Expedient approach to synthesis of 4-hydroxy-2-(trifluoromethyl) quinolines through an intramolecular cyclization of ethyl 2-cyano-4,4,4-trifluoro-3 (arylamino)but-2-enoate derivatives

Molecular Diversity - Ethyl 2-cyano-4,4,4-trifluoro-3-(phenylamino)but-2-enoates have been synthesized by reaction of ethyl 2-cyanoacetate with trifluoroacetimidoyl chloride derivatives using...     

Ultrasound-assisted three-component synthesis of 3-(5-amino-1H-pyrazol-4-yl)-3-(2-hydroxy-4,4-dimethyl-6-oxocyclohex-1-enyl)indolin-2-ones in water

Indium(III) chloride was found to be an efficient catalyst for the synthesis of 3-(5-amino-1H-pyrazol-4-yl)-3-(2-hydroxy-4,4-dimethyl-6-oxocyclohex-1-enyl)indolin-2-ones by one-pot, three-component reaction of dimedone, 1H-pyrazol-5-amines and isatins in water under ultrasonic irradiation. The advantages of this method are the use of a readily available catalyst, easy workup, excellent yields, and the use of water as a solvent that is considered to be relatively environmentally benign.     

Development of practical methodologies for the synthesis of novel 3(4-oxo-4H-chromen-3-yl)acrylic acid hydrazides

We report a new environmentally-benign, convenient and facile methodology for the synthesis of new series of 3(4-oxo-4H-chromen-3-yl)acrylic acid hydrazides derivatives designed by exploring the molecular hybridization approach between isoniazide and 3(4-oxo-4H-chromen-3-yl)acrylic acids by using EDCl/HOBt under ultrasound irradiation in very short reaction time. Utilization of easy reaction conditions, isolation and purification makes this manipulation very interesting from an economic perspective.     

A novel and convenient synthesis of 4-hydroxy-6-methyl-3-(1-(phenylimino) ethyl)-2H-pyran-2-one derivatives under ultrasound irradiation

A facile, efficient and environment-friendly protocol for the synthesis of 4-hydroxy-6-methyl-3-(1-(phenylimino)ethyl)-2H-pyran-2-one derivatives has been developed by the convenient ultrasound-mediated condensation of amine with dehydroacetic acid. This method provides several advantages over current reaction methodologies including a simple work-up procedure, shorter reaction times and higher yields.     

Synthesis of new 1,5-diaryl-3-(arylamino)-1H-pyrrol-2(5H)-ones under catalyst-free and solvent-free conditions

Several new 1,5-diaryl-3-(arylamino)-1H-pyrrol-2(5H)-ones were synthesized via the three-component condensation reaction of aldehydes, aromatic amines, and ethyl pyruvate under catalyst-free and solvent-free conditions. Also, 5-(4-hydroxyl-3-nitrophenyl)-1-(4-methoxy-phenyl)-3-(4-methoxyphenylamino)-1,5-dihydro-pyrrol-2-one was synthesized using oxime instead of aldehyde. The eco-friendly, simple procedure, green procedure, catalyst-free and solvent-free conditions, short reaction times, and high yields of the products are the advantages of this method.     

Co(II) Complexes of4-((3-ethoxy-2-hydroxybenzylidene)amino)-N-(thiazol-2-yl)benzenesulphonamide and 4-((pyridin-2-ylmethylene)amino)-N-(thiazol-2-tl)benzenesulfonamide: Synthesis,Fluorescence Properties and Anticancer Activity

Two new Co(II) complexes of 4-((3-ethoxy-2-hydroxybenzylidene)amino)-N-(thiazol-2-yl)benzenesulphonamide and 4-((pyridin-2-ylmethylene)amino)-N-(thiazol-2-yl)benzene sulfonamide were synthesised. The structure of the complexes was identified by elemental analysis, FT-IR, electronic, EI mass, Powder XRD spectra and magnetic moment. The TG and DTA patterns of the complexes were supported the structures. The fluorescence quenching of these complexes with alizarin dye were premeditated and the free energy change (?G_et) for electron transfer process was designed by Rehm-Weller equation. The [Co(L₁-H)₂(H₂O)₂] and [Co(L₂)₂(H₂O)₂].2H₂O were submitted for in vitro cytotoxicity studies in human breast cancer cell line (MCF 7).     

Time-dependent density functional theory study on excited state intramolecular proton transfer of 3-hydroxy-2-(pyridin-2-yl)-4H-chromen-4-one

The time-dependent density functional theory (TDDFT) method was carried out to investigate the excited state intramolecular proton transfer (ESIPT) process of 3-hydroxy-2-(pyridin-2-yl)-4H-chromen-4-one (1a). 1a has two tautomeric forms: one is 1a(O), which is induced by intramolecular hydrogen bond O-H?O=C, and the other one is 1a(N), which is caused by intramolecular hydrogen bond O-H?N. From excited state to tautomer excited state coming from ESIPT, the hydroxyl hydrogen breaks away and the dissociated hydrogen adsorbed on pyridinic nitrogen or carbonyl oxygen formed new intramolecular HB and the corresponding bond length and bond angle varied greatly. In comparison, a similar process of proton transfer for 1a(N)H⁺ protonated 1a(N) from ground state to excited state was obtained. This detailed proton transfer mechanism was provided by molecular orbitals analysis and it may be applied to molecular switch and organic Lewis acid/base. We investigated the excited state proton transfer mechanism of the four molecules through the theoretical method for the first time and gave unambiguous geometry of excited state.     

Polyethylene glycol (PEG-400) promoted one-pot,five-component synthesis of (E)-ethyl2-(2-((E)-2-(1-(4-methyl-2-(phenylamino)thiazol-5yl)ethylidene)hydrazinyl)-4-oxothiazol-5(4H)-ylidene)acetates

Molecular Diversity - A facile, inexpensive and eco-friendly synthesis of functionalised...     

An unexpected tetracyclic product isolated during the synthesis of biscoumarins catalyzed by [MIM(CH2)4SO3H][HSO4]: Characterization and X-ray crystal structure of 7-(2-hydroxy-4-oxo-4H-chromen-3-yl)-6H,7H-chromeno[4,3-b]chromen-6-one

Under solvent-free conditions and in the presence of 3-methyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate [MIM(CH₂)₄SO₃H][HSO₄], a Brønsted acidic ionic liquid, the reaction of aromatic aldehydes with 4-hydroxycoumarin has been investigated. A wide range of aromatic aldehydes easily undergoes condensation with 4-hydroxycoumarin to afford biscoumarins with good purity in excellent yields. However, reaction of 2-hydroxybenzaldehyde with 4-hydroxycoumarin gave, not the corresponding biscoumarin, but a tetracyclic compound, 7-(2-hydroxy-4-oxo-4H-chromen-3-yl)-6H,7H-chromeno[4,3-b]chromen-6-one, in high yield.     

Convenient diastereoselective synthesis of annulated 3-substituted-(5S*,6S*,Z)-2-(2-(2,4-dinitrophenyl)hydrazono)-5,6-diphenyl-1,3-thiazinan-4-ones

Molecular Diversity - Racemic 2-(2,4-dinitrophenyl)hydrazono)-5,6-diphenyl-1,3-thiazinan-4-ones and (Z)-N′-(2,4-dinitrophenyl)-2,3-diphenylacrylohydrazide were formed during the...     

2-(1,2,4-三唑-1-基)-2-(3'',4''-二苯基-噻唑-2''-烯基)苯乙酮的波谱分析

本文合成了2－（1，2，4－三唑－1－基）－2－（3’，4’－二苯基－噻唑－2’－烯基）苯乙酮，对其进行了元素分析,并研究了该化合物的IR、^1HNMR及MS等波谱性质，从而确定了其结构。     

Electron spectra of 4-substituted 1,2,4-triazine-3(2H)-thion(one)-5(4H)-ones

Substitution reactions in 1,2,4-triazine-3,5-thiones are studied. Their interaction with sodium nitrite in a hydrochloric acid medium and with N,N-dimethylcarbamoylbromide yields the 4-nitroso, azo, and carbamoyl derivatives of 1,2,4-triazines. The assignment of absorption bands in electron spectra of the compounds is discussed. Sumy State University, 2, Korsakov St., Sumy, 244007, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 112–115, January–February, 1997.     

Spectral behavior study of 3-(4-dimethylamino-phenyl)-1-{6-[3-(4-dimethylamino-phenyl)-acryloyl]-pyridin-2-yl}-propanone

The photophysical properties such as singlet absorption, molar absorptivity, fluorescence spectra, fluorescence quantum yield (?_f) and transition dipole moment (μ₁₂) of 3-(4-dimethylamino-phenyl)-1-{6-[3-(4-dimethylamino-phenyl)-acryloyl]-pyridin-2-yl}-propanone (DMAPAPP) have been studied in different media. DMAPAPP exhibits a large red-shift in both absorption and emission spectra as the solvent polarity increases, indicating a large change in dipole moment of molecule upon excitation. The fluorescence quantum yield depends on the nature of the solvent. The absorption and emission spectra of DMAPAPP in dioxane–water mixture are also studied. The effect of different type of surfactants to determine their critical micellar concentration (CMC) and the microemulsion effect on the electronic absorption and emission spectra of DMAPAPP are recorded. The effect of acidity on the electronic absorption and emission spectra of DMAPAPP is studied to determine the pK_a and pK_a^? values.     

Organic synthesis in water: a green protocol for the synthesis of 2-(cyclohexylamino)-3- aryl- indeno[1,2-b]furan-4-ones

Aldehydes, 1,3-indandione and cyclohexylisocyanide undergo smooth coupling-cyclization in water to produce the corresponding 2-(cyclohexylamino)-3-aryl- indeno [1,2-b] furan-4-ones in good yields. Water was used as a solvent to avoid the use of other highly toxic and environmentally unfavorable solvents for this synthesis.

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Graphical Abstract  A simple and efficient synthesis of 2-(cyclohexylamino)-3-aryl- indeno[1,2-b]furan-4-ones was achieved via a one-pot three-component reaction of cyclohexylisocyanide, aldehydes, and 1,3-indandione in water for 5 h in good yields. zFX

     

1，1-二（苯并咪唑-2-基）-2-（N-乙基咔唑-3-基）乙烯的合成及其性能研究

以六氢吡啶为催化剂,通过Vilsmerier-Haack和Knoevenagel反应合成了一种新型的芳稠杂环化合物1,1-二（苯并咪唑-2-基）-2-（N-乙基咔唑-3-基）乙烯,产率为72.53%。利用元素分析、FT-IR、UV-Vis、¹H NMR、溶液和固体荧光光谱、循环伏安（CV）分析、TG-DTA热分析研究了产物的结构、光学特性、电化学特性和热稳定性。该化合物在DMF、DMSO和DCM 3种溶剂的稀溶液中均具有290 nm和375 nm两处紫外吸收峰以及470 nm处的蓝绿色荧光发射。不同DMSO和DCM体积比的混合溶剂的溶液荧光表明,该化合物具有明显的AIE荧光效应。固体荧光光谱表明,产物在327 nm和436 nm有两处激发峰,最大发射峰位于484 nm,相 比于溶液荧光发生了红移现象。由循环伏安测试结果计算获得产物的能隙为2.79 eV,电离势为5.43 eV,电子亲和势为2.85 eV,表明产物具有良好的电子传输能力。TG/DTA测试结果显示目标产物具有良好的热稳定性。     

Crystal structure of ethyl (2Z)-2-(3-methoxy-4-acetyloxy benzylidene)-7-methyl-3-oxo-5-phenyl-2,3-dihydro-5H-[1,3]thiazolo[3,2-a]pyrimidine-6-carboxylate

The title compound, C₂₆H₂₄N₂O₆S, (I), crystallizes in the monoclinic space group, P2₁/c, with cell parameters a = 16.248(1), b = 7.927(1), c = 19.371(4) ?, β = 105.295(2)°, Z = 4. The central pyrimidine ring in the compound (I) is significantly puckered, assuming a screw-boat conformation. The C11–C16 benzene ring stands vertical while thiazole and C18–C23 benzene rings are coplanar to the mean plane of pyrimidine ring having dihedral angles of 87.48(12), 3.63(11) and 0.94(12)°, respectively. In the absence of potential hydrogen bonding interaction, the crystal packing is influenced by intramolecular C-H…S interaction and intermolecular C-H…π interactions.     

An efficient solvent-free synthesis of 2-(alkylamino)-2-oxo-1-arylethyl-6,12-dioxo-6,12-dihydroindolo[1,2-b]isoquinoline-11-carboxylate derivatives via four-component reaction

Molecular Diversity - A one-pot approach for the synthesis of a new series of 2-(alkylamino)-2-oxo-1-arylethyl-6,12-dioxo-6,12-dihydroindolo[1,2-b]isoquinoline-11-carboxylate derivatives via a...