyl dimers 4 , 5 and 6 under different irradiation conditions via the intramolecular degradative cyclodimerization. A tetracyclic benzo[4,5]cyclohepta[1,2,3‐de]naphthalene core is also synthesized.  相似文献   

3.
A simple, convenient, and efficient method for the formation of functionalized dibenzo[b,f]oxepins and their analogs bearing both electron‐donating and electron‐withdrawing groups has been developed via a one‐pot cascade reaction. Most starting materials are commercially available 2‐(2‐hydroxyphenyl)acetonitriles and 2‐haloarylaldehydes. The procedure makes use of Cs2CO3 as the base, and DMF as solvent under copper‐assisted/copper‐free conditions. The reaction has a comprehensive group tolerance for substrates. Most of the reactions were complete within 1 h in good‐to‐excellent yields, and the reaction temperatures were relatively low. The protocol could be scaled up to grams without lowering the yield. A reaction mechanism was also proposed.  相似文献   

4.
The twisted aromatics, functional dibenzo[d,f][1,3]dioxepine derivatives were synthesized in high yields from reactions of 5,5'-dibromo-2,2'-biphenol with corresponding ketal or ketone compounds under acid catalysis. The structures of these compounds were characterized by ^1H NMR, elemental analysis, UV-Vis absorption spectrum and X-ray diffraction analysis. The conformation of O--C--O bridged biphenyl derivatives with varied substitute groups on 6,6'-position was studied by X-ray crystallography and force-field simulation. The result of calculations by UNIVERSAL 1.02 force field in Cerius2 package(4.6) indicates that dibenzo[d,f][1,3]dioxepine derivatives show twisted conformations and the twisted angle between the phenyl rings is about 40°, which is accordant with the result from crystal structure determination, though the obtained angles in the crystal of dibenzo[d,f][1,3]dioxepine derivatives with the varied substitute groups on 6,6'-position are shown to be slightly shifted to 40° owing to intermolecular interactions in crystal stacking. DSC studies exhibit that the substitute groups on 6,6'-position can induce a large variation of endothermic peaks ranging from 80 to 135 ℃. The conjugated polymers based on dibenzo[d,f][1,3]dioxepine derivatives, which have ultraviolet emitting with a quantum efficiency of 10%, were obtained by Yamamoto coupling.  相似文献   

5.
Cheng XH  Höger S  Fenske D 《Organic letters》2003,5(15):2587-2589
[structure: see text] 1,3-Bis(2-bromophenyl)-2,5-diphenylbenzenes are readily available by the condensation of phenylacetates with the corresponding pyrylium salts and undergo a palladium-catalyzed dehydrohalogenation to give functionalized dibenzo[fg,op]naphthacenes.  相似文献   

6.
7.
8.
以两种不同取代的2-氨基二苯甲酮为原料,氯苯为溶剂,BF3-Et2O为脱水剂,通过分子间脱水一步环化缩合制备非对称二苯并[b,f][1,5]二氮杂环辛四烯衍生物。运用HPLC监控反应过程,优化合成工艺,得到最佳反应条件为:等物质的量的两种不同取代2-氨基二苯甲酮和BF3-Et2O,在氯苯中回流反应12 h。化合物4a^4c为新化合物,其结构经1H NMR,13C NMR和MS(ESI)表征。  相似文献   

9.
The syntheses of the selenium containing heterocycles dibenzoselenophene ( 1 ≡ biphenSe) and dibenzo[1,2]diselenine ( 2 ≡ biphenSe2) were optimized. The halogenation reactions of 1 and 2 with XeF2, SO2Cl2, Br2 and I2 were performed and the corresponding products characterized. In the case of 1 , the selenium(IV) dihalogenides, biphenSeF2 ( 3 ), biphenSeCl2 ( 4 ), biphenSeBr2 ( 5 ), and the adduct biphenSe·I2 ( 6 ), were isolated and identified. The extremely sensitive selenium(IV) difluoride 3 slowly formed significant amounts of an adduct with HF of the corresponding selenium(IV) oxide biphenSeO·HF ( 3a ) upon storage in glass vessels at low temperatures. In the case of 2 , the selenium(IV) trihalogenides, biphen(SeHal3)2 (Hal = F, Cl, Br), were found to be extremely labile (Hal = F) or not detectable (Hal = Cl, Br). Instead, as decomposition products, the selenium chloride species Se2Cl2, SeCl4 and 1 were detected. In the case of Hal = I, the stable adduct biphenSe2·I2 ( 7 ) was isolated. In addition to characterization by multinuclear NMR spectroscopy, several molecular structures of biphen‐selenium substituted halogenides were determined.  相似文献   

10.
盘状液晶分子由稠环芳核和围绕的多条柔性链构成, 具有独特的自组装有序超分子结构、半导体性质和光学性质. 其可通过溶液或喷墨打印技术加工成为光电子薄膜器件, 具有低成本优势. 通过Suzuki-Miyaura交叉偶联和Scholl氧化环化策略, 合成了一系列新的具有苯并䓛结构的非对称酸酐、羧酸酯、酰亚胺和苯并咪唑稠环衍生物, 并对其液晶性和光物理性质进行了详细研究. 通过偏振光学显微镜(POM), 差示扫描量热法(DSC)和小角度X射线散射(SAXS)测试表明, 这些极性盘状化合物自组装堆积呈六方柱状(Colhex)液晶相, 其中, 最宽的液晶温度范围达206 ℃. 官能团和共轭体系大小决定了相变温度和液晶范围. 荧光测试结果表明, 化合物溶液中绝对量子产率高达34%, 根据官能团不同, 这些化合物发蓝、绿和红光. 借助密度泛函理论(DFT)计算, 解释了该系列极性盘状液晶分子发光性质的差异. 基于本工作的合成方法, 从萘酸酐原料出发为构建结构多变、性质丰富的π-共轭(杂环)芳烃盘状液晶化合物提供了新途径.  相似文献   

11.
It was shown that 6-acyl-5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-ones are formed when 5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-one is heated with the chlorides and anhydrides of carboxylic acids in the presence of bases (pyridine, NaOAc) while 5-acyl-5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-ones are formed in the presence of NaH. In the presence of NaH 6-acyl-5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-ones form the products from acylation and alkylation at position 5. The action of heat on 5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-one in oxalyl chloride leads to 7H,8H-2a,7a-diazacyclopenta[fg]naphthacene-1,2,8-trione. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 741–750, May, 2008.  相似文献   

12.
Summary A novel synthesis to prepare dibenzo-8-quinolizinones8 is reported using the intramolecular cyclisation of the benzylated Reissert compounds6 for the key step. Methylation of8 by methyllithium gives partial deoxygenated coralynes10 which in turn can be reduced by NaBH4 yielding the 8-methyltetrahydro-protoberberines11. The structures are assigned by NMR-spectroscopy.
  相似文献   

13.
以邻氨基二苯甲酮为原料,经自身缩合环化合成了3种二苯并[1,5]二氮杂芳辛四烯衍生物(1a~1c);以邻苯二甲酸酐和溴苯为原料经傅-克反应制得中间体2-(4-溴苯甲酰溴)苯甲酸(M1);M1经叠氮化后自缩合制得6,12-二(4-溴苯基)二苯并[b,f][1,5]二氮杂环辛四烯(1d);以邻氨基苯甲酸甲酯为原料,经自身缩合环化制得中间体二苯并[b,f][1,5]二氮杂环辛四烯-6,12(5H,11H)-二酮(M2);M2经氯化合成6,12-二氯二苯并[b,f][1,5]二氮杂环辛四烯(1e),化合物1a~1e的结构经~1H NMR,~(13)C NMR和ESI-MS表征,其中化合物1c为新化合物。利用超临界色谱(SFC)技术对化合物1a~1e实现了手性拆分,获得5对具有高旋光度的光学活性异构体(ee99%)。  相似文献   

14.
While reviewing the chemistry of cyclopentadienone derivatives and aza isoskeletal analogs of dibenzo[a,c]anthracene, additional molecular orbital (MO) and spectroscopic results and insights are presented. The MO tendency for coplanarity of phenyl substituents on benzenoids is demonstrated. Perpendicularly oriented phenyl substituents resulting from steric interactions strongly shield appropriately situated protons in NMR spectra. The principles of alternating polarity and parallel correspondence in conjunction with MO methods are used to relatively order aza arene isoskeletal analogs according to their chemical properties. Since less than 1.87% of the isoskeletal analogs of benzo[a,c]-anthracene have been reported, this summary work will help one to forecast the major chemical properties of those not yet synthesized.A preliminary account of this work was presented at the 23rd ACS Midwest Regional Meeting, University of Iowa, Iowa City, Nov. 17, 1988  相似文献   

15.
Tapas Ghosh 《合成通讯》2018,48(11):1338-1345
Nickel-catalyzed regioselective construction of dibenzo[c,f]oxocine framework with tri-substituted exo-cyclic alkenes have been obtained through an efficient implementation of reductive-Heck protocol. This cost effective, efficient methodology has been demonstrated for the synthesis of various dibenzo[c,f]oxocine derivatives with moderate to good yields.  相似文献   

16.
The lower-rim formylated azacalix[4]pyrimidine underwent transannular Friedel–Crafts and dehydrogenative cross coupling reactions to afford, respectively, 2,4,5,7-tetraaza-9,10-dihydroacridine and -dihydroacridin-9-one containing azacalix[3]aromatics. Dihalogenation of the later compound produced resolvable inherently chiral azacalix[3]aromatics.  相似文献   

17.
赵邦屯  周振  颜振宁 《有机化学》2009,29(10):1682-1686
在碳酸钾存在下, 对叔丁基硫桥杯[4]芳烃(1)分别与端基二溴代烷和碘甲烷反应, 生成硫桥杯[4]芳烃衍生物2~4. 含端基溴代的硫桥杯[4]芳烃衍生物2和4分别与2-巯基苯并噁唑在碳酸钾存在下反应, 生成硫桥杯[4]芳烃衍生物5a~5d. 通过1H NMR, 13C NMR, IR, MS和元素分析等手段对产物进行了表征. 同时, X射线分析确定了硫桥杯[4]芳烃5b的晶体结构.  相似文献   

18.
A facile synthetic approach toward thiacalix[n]thiophene homologues (n=4–6) is presented herein. Pd‐catalyzed coupling of 2,5‐dibromothiophene derivatives with stannyl sulfide gave various thiacalix[n]thiophenes in good yields. The optical and electrochemical properties of the produced cavitands were investigated. Furthermore, gelation was observed in some solvents.  相似文献   

19.
张宝华  史兰香 《应用化学》2018,35(11):1331-1334
针对二苯并[d,f][1,3]二噁烷传统制备方法中易产生二羟基联苯乙烯副产物的缺点,本文以路易斯酸性胍盐离子液体为催化剂,2,2'-二羟基联苯和端基炔为原料,高区域选择性的合成了二苯并[d,f][1,3]二噁烷,收率39%~84%。 本方法适用于各种端基炔。路易斯酸性胍盐离子液体循环利用5次,活性不变。  相似文献   

20.
New solid-matrix phosphorescence (SMP) methods for (±)-anti-DB[a,l]PDE-DNA adducts and B[e]P were developed. The methods can be used to detect and characterize (±)-anti-DB[a,l]PDE-DNA adducts and B[e]P by employing SMP spectra, intensities, and lifetimes acquired with the heavy-atom salt, TlNO3, on Whatman 1PS paper. With the SMP data, a number of photophysical parameters were calculated such as biexponential SMP decay curves, pre-exponential factors, and fractional contribution to SMP decay curves. The SMP results were compared with earlier SMP data for (±)-anti-BPDE-DNA adducts and tetrol I-1. The SMP results show that small molecular-weight compounds like B[e]P can be readily detected and characterized by SMP. For example, the limit of detection for B[e]P was 0.60 pmol. Comparison of the SMP properties of the (±)-anti-DB[a,l]PDE-DNA adducts with earlier SMP data for the (±)-anti-BPDE-DNA adducts showed major differences in the SMP spectra, intensities, and lifetimes. The methods developed are important for the comparison of the SMP properties of different diol epoxides of PAH bonded to DNA.  相似文献   

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