Synthesis and spectral properties of substituted 4-chlorooxazoloquinolines

Summary The treatment of a mixture of linearly and angularly annelated 2-substituted oxazolo[4,5-f]quinolones (5a–c) and oxazolo[5,4-g]quinolones (6a–c) and similarly the treatment of 2-substituted oxazolo[5,4-f]quinolones (7a–c) and oxazolo[4,5-g]quinolones (8b,c) with POCl₃ afforded substituted 4-chlorooxazolo[4,5-f]quinolines (9a–c) and 2-substituted 4-chlorooxazolo[5,4-f]quinolines (10b,c), respectively. Spectral characteristics of the synthesized derivatives (¹H and¹³C NMR, IR, UV, and MS) are discussed.Dedicated to Prof.Fritz Sauter on the occasion of his 65th birthday     

Synthesis and spectral properties of 3-furyl-4-hydroxycoumarins

3-(5-Ethoxycarbonyl-2-furyl)-4-hydroxy-6-R-7-methoxycoumarins and their 4-acyl derivatives have been synthesized. Their¹H and¹³C NMR and IR spectra, and also their absorption and fluorescence spectra, have been studied. It has been shown that some of the substances synthesized can be used as fluorescent probes in the study of membranes and of protein preparations.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 45–51, January–February, 1998.     

Studies on nitroenamines. Part III. Synthesis and spectral properties of 4-Acyl-1-arylimidazoles

The catalytic (C/Pd) hydrogenation of 3-arylamino-2-nitro-2-enones ( 1 ) in the presence of carboxylic ortho esters ( 2 ) affords 4-acyl-1-arylimidazoles ( 3 ) in yields (20–70%) which depend on the degree of substitution of the imidazole ring. The spectral properties of compounds 3 , and particularly the ¹³C-nmr spectra, reflect both the electronic and steric effects of the substituents on the π-electron delocalization and planarity of the bicyclic system.     

Synthesis and spectral properties of hexafluoroaurates

It is established that krypton difluoride (KrF₂) interacts with metallic gold in anhydrous hydrogen fluoride (HF) in the presence of alkaline and alkaline-earth metal fluorides with the formation of complex hexafluoroaurates with the general formula M^IAu^VF₆ (M^I = Li, Na, K, Rb, Cs) and bis-hexafluoroaurates M^II(Au^VF₆)₂ (M^II = Mg, Ca, Sr, Ba). As a result of the subsequent interaction of bis-hexafluoroaurates with krypton difluoride, new coordination compounds with the composition M^II(Au^VF₆)₂ · nKrF₂ (M^II = Ca, Sr, Ba; n = 0–4) were synthesized. The Raman spectra were studied and a comparative analysis of the Raman spectra of the obtained compounds was performed. The possible variants of the structural transformation of the AuF ₆ ^? anions in compounds and the position and character of the chemical bond of the “guest” (KrF₂) in these compounds are discussed.     

Synthesis and spectral properties of mixedmeso-metallocenylporphyrins

A series of mixed porphyrins with different numbers of metallocenyl (ferrocenyl and cymantrenyl) and aryl (Ph and C₆F₅) groups at themeso-positions was obtained and characterized by¹H NMR, electronic absorption, and mass spectra. The downfield shift of NH signals as well as the bathochromic shift ofQ-bands can be attributed to a distortion of the porphyrin macrocycle upon the introduction of bulkymeso-substituents. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1045–1049, May, 1998.     

Synthesis and spectral properties of fluorescent dyes based on 4-styryl-1,8-naphthalimide

The paper reports on synthesis and spectroscopic study of novel N-butyl-4-styryl-1,8-naphthalimide dyes bearing methoxy (1), dimethoxy (2), and dimethylamino (3) groups in the styryl fragment. It is shown that all synthesized compounds demonstrate positive solvatochromism, high values of Stokes shift in polar solvents, and fluorescence in the long wavelength part of visible range. These facts indicate a potential application of these compounds as fluorescent dyes in the biochemistry. The changes in the dipole moments of the molecules caused by excitation were estimated using Lippert—Mataga equation. The obtained results could be assigned to the formation of the excited states with intramolecular charge transfer. The formation of the twisted states with charge transfer was suggested in the case of compound 3, while the fluorescence quantum yield was significantly reduced in polar protic solvents.

     

Synthesis and spectral properties of novel iminophosphoranes

Three new iminophosphoranes coded as FPZ1 (Ph–C≡C–C₆H₄–N = PPh₃), FPZ2 (Ph–N = P(C₆H₄–C≡C–Ph)₃) and FPZ3 (Ph–C≡C–C₆H₄–N = P(C₆H₄–C≡C–Ph)₃) were designed and synthesized by introducing different numbers of phenylene acetylene units to FPZ0 (Ph–N = PPh₃). The effect of structural modification was studied in detail analyzing the absorption spectra, the emission spectra, and the distributions of the electron density. The absorption spectra of the new iminophosphoranes are shown to be a linear combination of the spectra of each part by the artificial combinatorial absorption spectrum, which coincides with the real one. Most probably the individual parts can’t conjugate due to the tetrahedral structure. The probably formed excimer of FPZ0 and FPZ1 causes in their solid emission spectra an obvious bathochromic shift as compared to that of FPZ2 and FPZ3. The melting point data also showed that long branches of FPZ2 and FPZ3 will attenuate the interactions between the molecules. The results of quantum chemical calculations show that the electronic density in the HOMO of FPZ1, FPZ2, and FPZ3 is delocalized over the iminoaryl moieties. The electron density in the LUMO is delocalized over the triaryl phosphine moieties, but only concentrated on two branches, which directly determines the main direction of intramolecular charge transfer.     

香豆素酰胺类化合物的合成及光谱特性

用(取代)香豆素-3-甲酰氯(Ⅰa～Ⅰc)和取代2-氨基苯并噻唑(Ⅱa～Ⅱd)作用合成了12种新的目标化合物(Ⅲa～Ⅲl),用HRMS、IR、1H NMR对化合物结构进行了表征,确定了化合物的结构,并对其紫外吸收光谱和荧光光谱进行了分析。研究发现:在紫外光谱中,新化合物(Ⅲa～Ⅲl)和原料化合物(Ⅰa～Ⅰc)相比,因共轭链的增长而使其最大吸收波长(λmax)红移;12种化合物表现出比原料化合物(Ⅰa～Ⅰc)较强的荧光性能。     

Synthesis and spectral properties of cyclopropyl-substituted phosphaalkenes

Cyclopropanecarboxylic acid chlorides5a-d react with tris(trimethylsilyl)phosphane6 in benzene at –2 °C to form cyclopropylcarbonyl-bis(trimethylsilyl)phosphanes7. These products undergo silylic rearrangement at 25 °C to yield phosphaalkenes8. Compounds 8a,b,d are formed as mixtures ofZ- andE-isomers where the latter predominate. In the case of8c, theZ-isomer is formed exclusively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 684–689, April, 1994.The authors are grateful to the Fonds der Chemischen Industrie (Germany) for financial support of this work. A. B. Kostitsyn is also grateful to the Deutscher Akademischer Austauschdienst for a grant to carry out this study. For a preliminary communicationcf. Ref. 1.     

5,15-diaminotetrabenzoporphyrins: Synthesis and spectral properties

A zinc complex of 5,15-di(N-phthalimidyl)tetrabenzoporphyrin was obtained by the reaction of Ncarboxymethylphthalimide with 1-oxo-1H-3-(1-oxoisoindolin-3-ylidenemethyl)isoindole and zinc oxide. The complex demetallation affords 5,15-di(N-phthalimidyl)tetrabenzoporphyrin. The reaction of N-phthalimidylsubstituted tetrabenzoporphyrins with hydrazine hydrate leads to the formation of 5,15-diaminotetrabenzoporphyrins. Spectral properties of these compounds were studied.     

Synthesis and spectral properties of 4-amino- and 4-acetylamino-N-arylnaphthalimides containing electron-donating groups in the N-aryl substituent

A method for the synthesis of N-aryl-substituted 4-amino- and 4-acetylaminonaphthalimide derivatives with mono- and dialkoxy groups or a 15-crown-5 moiety in the N-aryl substituent is described. The introduction of electron-donating alkoxy groups into the benzene ring of the N-aryl fragment results in fluorescence quenching of the naphthalimide chromophore, which is most pronounced in the spectra of N-acetyl derivatives. The photophysical properties of the synthesized 4-amino- and 4-acetylaminonaphthalimides depend on the solvent polarity and its specific solvating ability due to H-bonding. The crown-containing compounds are promising fluorescent chemosensors for metal cations.     

Synthesis and spectral properties of phthalimidines and phthalides

Alkaline hydrolysis of substituted 2-cyanocinnamic acids leads to the corresponding substituted 3-carboxymethylpthalimidines; acid hydrolysis of the same acids results in the formation of phthalides with an analogous structure. NMR and mass spectrometric data are examined critically.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 472–476, April, 1992.     

5,15-dialkyl-substituted tetrabenzoporphyrins and their zinc complexes. Synthesis and spectral properties

Reactions of phthalimide with capric and stearic acids gave 1-[1-(1-oxo-1H-isoindol-3-yl)nonylidene]-2,3-dihydro-1H-isoindol-3-one and 1-[1-oxo-1H-isoindol-3-yl)heptadecylidene]-2,3-dihydro-1H-isoindol-3-one, respectively. The latter were heated with zinc(II) acetate to obtain zinc complexes of 5,15-dioctyl-and 5,15-dihexadecyltetrabenzoporphyrins. The same complexes were synthesized by reaction of 1-(1-oxo-1H-isoindol-3-ylmethylidene)-2,3-dihydro-1H-isoindol-3-one with capric or stearic acid in the presence of zinc(II) oxide. The corresponding free porphyrin ligands were obtained by treatment of the metal complexes with sulfuric acid.     

Synthesis and spectral properties of novel seco-porphyrazines with eight 4-biphenyl groups

Magnesium porphyrazinate substituted with eight 4-biphenyl groups on the periphery positions has been synthesized for the first time from cyclotetramerization of 1,2-bis(4-biphenyl)maleonitrile in the presence of magnesium butanolate. Its demetalation by treatment with trifluoroacetic acid, resulted in a partially oxidized product, namely, octakis(4-biphenyl)-2-seco-porphyrazine-2,3-dione. Further reaction of this product with copper(II) acetate, zinc(II) acetate and cobalt(II) acetate has led to the metallo derivatives, [octakis(4-biphenyl)-2-seco-2,3-dioxoporphyrazinato] M(II) (M = Cu, Zn, Co). These novel compounds have been characterized by elemental analysis, together with FT-IR, ¹H NMR, UV–Vis and mass spectral data.     

Synthesis and spectral properties of europium phthalocyanine complexes

Methods for the synthesis of europium complexes with phthalocyanine and thenoyltrifluoroacetonate (tta) or ferrocenoyltrifluoroacetonate (fta) ligands are discussed. The spectral characteristics of the complexes PcEu(tta)(ttaH) and PcEu(fta)(ftaH) (Pc is phthalocyanine) are studied.     

Synthesis and spectral properties of some bis-substituted formazans

Novel, 1,4-bis-[3,3'-phenyl-5,5'-(o-carboxyphenyl)-formaz-1-yl]-benzene-o-sulphonic acid and its derivatives contained OH group at the o-, m-, p-positions of the 3-phenyl ring were synthesized. The structures of the formazans were confirmed by elemental analyses, GC-mass, IR, (1)H NMR, UV-vis spectra. Their absorption properties were investigated. It was seen that lambda(max) values shifted towards shorter wave lengths by 130nm in CSPF relative to 1,3,5-triphenylformazan (TPF) due to the fact that the structure of CSPF contained electron withdrawing COOH and SO(3)H groups (hypsochromic effect). With binding of OH group to 3-phenyl ring of CSPF, it was observed a small bathochromic effect in accordance to the electron donating effect of OH group.     

Synthesis and spectral properties of some 1,2-dithienylethenes and 1-thieny1-4-phenylbutadienes

A total of seven thiophene derivatives not previously reported have been prepared via the Knoevenagel condensation of an activated methylthiophene and a heterocyclic or aromatic aldehyde. The principal peaks in the ultraviolet and visible absorption spectra as well as some nuclear magnetic resonance data are reported for these compounds.     

Synthesis and spectral properties of long-wavelength fluorescent dyes

Benzo[a]phenoxazinium salts were synthesised by reacting 5-alkylamino-2-nitrosophenol hydrochloride with N-alkylated-naphthylamine in good to excellent yields. Photophysical properties of these fluorophores with emphasis in solvent effects were studied. Remarkable shifts in the absorption and emission maximum have been observed as a function of polarity and proton accepting capability of the solvents. The influence on the fluorescence quantum yield was also studied.     

Synthesis and spectral properties of malononitrile-based merocyanine dyes

Di-, tetra-, and hexamethine merocyanines derived from malononitrile and heterocycles with moderate (dyes 1–6), strong (7–9), and weak (10 and 11) electron-releasing ability were synthesized. The electronic structures of merocyanines 10 and 11 are similar to the neutral polyene state, whereas those of 7–9 are similar to the ideal polymethine state. These tendencies become more pronounced with increasing length of the polymethine chain. The merocyanines derived from heterocyclic residues with weak or moderate electron-releasing ability exhibit a positive solvatochromism, whereas those with strong electron-releasing ability show a negative solvatochromism. An increase in the polarity of the solvent makes the former compounds more similar to polymethines, whereas the latter become more similar to polyenes bearing opposite charges on the end groups. The nature of the factors (nonspecific solvation, specific nucleophilic and electrophilic solvation, and vibronic interactions) responsible for the observed characteristic features was analyzed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2726–2735, December, 2005.