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1.
Single crystals of 1-isopropyl-3,3,5′,6′-tetramethylspiro[indoline-2,2′-2H-pyrano[3,2-b]-pyridinium] tris(oxalato)chromate(III) (Sp)3Cr(C2O4)3 were prepared for the first time. The molecular and crystal structure of this salt was studied by X-ray diffraction. The crystal structure of the salt consists of the structural units [3(Sp)+…Cr(C2O4)3 3−], in which the charged pyranopyridinium moieties of the photochromic cations (Sp)+ are directed toward the oxalate groups, whereas the indoline moieties are directed into the cavities between the structural units. This structure appeared to be favorable for photochromic transformations in the crystals. Under UV irradiation of the (Sp)3Cr(C2O4)3 salt, the thermally stable closed form of spiropyran (λmax = 370 nm) is transformed into the open form (λmax = 574 and 603 nm). The reverse cyclization proceeds slowly in the dark (k = 1.0(2)·10−5 s−1 and rapidly under visible light irradiation. The spectroscopic and photochromic properties of the oxalatochromate (Sp)3Cr(C2O4)3 are similar to those of the iodide SpI. The magnetic properties of (Sp)3Cr(C2O4)3 were studied before and after UV irradiation.  相似文献   

2.
2,2′-Diaryl-5,5,5′,5′-tetramethyl-3,3′-bi(pyrrol-3-ylidene)-4,4′(5H,5′H)-dione 1,1′-dioxides containing a carboxy, alkoxycarbonyl, or carbamoyl group in the para position of one or both benzene rings were synthesized. These compounds may be regarded as cyclic dinitrones with conjugated C=C bond. Mild aminolysis of carboxy groups in the title compounds may be used to introduce dinitrone fragments into oligonucleotide or polypeptide structures. Electrochemical reduction of the resulting amides involves reversible oneelectron transfer in the first step at a near-zero potential, which makes it possible to use the title compounds as electrochemically active labels in applied bioorganic electrochemistry.  相似文献   

3.
Time-resolved resonance Raman spectra of seven kinds of isotopically substituted analogues of 1′,3′,3′-trimethylspiro[2H-1-benzopyran-2,2′-indoline] in the photomerocyanine form have disclosed that only the vibrations of the cleaved benzopyran part are resonance enhanced significantly in cyclohexane and in acetonitrile solutions with 460-390 nm probe light. Dramatic changes in the resonance Raman spectra of the photomerocyanine on going from non-hydrogen-bond donor solvents to hydrogen-bond donor solvents can be interpreted as being due to changes in the relative contribution of ortho-quinoidal and zwitterionic forms in the resonance hybrid structure of the photomerocyanine: in cyclohexane and in acetonitrile the contribution of the ortho-quinoidal form is substantial, while in methanol the zwitterionic form is stabilized by hydrogen bonding with the solvent and the photomerocyanine takes an almost zwitterionic structure.  相似文献   

4.
Reaction of ethyl 6′,7′-dimethoxy-3′Н-spiro[isoquinoline-1,4′-cyclopentane]-1′-carboxylate with ammonia and isopropylamine afforded dihydroisoquinoline carboxamides that were reduced with NaBH4 in amides of 6,7-dimethoxy-4-spirocyclopentane-1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid. The reaction of unsubstituted carboxamide with chloroacetyl chloride led to chloroamide that reacted with versatile secondary amines and heterylthiols providing the corresponding substituted amino- and sulfanylamides of tetrahydroisoquinoline series.  相似文献   

5.
Russian Chemical Bulletin - A two-step procedure to synthesize (3-fluoroadamantan-1-yl)methyl isocyanate from (3-hydroxyadamantane)acetic acid that involves fluorination with Ishikawa’s...  相似文献   

6.
The mononuclear complexes (η3-terpy)M(Piv)2·MeCN (M = Fe ii (3) and Co ii (4), and Piv is the pivalate anion) were synthesized by the reactions of polymeric iron(ii) and cobalt(ii) pivalates with 2,2′:6′,2″-terpyridine (terpy). The oxidation of compound 3 affords the pentanuclear heterospin iron(ii,iii) complex (η3-terpy)Fe54-O)(μ3-OH)(μ-OH)2(μ-Piv)71-Piv)2 (5). All compounds were characterized by X-ray diffraction. Dedicated to the 90th anniversary of the L. Ya. Karpov Institute of Physical Chemistry. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1186–1190, June, 2008.  相似文献   

7.
Russian Journal of General Chemistry - 2,2′-{[(Diisopropoxyphosphoryl)methyl]azanediyl}diacetic acid has been synthesized by the Kabachnik–Fields reaction and its complexing ability...  相似文献   

8.
Computer modeling (DFT B3LYP/6-31G(d,p)/SDD) of the structure and spectral characteristics of photochromic 1,3,3,8′-tetramethyl-6′-formylspiro[indoline-2,2′-[2H]-chromene] and 1,3,3-trimethyl-6′-methoxy-8′-formyl[spiroindoline-2,2′-[2H]-chromene] complexes adsorbed onto the surface of a 10-atom silver cluster has been performed. It has been demonstrated that, depending on the position of the formyl group in the quinoline ring and the isomeric form of the spirocyclic compound, the change in the band intensity in Raman spectra caused by complexation with the silver cluster can reach three orders of magnitude.  相似文献   

9.
A novel series of Zn(II) complexes [LnZnCl2] (Ln = LA ? LF) based on N,N′,N-bis((1H-pyrazol-1-yl)methyl)amine bidentate ligands, N,N-bis((1H-pyrazol-1-yl)methyl)-3,5-dimethylaniline [LA], N,N-bis((1H-pyrazol-1-yl)methyl)-2,6-dimethylaniline [LB], N,N-bis((1H-pyrazol-1-yl)methyl)-2,6-diethylaniline [LC], N,N-bis((1H-pyrazol-1-yl)methyl)-2,6-diisopropylaniline [LD], N,N-bis((1H-pyrazol-1-yl)methyl)-4-bromoaniline [LE] and N,N-bis((1H-pyrazol-1-yl)methyl)benzhydrylamine [LF], has been synthesized and characterized. X-ray structures of these Zn(II) complexes showed a distorted tetrahedral geometry. No interaction exists between the Namine and the Zn(II) center in the [LnZnCl2] (Ln = LA ? LF) complexes, resulting in formation of an eight-membered chelate ring. [LFZnCl2] exhibited the highest catalytic activity (3.95 × 104 g PMMA/mol·Zn·h) for the polymerization of methyl methacrylate (MMA) in the presence of modified methylaluminoxane (MMAO) at 60 °C and yielded high molecular weight (Mw) (11.0 × 105 g/mol) of poly(methylmethacrylate) (PMMA). All the complexes resulted in syndiotactic enriched PMMA with high Tg (125–131 °C). The steric bulk of ligand architecture plays an influential role in controlling the catalytic activity and stereoregularity of the resultant PMMA. Further, alkyl derivatives [LnZnMe2] (Ln = LA ? LF) of synthesized Zn(II) complexes, generated in situ, showed moderate to high activities toward ring opening polymerization (ROP) of rac-lactide (rac-LA) and yielded heterotactic polylactide (PLA) with Pr up to 0.95 at ?50 °C. The activity and stereoselectivity toward ROP of rac-LA by these dimethyl Zn(II) complexes should be considered as a combined effect of steric hindrance and electronic density around the metal center.  相似文献   

10.
Methods for the synthesis of 4-amino-4′-R-3,3′-(NNO)-azoxy-1,2,5-oxadiazoles (amino-azoxyfurazans) with 4-nitro-1,2,3-triazol-1-yl and 1,2,3-triazolo[4,5-c]furazan-5-yl substituents (R) by cycloaddition of morpholinonitroethylene to 4′-amino-4-azido-3,3′-(ONN)-azoxyfurazan or oxidative condensation of 3-R-4-aminofurazans with 4-trifluoroacetylamino-3-nitrosofurazan were elaborated. Related polycyclic azo derivatives were also synthesized. For preliminary communication, see Ref. 1. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 159–163, January, 2008.  相似文献   

11.
Four homoleptic copper(II) complexes, [Cu(Meophtpy)2](ClO4)2 (Meophtpy = 4′-(4-methoxylphenyl)- 2,2′:6′,2″-terpyridine) (I), [Cu(Meophtpy)2](ClO4)2 · 2H2O (II), [Cu2(m-Clphtpy)4](ClO4)4 (m-ClPhtpy = 4′-(3-chlorophenyl)-2,2′:6′,2″-terpyridine) (III), and [Cu2(m-ClPhtpy)4](ClO4)4 (IV) have been synthesized by hydrothermal methods and characterized by IR, elemental analysis and single crystal X-ray diffraction (CIF files CCDC nos. 963375 (I), 885457 (II), 963377 (III), and 963376 (IV)). Complex II is a polymorph of I and complex IV is a polymorph of III. All these complexes are obtained with 95% ethanol solution or 50% ethanol solution and the solvent control on the crystallization are obviously found. In all complexes, the face-to-face interactions between pyridyl rings or phenyl rings facilitate the construction of 3D network in the crystal in addition to hydrogen bonds. The fluorescence properties of these complexes have been investigated.  相似文献   

12.
The crystal of the title compound (C36H29N3O,Mr = 519.62) has been prepared and structurally determined by X-ray single-crystal diffraction. It crystallizes in triclinic P ī space group with the crystal cell parameters: a = 12.544(4), b = 14.112(4), c = 17.770(5)A, α = 96.150(6), β = 106.112(5), γ = 107.156(5)°, V = 2825.7(14) ?3, Z = 4, Dc = 1.221g/cm3, μ(MoKα) = 0.074 mm-1 , F(000) = 1096,the final R = 0.0747 and wR = 0.1632 for 4713 observed reflections with I >2σ(I). The E-stereochemistry of the title compound can be confirmed by the result of the X-ray diffraction analysis.  相似文献   

13.
3,3-Dimethyl- and 3-methyl-1-(4,4-dimethyl-2,6-dioxocyclohex-1-yl)-3,4-dihydroisoquinolines have been synthesized. Crystal and molecular structures of the 3,3-dimethyl derivative have been determined. In the crystalline state this compound exists as a tautomeric form where a hydrogen atom is located at the N atom of the dihydroisoquinoline fragment of the molecule. The tautomeric equilibrium does not shift noticeably in solutions, as shown by IR, UV, and NMR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 331–336, February, 1993.  相似文献   

14.
Hexahomotrioxacalix[3]arene having [(5′-methyl-2,2′-bipyridyl)-5-yl]oxycarbonylmethoxy group with cone conformation was prepared, which shows strong Ag+ affinity and acts as a ditopic receptor for Ag+ and nBuNH3 +. A conformational change of 2,2′-bipyridyl moiety from the original outward orientation of the ring nitrogen to the inside orientation toward the thiacalixarene cavity was observed in the process of Ag+ complexation.  相似文献   

15.
A new 1-benzyl-3,3,5′,6′-tetramethylspiro[indoline-2,2′-[2H]pyrano[3,2-b]pyridinium] iodide, photochromic in the crystal state, was obtained. X-ray diffraction analysis was used for determination of crystal structures of the salt, its hydrate, and a neutral precursor. It was found that a replacement of the substituent in the indoline fragment leads to a considerable change in the crystal structure of both the neutral spiropyran and the salts as compared to the analogs studied earlier. Effects of crystal structure on photochromic properties were studied.  相似文献   

16.
17.
Acylation of 4-bromo- and 4-cyano-4-ferrocenylbiphenyl with alkanoyl chlorides afforded the corresponding 1-acyl-1-biphenylylferrocenes in 20% yields. X-ray diffraction study of the above-mentioned bromo derivative and 1-(4-cyanobiphenyl-4-yl)-1-((S)-3-methylpentanoyl)ferrocene demonstrated that these ferrocenylbiphenyl derivatives crystallize in noncentrosymmetric space groups.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1864–1870, September, 2004.  相似文献   

18.
Chalcone-like compounds 3a–l, 2-(benzylidene)-3,4-dihydronaphthalen-1(2H)-one, were synthesized from the addition of different benzaldehyde derivatives (2a–l) to 1,2,3,4-tetrahydro-1-napthalone (1) in basic medium. Mn(OAc)3-mediated addition of dimedone (4) to chalcone-like compounds gave the spirobenzofuran derivatives (5a-l), 6,6-dimethyl-3-aryl-3′,4′,6,7-tetrahydro-1′H,3H-spiro[benzofuran-2,2′-naphthalene]-1′,4 (5H)-dione, in good yields. The structures of synthesized compounds 5a–l were elucidated on basis of spectral data (NMR, IR) and elemental analysis. In addition, their antibacterial activities were screened against some human pathogenic microorganisms.  相似文献   

19.
Abstract  2-Methylbenzimidazole 1 reacted with 3-dicyanomethylidine-1-ethyl-2-oxoindoline 2 in ethyl acetate to afford 1-amino-2-cyano-3,4-dihydro-1′-ethylspiro{benzimidazo[1,2-a]pyridine-3,3′-indolin}-2′-one 6, which was used as a key intermediate in the synthesis of fused spiropolyheterocyclic derivatives of benzimidazopyridopyrimidine and/or benzimidazonaphthyridine nucleus incorporating an indoline moiety. Graphical abstract     相似文献   

20.
(4E)-6,6′,7,7′-tetrahydro-5H,5′H-4,4′-bis-1-benzothiophene and (4Z)-6,6′,7,7′-tetrahydro-5H,5′H-4,4′-bis-1-benzothiophene are studied by means of X-ray diffraction. The intermolecular interaction energy is calculated and the structural subclass of each compound is derived. These compounds have been found to have similar full crystal energies and packing efficiencies. The observed pseudosymmetry effects are described.  相似文献   

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