The Сd(II) complexes with redox amphoteric 2,6-di-(tret-butyl)-4-((2-hydroxyphenyl) imino)cyclohexa-2,5-dienone ligands L1 and L2 (adducts I, II, and III) are synthesized. The structures of coordinated complexes I, II, and III are determined by X-ray diffraction (XRD) (CIF files CCDC nos. 1838319 (II) and 1838310 (III)) and confirmed by the 1Н, 13С, and 113Cd NMR spectroscopy (for complexes I and III) and IR spectroscopy data.

The reaction of 3-[(amino-2-naphthyl)amino]-5,5-dimethylcyclohex-2-en-1-one with o-quinones provided previously unknown macrolactones of the oxonine series with naphthopyrazine fragments.

Reactions of 12H-quinoxaline[2,3-b]phenoxazine (QOPO) derivatives with the CoII and ZnII hexafluoroacetylacetonates accompanied by protonation of the starting bases result in stable complexes [QOPOH]+[M(hfac)3]− whose structure was determined by X-ray diffraction and by 1H and 15N NMR spectroscopy. The complexes are characterized by long-wavelength absorption (560–664 nm) and fluorescence in the red region (λfl = 674–805 nm). The relative energies of the protonated tautomers N(14)—H and N(7)—H were determined using the results of B3LYP–D3BJ/6-311G++(d,p) density functional calculations with inclusion of D3BJ dispersion correction. A SQUID magnetometry study of the static and dynamic magnetic properties of the CoII complex revealed that it behaves as a field-induced single-ion magnet.

The synthesis of a new symmetric bis(spiropyran) of the indoline series existing as an equilibrium mixture of isomeric forms in various organic solvents is described. This equilibrium was in detail studied by dynamic NMR spectroscopy. In particular, the equilibrium constants were found at various temperatures, and the thermal effects of isomerization processes were calculated. The thermal transformations were studied by quantum chemical modeling. As a result, possible isomerization pathways were proposed and the observed ratio of the forms in the NMR spectra was explained. Photo- and thermochromic transformations were studied by UV spectroscopy, which revealed positive photochromic properties of the target compound. The observed changes in the absorption spectra with increasing temperature are completely consistent with the results of NMR studies. The nature of the absorption bands observed in the spectra was explained using time-dependent density functional theory (TD-DFT) calculations. The surface-enhanced Raman scattering (SERS) spectra of the synthesized compound on the surface of silver nanoparticles were detected and analyzed before and after UV irradiation to determine prospects for using similar bis(spiropyrans) as SERS markers and probes.

A series of new derivatives comprising heteropentacyclic 12 H -quinoxalino[2,3- b ]-phenoxazine (QOPO) system and functionalized with arylamide anchoring groups was synthesized. Their photostability as well as the spectral, luminescent, electrochemical, and optoelectronic properties were studied both in composites prepared by adsorption of QOPO onto the TiO 2 surface and in solution. Attachment of the amide anchoring groups to the QOPO core provides high adsorption of the compounds and the onset of photovoltaic properties that were not observed in the unfunctionalized precursors. However, these groups do not provide efficient injection of excited electrons into the conduction band of the semiconductor. According to B3LYP/6-311++G(d,p) density functional calculations of the model nanoclusters QOPO/(TiO 2 ) 10 , efficient electron injection and, as a consequence, high photovoltaic conversion efficiency of dye-sensitized solar cells require delocalization of the LUMO of the QOPO/TiO 2 system over both structural fragments. Relevant anchoring groups are proposed.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

2,3-Dihydro-1H-imidazo[1,2-a]benzimidazole in acetic acid, and its N-1-Me derivative in CHCl3, are brominated at position 6 with bromine. Less nucleophilic N-9-R derivatives do not enter into the reaction under these conditions, but, like their N-1-R isomers, they are quite effectively brominated by the KBrO3-HBr system, but at position 7, probably due to the transition of the reaction to the mode of bromination of protonated forms of substrates. N-1- and N-9-alkyl-6(7)-Br-2,3-dihydroimidazo[1,2-a]benzimidazoles can also be obtained by N-alkylation of 6(7)-Br-2,3-dihydroimidazo[1,2-a]benzimidazoles under neutral or basic conditions.

A condensation reaction between formyl-containing spiropyrans and iodides of 1,2,3,3-tetramethyl-3 H -indolium derivatives was studied. The reaction results in a mixture of products with a strong predominance of one of them irrespective of the structure of the starting compounds. The structures of the compounds formed during the reaction were determined based on the NMR, IR, and mass spectroscopy data. The dependence of the yield of the major reaction product on the structure of the starting compounds was studied. The prerequisites for the observed reaction pathway were established and the reaction mechanism was proposed using the results of quantum-chemical calculations based on analysis of the molecular electrostatic potential and the dual descriptor of reactivity.

1,8-Bis(dimethylamino)naphthalene (naphthalene proton sponge) equipped at position 4 with N-terminal α-amino acid residues undergoes unprecedented easy autoxidation in basic medium forming 5-dimethylamino-1,4-naphthoquinone along with minor amounts of its derivatives. The new reaction is of interest against the background of wide distribution of 1,4-naphthoquinones in nature, their high biological significance and extremely limited information on nitrogen compounds of this series.

The product of 3-formyl-2-quinolone condensation with trimethylammonium chloride acethydrazide, (H2L+)Сl– hydrazone, was synthesized. Complexes of Zn(II) and Cu(II), [M(HL)OCH3]ClO4, with a distorted square-planar strucrure of coordination sites and asymmetric chelate сomplexes of Mn(II), Ni(II), and Co(II), [M(HL)(H2L)]·(ClO4)3, of pseudo-octahedral structure were obtained on its basis. The protistocidal, antibacterial, and fungistatic activities of the synthesized compounds were studied.

The reaction of 2,3-diaminonaphthalene with dimedone gave 3-[(3-amino-2-naphthyl)amino]-5,5-dimethylcyclohex-2-en-1-one that reacts with alloxan to afford a product of addition at the enamine moiety. The latter is converted to a spiro derivative on heating in CF3COOH, or undergoes condensation with 2,6-di-tert-butyl-p-benzoquinone to give a benzophenazinone derivative with a sterically hindered phenol substituent.

The solvent-dependent selective "naked eye " chromofluorogenic multifunctional rhodamine-based probe 3 for Al3+, Cu2+, Hg2+, S2- and CN- ions was synthesized and its spectral, luminescent and ion-ochromic properties were studied. The compound obtained exists in the spirolactam form, confirmed by data of H-1, COSY, HSQC, HMBC and C-13 NMR spectroscopy. In ethanol, Al3+ ions selectively, even in the presence of other metal cations (Na+, Ba2+, Zn2+, Cd2+, Ni2+, Co2+, Cu2+, Hg2+ and Fe3+) initiate the opening of the spirolactam ring, accompanied by the appearance of a new absorption band at 556 nm and the "naked eye " effect with a change in the yellow-green color of the solution to orange-pink. At the same time, the initial fluorescence 3 at 539 nm shifts to the longer 579 nm spectral region. The use of acetone as a solvent allows the selective detection of copper(II) cations that turn the yellow color of a solution of 3 to pink-purple (lambda(abs) 563 nm) due to the formation of the ring-open complex 3.Cu2+ that exhibits emission at 580 nm. Selective detection of Hg2+ in acetonitrile results in the "naked eye " effect characterized by a change in the color of the solution from bright yellow to pink-cherry (lambda(abs) 564 nm). The fluorescence of the mercury(II) complex is observed at 587 nm. Complexes 3.Cu2+ and 3.Hg2+ were used for the sequential selective recognition of S2- and CN- anions, respectively. A combinatorial molecular logic gate was designed based on the cation/anion sensing ability of probe 3. (c) 2022 Elsevier Ltd. All rights reserved.

We report the synthesis of a new effective cobalt-based composite for catalytic reduction of water pollutant - p-nitrophenol. ZIF-67 and its Zn-substituted analog have been used as precursors for the catalyst preparation. Their pyrolysis has resulted in cobalt nanoparticles embedded into N-doped carbon substrates. We have used polyvinylidene fluoride (PVDF) as an additive to ZIF-substrates to produce mesoporous carbon shells on the surface of the catalysts. We have found that PVDF-additive enhanced the catalytic properties of the obtained composite material. Firstly, this additive reduces the total cobalt concentration in the composite by increasing carbon content. Secondly, a porous carbon shell improves the rate of catalytic reactions. According to the experimental data, PVDF additive has allowed us to obtain materials with lower Co-content but with high catalytic activity towards p-nitrophenol reduction.

A novel photochromic system based on an alkylideneisochromanedione core with heterocyclic substituents was synthesized, and its spectral luminescent and photoinduced properties were studied. The obtained iso-chromandiones containing the hexatriene fragment exist in a ring-open E-form, confirmed by the data of H-1, C-13 NMR spectroscopy and X-ray diffraction studies. The observed photoinitiated processes depend fundamentally on the nature of the heterocyclic substituents. Thiophenyl, benzo[b]thiophenyl and 1H-indolyl derivatives 5c-f are non-photochromic in the solid state, and in solutions their transformations are limited by thermally reversible E/Z-photoisomerization. Compound 5a with a furanyl substituent is photochromic in crystalline form due to the light-induced rearrangement of the ring-open hexatriene isomer into the ring-closed cyclohexadiene structure. Upon irradiation with light of 436 nm, the yellow crystals of 5a turn dark blue-green. The reverse reaction of the cycle opening and restoration of the original color of the crystals occurs extremely easily upon irradiation with visible light of 578 nm. In contrast to crystals, solutions of compounds 5a and 5b with furanyl substituents in hexane, 2-propanol, acetonitrile and DMSO are discolored when irradiated with light of 365 nm. The irreversible photorearrangement 5a,b -> 6a,b includes the stages of cyclization, the opening of the furan cycle and the formation of highly fluorescent naphthalic anhydride derivatives 6 (the quantum yield of fluorescence reaches 0.69 in hexane)), which can be used for the production of optical memory media for archive 3D discs.

β-Aminovinyl ketone (2-nitro-3-(8-quinolylamino)prop-2-enal) was synthesized by condensation of nitromalondialdehyde with 8-aminoquinoline. The reactions of β-aminovinyl ketone with copper, nickel, and cobalt acetates in methanol gave metal complexes. The spectral and magnetic characteristics of preparatively isolated compounds were studied. The structure of cobalt(II) chelate was determined on the basis of X-ray diffraction study (CIF file CCDC no. 2109263).

1-(2-Hydrazinoaryl)-3,4-dihydroisoquinolines and their hydrazinopyridyl analogues undergo recyclization affording novel (7-aza)indazolyl-β-arylethylamines. The products are expected to possess neurotropic activities.

Isonicotinic acid N′-(10-oxo-10H-phenanthren-9-ylidene)hydrazide (HL) and its complexes ML2 and MHLCl2 [М = Cu(II), Ni(II), Co(II), Fe(II), and Zn(II)] were synthesized. The structure and properties of the obtained compounds were studied by 1H NMR, IR, and X-ray absorption spectroscopy. The hydrazide structure was determined by X-ray diffraction. Quantum-chemical calculations of its tautomeric forms and electronic absorption spectra were carried out. In ML2 chelate complexes, the ligand is coordinated to metal atoms in the enol form, whereas in MHLCl2 complexes it is coordinated in the keto form.

The reaction of fluorescein-substituted 2-hydroxybenzaldehyde with 3H-indolium perchlorate has led to the formation of 1,3-dihydrospiro[indole-2,2′-chromene] bearing a fluorescein fragment at position 8 of chromene. In a solution, the obtained compound has existed in the cyclic form and has exhibited photochromic properties. Adding transition metal perchlorates to the spiropyran solution has led to intense coloration due to the complex formation. Zinc and cadmium complexes of the spiropyran have exhibited red fluorescence and negative photochromism.

A new recyclization of 3,4-dihydroisoquinolines is a convenient route to derivatives of new bbb-(o-benzothienylaryl)-and bbb-(o-thieno[2,3-b]pyridinylaryl)-containing ethylamines. These compounds look promising monoaminergic agents.