Electron-Deficient Benzo[de]isoquinolino[1,8-gh]quinoline Diamide π-Electron Systems

Synthetically versatile electron-deficient π-electron systems are urgently needed for organic electronics, yet their design and synthesis are challenging due to the low reactivity from large electron affinities. In this work, we report a benzo[de]isoquinolino[1,8-gh]quinoline diamide (BQQDA) π-electron system. The electron-rich condensed amide as opposed to the generally-employed imide provides a suitable electronic feature for chemical versatility to tailor the BQQDA π-electron system for various electronic applications. We demonstrate an effective synthetic method to furnish the target BQQDA parent structure, and highly selective functionalization can be performed on bay positions of the π-skeleton. In addition, thionation of BQQDA can be accomplished under mild conditions. Fine-tuning of fundamental properties and supramolecular packing motifs are achieved via chemical modifications, and the cyanated BQQDA organic semiconductor demonstrates a high air-stable electron-carrier mobility.     

Introduction of Benzo[h]quinoline and 1,10-Phenanthroline Subunits by Friedländer Methodology

An improved preparation of 8-amino-7-quinolinecarbaldehyde has been developed. The methyl group of 7-methyl-8-nitroquinoline may be oxidized to an aldehyde by treatment first with dimethylformamide dimethyl acetal followed by sodium periodate. Reduction with iron provides the amino aldehyde. An analogous sequence affords 1-amino-2-naphthalenecarbaldehyde. Friedl?nder condensation of the quinoline derivative with a series of acetylaromatics provides the corresponding 2-aryl-1,10-phenanthrolines. Condensation of either amino aldehyde with 1,3-diacetylbenzene or 2,6-diacetylpyridine provides the expected Friedl?nder product. Similar chemistry is described for reactions of the amino aldehydes with 1,4-diacetylbenzene, 4,4'-diacetylbiphenyl, 1,5-diacetylanthracene, 1,2,3,4,5,6,7,8-octahydroacridine-1,8-dione, and tetracyclo[6.3.0.0.(4,11)0(5,9)]undecane-2,7-dione (TCU-2,7-dione).     

Efficient Green Approach for the Synthesis of Spiro[indoline-3,4′-pyrazolo[3,4-b]quinoline]diones Using [NMP]H2PO4 and Solvatochromic and pH Studies

A mild and efficient protocol for the synthesis of spiro[indoline-3,4′-pyrazolo[3,4-b]quinoline]diones via a one-pot, three-component condensation of isatins, 1,3-dicarbonyls, and 5-amino-1-phenyl-3-methylpyrazole using [NMP]H₂PO₄ as a catalyst in EtOH/H₂O is described. The catalyst could be recycled and reused four times without significant loss of activity. Spiro[indoline-3,4′-pyrazolo[3,4-b]quinoline]diones with stabilized zwitter ionic resonance structures showed feasible application as new fluorescent probes and pH indicators. These chemosensors have a good wavelength shift and showed excellent sensitivity in the range of pH from 11 to 13.     

Photocycloaddition reaction between 7,7,9-trimethyl-6,7-dihydrofuro[3,2-f]quinoline and thymidine 5′-monophosphate

Quenching of the triplet state of 7,7,9-trimethyl-6,7-dihydrofuro[3,2-f]quinoline (FDHQ) by thymidine 5??-monophosphate disodium salt (TMP) has been observed in the water-alcohol solution with a bimolecular rate constant close in value to the diffusion-limited constant (2.2 × 10⁹ L mol^?1 s^?1). The products of the steady-state photolysis of a FDHQ-TMP mixture in the water-alcohol solution have been isolated by HPLC and identified by mass spectrometry. Four isomers with a molecular weight of 580 Da equal to the sum of the molecular weights of FDHQ + TMP and with identical mass spectra are the major products of the photolysis. The fragmentation of the molecular ion for all the isomers gives an ion with a weight of 340 Da, indicating the cleavage of the saccharide residue and the formation of the rigid cyclobutane cycle as a result of interaction between the double bond of the nitrogen- or oxygen-containing heterocycle of FDHQ in the triplet state and the C(5)=C(6) double bond of TMP. Diadducts have not been found in the photolysis products. Possible structures of the isomeric products of interaction of FDHQ with TMP have been considered.     

Rapid and efficient one-pot microwave-assisted synthesis of 2-phenylimidazo[1,2-a]pyridines and 2-phenylimidazo[1,2-a]quinoline in water–PEG-400

An effective, expeditious, environmentally benign one-pot synthesis of 2-phenylimidazo[1,2-a]pyridines and 2-phenylimidazo[1,2-a]quinoline from easily available starting materials as aromatic carbonyl compound, 2-amino pyridine, succinamide, and in situ generated α-iodo acetophenone in combination with green solvent PEG-400 and water (2:1) under microwave irradiation. The newly developed protocol with excellent yield of product in very short time of reaction by avoiding the use of lachrymatric α-chloro and α-bromocarbonyl compounds, volatile, toxic organic and hazardous solvents, reagents is the advantage of this research work. The final products were confirmed by their characterization data such as ¹H NMR, ¹³C NMR, high resolution mass spectrometry (HRMS) and were compared with its reported method.     

Photoinduced double proton transfer in water complexes of 1H-pyrrolo[3,2-h]quinoline and dipyrido[2,3-a:3′,2′-i]carbazole

Dual fluorescence is observed in water and water-containing solutions of 1H-pyrrolo[3,2-h]quinoline and dipyrido[2,3-a:3^′,2^′-i]carbazole. The low energy band is assigned to a product of excited state double proton transfer reaction, occurring in cyclic 1:1 complexes with water. Such complexes constitute only a small fraction of the ground state population. The majority of water complexes are not prone to phototautomerization, but are deactivated via a process that is not efficient in a non-hydrogen-bonded chromophore.     

Construction of new heteroacenes based on benzo[b]thieno[2,3-d]thiophene / quinoline or 1,8-naphthyridine systems using the Friedländer reaction

Two new classes of heteroacenes, namely benzo[4′,5′]thieno[2′,3′:4,5]thieno[3,2-b]quinolines and benzo[4′,5′]thieno[2′,3′:4,5]thieno[3,2-b][1,8]naphthyridines, have been formed using the Friedländer reaction to annulate the benzo[b]thieno[2,3-d]thiophene scaffold to quinoline or 1,8-naphthyridine fragments. In accordance with this synthetic strategy, benzo[b]thieno[2,3-d]thiophen-3(2H)-ones were treated with 2-aminobenzaldehydes or 2-aminonicotinaldehyde in the presence of pyrrolidine in glacial acetic acid at reflux to give the desired quinoline- or 1,8-naphthyridine-fused compounds, respectively. The optical and electrochemical properties of selected heteroacenes were determined.     

Synthesis of Spiro[benzo[h]chromene-4,3′-indoles] and Spiro[benzo[f]chromene-1,3′-indoles]

Russian Journal of Organic Chemistry - New spiro heterocycles, spiro[benzo[h]chromene-4,3′-indoles] and spiro[benzo[f]chromene-1,3′-indoles], have been synthesized in 50–60% yield...     

铁液中[Ce]-[O]-[S]沉淀图及其应用

选用近期实验所测较为准确的稀土-氧、稀土-硫、稀土-氧-硫体系的热力学数据建立了纯铁液中的[Ce]-[O]-[S]空间沉淀图。应用热力学理论计算了铁液中氧硫活度与生成的稀土夹杂物间的定量关系。确定了铁水初始氧硫活度与生成稀土夹杂物类型的关系,并验证了理论计算结果。     

Alkylation of 3‐Phenyl‐1H‐pyrazolo[4,3‐c] quinoline: Theoretical Analysis of Regioselectivity

The interaction of 3‐phenyl‐1H‐pyrazolo[4.3‐c]quinoline with alkylating agents in the presence of NaH leads mainly to N1‐substituted derivatives. The regioselectivity of the reaction has been studied using AM1 semi‐empirical calculations in the isolated molecule approximation.     

Self－assembly of Novel Hetero[3]rotaxane, [2]Rotaxanes and [2]Catenane

One linear template 13 and one cyclophane template 15, both incorporating two electron rich 1,4‐dialkoxybenzene units and one diamide unit, have been synthesized. By utilizing donor‐acceptor interaction and/or intermolecular hydrogen bonding assembling principles, one novel hetero[3]rotazane 22·4Cl, possessing one neutral and one tetracationic ring components, has been synthesized from 13, through neutral [2]rotaxane 21 as intermediate. With 15 as template, tetracationic [2]catenane 23·4PF₆ was assembled by using donor‐acceptor interaction, but no neutral [2]rotaxane could be obtained under the typical conditions of hydrogen bonding assembling principle. The interlocked supramolecular compounds have been characterized and their spectral properties are investigated.     

The pH-controlled[2]or [3]pseudorotaxanes based on stilbene dye SD⊂CB[7]

We studied characteristics of [2] or [3]pseudorotaxanes based on stilbene dye SD?CB[7] . In neutral or weak alkaline conditions, SD could be encapsulated inside the stilbene site of CB[7] with 1:1 stoichiometry, whereas, with the pH changing to acidity, the hydrogen bonding between the carboxyl group and the carbonyl of CB[7] maked another CB[7] molecule include into hexanoic acid site, these processes were confirmed by fluorescence spectra,UV–Vis spectra and 1H NMR.     

A convenient synthesis of 2-aryl substituted benzo[f] [1,2,4]triazolo[1,5-a]azepine derivatives

A convenient synthetic pathway to 2-aryl-5,6-dihydro-4H-benzo[f][1,2,4]triazolo[1,5-α]azepine derivatives 7 was developed. The synthesis was based on the cycloaddition of the 1,2,3,4-tetrahydronaphthalene a-acetoxy azo compounds 3 with Ar-CN in the presence of AlCl3 and the consecutive ring enlargement.     

[60]富勒烯[2＋2]环加成反应的研究进展

[2＋2]环加成反应是对C₆₀进行化学修饰的重要反应之一, 重点从[2＋2]环加成的典型反应、主要试剂及反应机理等方面进行了综述.     

[60]富勒烯[2＋3]环加成反应的研究进展

对[60]富勒烯[2＋3]环加成反应的研究进展进行了综述，并介绍了在环加成反应中使用的主要试剂及反应机理.     

Synthesis and Crystal Structure of exo-4-（3,4-Dichlorophenyl）-8-ethyl-3,3a,4,5,8, 12d-hexahydro-2H-furo[3,2-c]indolo[3,2-f]quinoline

The title compound exo-4-(3,4-dichlorophenyl)-8-ethyl-3,3a,4,5,8,12d-hexahydro-2H-furo[3,2-c]indolo[3,2-f]quinoline (C25H22Cl2N2O, Mr = 437.35) was synthesized and crystallized. The crystal belongs to tetragonal, space group I4(1)/a with a = 17.4903(3), b = 17.4903(3), c = 28.3403(5) , Z = 16, V = 8669.6(3) 3, Dc = 1.340 g·cm-3, μ(MoKɑ) = 0.319 mm-1, F(000) = 3648, R = 0.0429 and wR = 0.711 for 2714 observed reflections I > 2σ(I). X-ray analysis reveals that atoms C(1), C(2), C(3), C(4), C(5) and N(1) on the new pyridine ring are slightly distorted, forming a distorted boat conformation.     

Cu-catalyzed dehydrogenative C?O arylation for the synthesis of 6-methyl benzofuro[3,2-c] quinoline derivatives

A novel strategy for the synthesis of 6-methyl benzofuro[3,2-c] quinoline derivatives via copper-catalyzed dehydrogenative C O arylation has been presented. Optimization studies have been carried out by varying various catalysts, bases, solvents, and other physical parameters. Keeping use of this dehydrogenative cross-coupling C O arylation reaction, a variety of bioactive building blocks like fused benzofuro quinoline heterocycles were smoothly assembled in moderate to higher yields.     

Self-assembly of Novel Hetero[3]rotaxane,[2]Rotaxanes and [2]Catenane

One linear template 13 and one cyclophane template 15, both incorporating two electron rich 1,4-dialkoxybenzene units and one diamide unit, have been synthesized. By utilizing donor-acceptor interaction and/or intermolecular hydrogen bonding assembling principles, one novel hetero[3]rotaxane 22·4Cl, possessing one neutral and one tetracationic ring components, has been synthesized from 13, through neutral [2]rotaxane 21 as intermediate. With 15 as template, tetracationic [2]catenane 23·4PF6 was assembled by using donor-acceptor interaction, but no neutral [2]rotaxane could be obtained under the typical conditions of hydrogen bonding assembling principle. The interlocked supramolecular compounds have been characterized and their spectral properties are investigated.     

A TLC Study of the lipophilicity of thirty-two acetylcholinesterase inhibitors — 1,2,3,4-tetrahydroacridine and 2,3-dihydro-1H-cyclopenta[b]quinoline derivatives

The lipophilicity of thirty-two novel acetylcholinesterase (AChE) inhibitors — 1,2,3,4-tetrahydroacridine and 2,3-dihydro-1H-cyclopenta[b]quinoline derivatives was studied by thin layer chromatography. The analyzed compounds were chromatographed on RP-18, RP-8, RP-2, CN and NH₂ stationary phases with dioxane — citric buffer pH 3.0 binary mobile phases containing different proportions of dioxane. R_M values for pure water were extrapolated from the linear Soczewiński-Wachtmeister equation and six compounds with known literature log P values were used as reference calibration data set for computation of experimental log P values. The obtained results were compared with computationally calculated partition coefficients values (AlogPs, AClogP, AlogP, MlogP, KOWWIN, XlogP2, XlogP3) by PCA and significant differences between them were observed.