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1

Novel N,N’-bis(2,4-dimethoxybenzylidene)ethylenediamine PVC membrane electrode for the potentiometric iron selective sensor based on Schiff base ligand

Kumar Sachin, Sandhu Susheel K., Patel Agnik K., Parmar Ketankumar H.

Polimery

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2022

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Vol. 67, nr 5

197--204

EN

N,N’-bis(2,4-dimethoxybenzylidene)ethylenediamine was synthesized and used as a membrane carrier to create a novel poly(vinyl chloride) membrane potentiometric sensor that is selective especially for Fe3+ ions. The super-Nernstian slope of the projected sensor was 19.5 mV per decade over a concentration range of 7.3•10-8–1•10-1 M having detection limit at 7.3•10-8 M. The sensor displayed a linear potential response for the detection of Fe3+ ions in about 30 seconds, and it had a lifespan of no less than 9 weeks without lacking any potential divergence. The selected sensor showed high selectivity in water solutions in relation to Fe3+ ions, even in the presence of other metal cations in the pH range of 3.6–10.

PL

Przedmiotem badań był potencjometryczny czujnik do selektywnego oznaczania jonów Fe3+ oparty na membranie wykonanej z poli(chlorku winylu) i N,N’-bis(2,4-dimetoksybenzylideno)etylenodiaminy. Nachylenie super-nernstowskie (ang. super-Nernstian slop) badanego czujnika wynosiło 9,5 mV na dekadę w zakresie stężeń 7,3•10-8–1•10-1 M z limitem detekcji 7.3•10-8 M. Czujnik wykazywał w obecności jonów Fe3+ liniową odpowiedź przez około 30 s, a jego czas życia bez rozbieżności potencjałów wynosił nie mniej niż 9 tygodni. Wybrany czujnik wykazywał w roztworach wodnych wysoką selektywność w stosunku do jonów Fe3+ nawet w obecności innych kationów metali w zakresie pH 3,6–10.

2

Symmetrical and asymmetrical imino-naphthalimides in perovskite solar cells

Korzec Mateusz, Kotowicz Sonia, Pająk Agnieszka Katarzyna, Schab-Balcerzak Ewa

Opto-Electronics Review

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2021

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Vol. 29, No. 4

175--180

EN

In perovskite solar cells, series of symmetrical and asymmetrical imino-naphthalimides were tested as hole-transporting materials. The compounds exhibited high thermal stability at the temperature of the beginning of thermal decomposition above 300 °C. Obtained imino-naphthalimides were electrochemically active and their adequate energy levels confirm the application possibility in the perovskite solar cells. Imino-naphthalimides were absorbed with the maximum wavelength in the range from 331 nm to 411 nm and emitted light from the blue spectral region in a chloroform solution. The presented materials were tested in the perovskite solar cells devices with a construction of FTO/b-TiO2/m-TiO2/perovskite/ HTM/Au. For comparison, the reference perovskite cells were also performed (without hole-transporting materials layer). Of all the proposed materials tested as hole-transporting materials, the bis-(imino-naphthalimide) containing in core the triphenylamine structure showed a power conversion efficiency at 1.10% with a short-circuit current at 1.86 mA and an open-circuit voltage at 581 mV.

3

Tridentate hydrazido-hydrazones vanadium complexes. Synthesis, properties and biological activity

Szklarzewicz Janusz, Jurowska Anna, Hodorowicz Maciej, Matoga Dariusz, Gryboś Ryszard, Filipek Barbara, Sapa Jacek, Głuch-Lutwin Monika, Mordyl Barbara, Kazek Grzegorz

Science, Technology and Innovation

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2019

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Vol. 4, no. 1

9--20

EN

Nine new vanadium complexes, with tridentate Schiff base ligand based on 3,5-di-tertbutyl-2-hydroxybenzaldehyde and different hydrazides, are described and characterized. The X-ray crystal structure of complex 8 shows distorted octahedral geometry of vanadium, with ONO ligand in equatorial position. The tridentate Schiff base ligand forms six membered and five-membered chelate rings at the V(V) acceptor center, with the corresponding bite angles being 82.97(9)˚ and 74.48(9)˚. The molecules are gathered by means of intermolecular OH...N hydrogen bond and layered by π...π interactions involving the pyridine and phenolate rings. Such interactions expand the structure along the crystallographic a axis. The complexes were characterized by the elemental analyses, IR, UV-Vis, EPR spectroscopy, cyclic voltammetry, thermogravimetry and magnetic susceptibility measurements. The stabilization role of co-ligands is discussed. The cytotoxicity versus HepG2 hepatocytes and inhibition of human recombinant PTP1B was studied.

4

Thermal and long period stability of series of V(V), V(IV) and V(III) complex with Schiff base ligands in solid state

Szklarzewicz Janusz, Jurowska Anna, Hodorowicz Maciej, Gryboś Ryszard

Science, Technology and Innovation

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2019

|

Vol. 4, no. 1

30--36

EN

The synthesis and physicochemical properties of three new complexes of vanadium at +5, +4 and +3 oxidation state are described and discussed. The octahedral surrounding of vanadium for V(III) complexes of [V(L1)(HL1)] general formula is filled with two ONO tridentate ligand L, for V(IV) one ONO ligand L, oxido ligand and 1,10-phenanthroline (phen) as a co-ligand are presented in complexes of [VO(L2)(phen)]. For V(V) the complexes of [VO2(L1)(solv)] type were formed. As ligands, the H2L Schiff bases were formed in reaction between 5-hydroxysalcylaldehyde and phenylacetic hydrazide (H2L1) and 3,5- dichlorosalicyaldehyde and 4-hydroxybenzhydrazide (L2). The magnetic moment measurements, in 8 year period, show, that V(III) complexes slowly oxidise to V(IV) with preservation of the nonoxido character of the complexes, while V(IV) complexes were found to be stable. The TG and SDTA measurements indicate, that thermal stability depends mainly on the oxidation state of vanadium. The less thermally stable are the V(V) complexes, while V(IV) and V(III) are stable up to ca. 200oC. In solution, at pH 2 (similar to that in human digestion system), again the V(IV) are the most stable, only at pH 7.0 V(III) complexes had higher stability. The most stable, thus best for pharmaceutical use, are V(IV) complexes.

5

Synthesis, structure and properties of V(V) monooxido complex with ONO tridentate Schiff base

Jurowska Anna, Szklarzewicz Janusz, Hodorowicz Maciej, Gryboś Ryszard

Science, Technology and Innovation

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2019

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Vol. 4, no. 1

21--29

EN

The oxidovanadium(V) Schiff base complex of formula [VO(L)(EtO)(EtOH)] (where H2L = Schiff base ligand derived from 5-methoxysalicylaldehyde and phenylacetic hydrazide) was synthesized and described. Complex crystalizes in triclinic P-1 space group. Octahedral geometry of the vanadium(V) centre is filed with oxido, ONO L2- ligand and two solvent molecules both in ethoxo and as neutral ethanol form. The complex is neutral, with 5- and 6-memebered ring formed by ONO ligand coordinated in octahedral plane with oxido and EtOH ligands in vertical positions. Two isomers are present in the unit cell, with different position of 5-membered ring versus vertical plane. The elemental analysis, magnetic susceptibility, thermogravimetry and spectroscopy (IR, UV-Vis) measurements were measured and are discussed. The cyclic voltammetry measurements show irreversible processes for vanadium(IV/V) redox system. Thermal stability both in a solid state (TG and SDTA measurements) as well as in solutions (at pH 7.0 and 2.0, studied by UV-Vis spectroscopy) is discussed.

6

Synthesis, structure and properties of V(IV) complex with N’-[(E)-(2,3-dihydroxyphenyl)metylidene]-2- phenylacetohydrazide

Szklarzewicz Janusz, Jurowska Anna, Hodorowicz Maciej, Gryboś Ryszard

Science, Technology and Innovation

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2019

|

Vol. 4, no. 1

1--8

EN

The synthesis and physicochemical properties of new vanadium(IV) complex of formula [VO(L)(phen)] is described. The L denotes ONO tridentate Schiff base derived from 2,3-dihydroxybenzaldehyde and phenylacetic hydrazide, while phen = 1,10-phenanthroline used as a co-ligand to stabilize the V(IV) oxidation state. The single crystal X-Ray crystal structure indicates on octahedral geometry of vanadium centre, with 1,10-phenanthroline nitrogen trans to the V=O bond. The complex crystalizes in a monoclinic P21/c space group, very unusual is that only one isomer is present in the crystal structure. The structure is stabilized by very weak hydrogen bonds and H··π and π···π interactions. The phenyl ring of hydrazide is strongly curved from ONO ligand plane by 70.95˚. The spectroscopic characterization (IR, UV-Vis) as well as the cyclic voltammetry measurements are presented and discussed

7

Synthesis, structure and properties of V(III, IV and V) complexes with ONO Schiff bases

Szklarzewicz Janusz, Jurowska Anna, Olszewska Agata, Hodorowicz Maciej, Gryboś Ryszard, Kruczała Krzysztof

Science, Technology and Innovation

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2019

|

Vol. 4, no. 1

37--46

EN

The synthesis and physicochemical properties of vanadium(III,IV,V) complexes with Schiff base ligands based on 3,5-dibromo-4-methoxy-salicylaldehyde and phenylacetic hydrazide (H2L1), 5-chlorosalicylaldehyde and 4-hydroxybenzhydrazide (H2L2) and 5- chlorosalicylaldehyde and 2-hydroxybenzhydrazide (H2L3) were presented. The formulas of the complexes {[V(L1)(HL2)]·EtOH (1), [VO(L2)(phen)]·2H2O (2) and [VO(L3)(EtO)] (3)} were proposed based on the elemental analysis, IR and UV-Vis spectra. Additionally, the IR and UV-Vis spectra (in solvents as well as in a solid state) have been discussed from the vanadium oxidation state point of view. The single crystal structure of 3 shows triclinic, P-1 space group, structure is stabilized by hydrogen bonds and strong π-π stacking interactions. The oxidation state of the metal centre was also confirmed by the magnetic susceptibility measurements. The stability of the complexes was measured in pH = 7.00 and in pH = 2.00 which allows to evaluate the use of these compounds as insulin mimetic compounds.

8

Cu(II), Co(II), Ni(II), Mn(II) and Zn(II) Schiff base complexes of 3-hydroxy-4-[N-(2-hydroxynaphthylidene)-amino]-naphthalene-1-sulfonic acid: Synthesis, Spectroscopic, thermal, and antimicrobial studies

Bakare Safyah B.

Polish Journal of Chemical Technology

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2019

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Vol. 21, nr 3

26--34

EN

Five divalent transition metals Cu(II), Co(II), Ni(II), Mn(II) and Zn(II) complexes have been synthesized using 3-hydroxy-4-[N-(2-hydroxynaphthylidene)-amino]-naphthalene-1-sulfonic acid (H3L) Schiff base as a ligand derived from the condensation reaction between 4-amino-3-hydroxynaphthalene-1-sulfonic acid and 2-hydroxy-1-naphthalde-hyde. The synthesized complexes were characterized using microanalytical, conductivity, FTIR, electronic, magnetic, ESR, thermal, and SEM studies. The microanalytical values revealed that the metal-to-ligand stoichiometry is 1:1 with molecular formula [M2+(NaL)(H2O)x].nH2O (where x = 3 for all metal ions except of Zn(II) equal x = 1; n = 4, 10, 7, 4, and 6 for Cu(II), Co(II), Ni(II), Mn(II) and Zn(II), respectively). The molar conductivity result indicates that all these complexes are neutral in nature with non-electrolytic behavior. Dependently on the magnetic, electronic, and ESR spectral data, octahedral geometry is proposed for all the complexes except to zinc(II) complex is tetrahedral. Thermal assignments of the synthesized complexes indicates the coordinated and lattice water molecules are present in the complexes. SEM micrographs of the synthesized complexes have a different surface morphologies. The antimicrobial activity data show that metal complexes are more potent than the parent ligand.

9

Samorozwarstwiające się powłoki organiczne zawierające żywice epoksydowe na bazie zasad Schiffa

Waśkiewicz S., Langer E., Kuczyńska H., Kamińska-Bach G.

Farby i Lakiery

|

2018

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nr 6

5--12

PL

Żywice epoksydowe na bazie zasad Schiffa wraz z wytypowanymi żywicami akrylowymi zastosowano jako składniki spoiwa samorozwarstwiajacych się powłok organicznych. Stopień rozwarstwienia był określany za pomocą spektroskopii ATR FTIR i techniki mikroskopowej. Uzyskane wyniki rozwarstwienia powłok uzyskanych z zastosowaniem żywic epoksydowych na bazie zasad Schiffa były porównane z wynikami dla powłok sporządzonych z handlowych żywic epoksydowych na bazie bisfenolu A o porównywalnej liczbie epoksydowej. Na podstawie badań stwierdzono, że żywice epoksydowe na bazie zasad Schiffa w układzie powłokotwórczym zachowują się w podobny sposób do żywic epoksydowych na bazie bisfenolu A. Najlepsze właściwości mechaniczne i wysoki stopień rozwarstwienia uzyskano dla układu żywica epoksydowa na bazie zasady Schiffa/poli(metakrylan izobutylu). Zastosowanie samorozwarstwiajacej się kompozycji nie tylko obniżyło emisję lotnych związków organicznych (VOC) poprzez nałożenie dwóch warstw systemu powłokowego podczas jednej operacji malowania, ale jednocześnie wpłynęło na uelastycznienie kruchych żywic epoksydowych na bazie zasad Schiffa.

EN

Schiff base epoxy resin with different acrylic resins were used as a components of self-stratifying compositions. The degree of stratification was determined using the ATR FTIR spectroscopy and microscopy technique. Results were compared with those for commercial epoxy resins with a comparable epoxy number. It was concluded that Schiff base epoxy resin in a film forming composition behaves in a similar manner to BPA-based epoxy resins. The best mechanical properties and a high degree of stratification was achieved using a Schiff base epoxy resin/poly(isobutyl methacrylate) composition. Use of a self-stratifying composition not only reduces time and cost of preparing multilayer coating system, thanks to the formation of two layers in one application, but also causes the Schiff based epoxy coatings to become more flexible.

10

Zastosowanie metod dynamiki molekularnej w badaniach nad układami z wiązaniami wodorowymi

Jezierska A., Panek J. J.

Wiadomości Chemiczne

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2017

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[Z] 71, 7-8

473--495

EN

Modern computational chemistry offers a wide variety of methods allowing us to investigate very complex systems. In the current study, we would like to focus on ab initio and classical molecular dynamics to show their applications in our research. Car-Parrinello molecular dynamics (CPMD) was carried out to study compounds possessing intra- and intermolecular hydrogen bonds. Our simulations were performed in vacuum, in solvent and in crystalline phase. It is well known that intramolecular hydrogen bonding stabilizes 3D structure of molecules. The strength of the bonding and its features are influenced by inductive and steric effects. Our short overview on CPMD application to systems with intramolecular HB we start from Schiff and Mannich bases -model compounds to investigate intramolecular hydrogen bonding. Other examples reported here derive from the class of N-oxide type compounds. Special attention was devoted to another representative structure in such investigations – picolinic acid N-oxide. In some examples listed above proton transfer phenomena occurred making these compounds interesting objects for future excited state studies. Aliphatic boronic acid was used as a model example to study intermolecular hydrogen bonds based on CPMD method. Further, classical molecular dynamics was applied to investigate proteins. Here, we would like to report our results for two biomolecules. The first one is proteinase K for which the impact of mercury(II) on its catalytic center was studied. The second one is streptavidin. For the latter one its complexes with biotinylated ligands were investigated. We close our review with a paragraph describing further development and perspectives related to CPMD method.

11

Heat resisting and water-soluble chocolate polyesters containing azomethine group

Temizkan K., Kaya I.

Materials Science Poland

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2017

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Vol. 35, No. 2

303--312

EN

In this study, soluble in water poly(azomethine-ester)s (PAEs) were synthesized via elimination reactions of aromatic dihydroxy compounds containing imine bonding with terephthaloyl chloride. The structures of Schiff bases (SBs) and PAEs containing different aliphatic chains were confirmed by FT-IR, 1H-NMR, 13H-NMR C-NMR and UV-Vis analyses. Physicochemical properties of the new polymers were characterized. Thermal properties of the compounds were investigated by TGA-DTA, DMA and DSC. According to TGA measurements, the starting degradation temperatures (Ton) of P-1, P-2, P-3, and P-4 poly(azomethine-ester)s were found as 255 °C, 232 °C, 222 °C, and 221 °C, respectively. The starting degradation temperatures of the poly(azomethine-ester)s were higher than their Schiff base compounds. According to dynamical mechanical analysis (DMA) measurements, glass transition temperature (Tg) of P-1, P-2, P-3, and P-4 poly(azomethine-ester)s were found as 95 °C, 138 °C, 140 °C, and 145 °C, respectively. The morphological and topographic properties of the PAEs containing azomethine linkage in the main chain were investigated by FE-SEM and AFM, respectively. The molecular mass distributions of PAEs were determined by gel permeation chromatography (GPC). Electrochemical (E′g) and optical band gap (Eoptg ) values of the prepared SBs and PAEs were calculated from cyclic voltammetry (CV) and UV-Vis analyses. The electrochemical band gap (E′g) values of P-1, P-2, P-3 and P-4 were found as 2.44 eV, 2.41 eV, 2.39 eV and 2.39 eV, respectively, from the cyclic voltammetry.

12

Synthesis of benzthiazole derivatives grouping with substituted azetidinone ring and its functional behaviour

Kapadiy K. M., Namera D. H., Kavadia K. M., Khunt R. C.

International Letters of Chemistry, Physics and Astronomy

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2014

|

Vol. 11, iss. 3

223--232

EN

A series of Schiff derivatives (5a-q) and azetidinone by way of amide linkage analogues (6a-q) containing 2-amino benzthiazole have been synthesized. Amide linkage were adapted from acid via reaction with hydrazine hydrate followed by reaction with different substituted aldehyde derived various Arylidene derivatives comprising with various donor and acceptor functional group. The structures of the new synthesized azetidinone derivatives were characterized on the basis of 1H-NMR, Mass, IR and elemental analysis data.

13

Synthesis, characterization and antimicrobial activity of N’-benzylidene-5-bromothiophene-2-carbohydrazide derivatives

Makwana H., Naliapara Y. T.

International Letters of Chemistry, Physics and Astronomy

|

2014

|

Vol. 14, iss. 1

99--105

EN

Some new N’-benzylidene-5-bromothiophene-2-carbohydrazide derivatives possessing thiophene nucleus were synthesized and characterized by IR, NMR and mass spectral analysis. All synthesized compounds were screened for antimicrobial activity using cup plate method. All the compounds showed moderate to good antimicrobial activity and anti fungal activity.

14

Synthesis and characterization of some thiazolidinone derivatives possessing benzimidazole nucleus

Mehta P., Dawedra P., Goswami V., Joshi H. S.

International Letters of Chemistry, Physics and Astronomy

|

2014

|

Vol. 11, iss. 1

1-8

EN

Synthesis of new thiazolidinone derivatives possessing benzimidazole nucleus by condensation reaction of various substituted mercapto acids in presence of anhydrous ZnCl2. In our present study we have also synthesized Schiff bases of benzimidazole derivatives. All synthesized compounds were characterized by IR, 1H NMR and Mass spectroscopy.

15

Synthesis and characterization of some new Schiff bases of 2-oxonaphtho[2,1-b][1,4]oxazine

Chovatiya P., Mehta C., Senjani H., Shah A., Joshi H. S.

International Letters of Chemistry, Physics and Astronomy

|

2014

|

Vol. 12

26--30

EN

The literature review reveal that [1,4]-oxazine derivatives represent one of the most active classes of compounds possessing wide spectrum of biodynamic activities and use as potent therapeutic agents. In the present work, a series of Schiff base of 2-(2,3-dihydro-2-oxonaphtho[2,1-b][1,4]oxazin-1-yl)acetohydrazide, 5a-5j has been synthesized using 1-aminonaphthalen-2-ol. Various aromatic aldehyde were react with carbohydrazide 4 in the presence of acid to produce the 2-oxonaphtho[2,1-b][1,4]oxazin Schiff base derivatives with good yields. All synthesized compounds were characterized by IR, NMR and Mass spectrometry analysis.

16

Novel s-Triazinyl Schiff Base/Chalcone Congeners: Rational, Synthesis, Antimicrobial and Anti-TB Evaluation

Lakum H. P., Shah D. R., Chikhalia K. H.

International Letters of Chemistry, Physics and Astronomy

|

2014

|

Vol. 19, iss. 1

56--73

EN

The occurrence of Multi Drug Resistant (MDR) infectious microbial strains has been increased upto alarming level which affects the public health worldwide. To cure this problem, a library of s-triazinyl derivatives comprising schiff base or chalcone motif have been rationalized, synthesized and screened for their in vitro antibacterial activity against five bacterial strains (Staphylococcus aureus MTCC 96, Bacillus subtilis MTCC 441, Escherichia coli MTCC 739, Pseudomonas aeruginosa MTCC 741 and Klebsiella pneumoniae MTCC 109) and four fungal strains (Aspergillus niger MTCC 282, Aspergillus fumigates MTCC 343, Aspergillus clavatus MTCC 1323, Candida albicans MTCC 183) using broth dilution technique. All the newly synthesized scaffolds were further evaluated for their in vitro anti-TB efficacy against the tubercular strain (Mycobacterium tuberculosis H37Rv) using Lowenstein-Jensen MIC method. All the derivatives were well characterized by IR, 1H NMR, 13C NMR, elemental analysis as well as mass spectroscopy.

17

Corrosion Inhibition of Mild Steel in Nitric Acid Media by some Schiff Bases Derived from Anisalidine

Saxena N., Kumar S., Sharma M. K., Mathur S. P.

Polish Journal of Chemical Technology

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2013

|

Vol. 15, nr 1

61-67

EN

Corrosion inhibition performance of mild steel in nitric acid solution containing different concentration of anisalidine derivative Schiff bases viz. N- (4-nitro phenyl) p-anisalidine (SB1), N- (4-chloro phenyl) p-anisalidine (SB2), N- (4-phenyl) p-anisalidine (SB3), N- (4-methoxy phenyl) p-anisalidine (SB4), N- (4-hydroxy phenyl) p-anisalidine (SB5) has been investigated using mass loss, thermometric and potentiostate polarization technique. Inhibition efficiencies of Schiff bases have been evaluated at different acid strength. The inhibition efficiency was found larger than their parent amines. Inhibition efficiencies of synthesized Schiff bases increase with inhibitor concentration. Inhibition efficiency increases up to 98.32% with ansalidine derivative Schiff base.

18

Synthesis and Spectral Studies of Ru(II) Carbonyl Schiff Base Complexes

Prabhakaran B., Santhi N., Emayavaramban M.

International Letters of Chemistry, Physics and Astronomy

|

2013

|

Vol. 3

53-66

EN

The synthesis and characterization of hexa co-ordinated ruthenium(II) complexes of the type [Ru(CO)(B)(L)] (where B = PPh3, AsPh3, py or pip and L = dibasic tetradentate Schiff base ligand) were synthesized from the reaction of [RuHCl(CO)(B)(EPh3)2] (where E = P, B = PPh3, py or pip, E = As, B = AsPh3) with different tetradentate ligands. The ligands were derived by the condensation of 5-chloro-4-methyl-2-hydroxy benzophenone with ethylenediamine, propylenediamine and o-phenylene-diamine in 1:1 molar ratio. All the compounds have been characterized by elemental analysis and spectral (FT-IR, UV-VIS and 1H-NMR) methods. An octahedral environment around Ru(II) ion has been tentatively proposed for all the complexes.

19

Styrene oxidation by copper(II) complexes salen-type encapsulated into NaY zeolite

Kuźniarska-Biernacka I., Carvalho M. A., Correia Neves I., Fonseca A. M., Lisińska-Czekaj A., Czekaj D.

Archives of Metallurgy and Materials

|

2013

|

Vol. 58, iss. 4

1291--1294

EN

The copper(II) complex with a Schiff-base salen-type ligand has been encapsulated in the nanopores of a NaY zeolite by using two different methodologies, the flexible ligand and in situ complex preparation methods. The encapsulated and non-encapsulated copper(II) complexes were screened as catalysts for styrene oxidation by using TBHP as the oxygen source in acetonitrile solvent. Under the optimized conditions, the catalysts exhibited moderate activity with higher selectivity to benzaldehyde. Both heterogeneous catalysts were found to be reusable after the catalytic cycle, but with some loss of activity.

PL

Osadzenie kompleksu miedzi(II) z zasadą Schiffa typu salen na zeolicie typu NaY zostało przepowadzone za pomocą dwóch metod „flexible ligand" i „in situ”. Katalityczne właściwości otrzymanego kompleksu oraz jego heterogenizowanych analogów badano w reakcji utleniania styrenu w obecności TBHP. Jako rozpuszczalnik stosowano acetonitryl. Testowane katalizatory wykazują średnią aktywność katalityczną z tendencją wytwarzania aldehy du benzoesowego. Oba heterogenizowane katalizatory mogą być wykorzystywane ponownie bez utraty aktywności katalitycznych.

20

Synthesis, Structures, and Antibacterial Activities of 3-Methoxy-N'-(3-bromo-5-chloro-2-hydroxybenzylidene) benzohydrazide Dimethanol Solvates and 3-Hydroxy-N'-(3-bromo-5-chloro-2-hydroxybenzylidene) benzohydrazide Methanol Solvate

Zhu Q. -Y., Wei Y. -J., Wang F. -W.

Polish Journal of Chemistry

|

2009

|

Vol. 83, nr 7

1233-1240

EN

Two Schiff base com pounds, C15H12BrClN2O3×2CH3OH (1) and C14H10BrClN2O3×CH3OH (2), have been synthesized by the condensation reactions of equimolar quantities of 3-bromo-5-chlorosalicylaldehyde with 3-methoxy benzohydrazide and 3-hydroxy - benzohydrazide, respectively, in methanol solutions. Compound (1) consists of a Schiff base molecule and two metha ol molecules of crystallization, while compound (2) con - sists of a Schiff base molecule and one methanol molecule of crystallization. Both com - pounds were characterized by elemental analysis, IR spectra and single-crystal X-ray diffractions. As expected, each Schiff base molecule adopts an E-configuration about the C=N double bond. In both crystal structures, molecules are linked through intermolecular hydrogen bonds and weak Br×××O or Br×××Br interactions, forming layers. Both compounds possess potent antibacterial activities.