Next Article in Journal
Editorial: Special Issue on “Catalytic Processes in Biofuel Production and Biomass Valorization”
Previous Article in Journal
Electrocatalytic Oxygen Reduction Reaction by the Pd/Fe-N-C Catalyst and Application in a Zn–Air Battery
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Catalysts
Volume 12
Issue 12
10.3390/catal12121642
catalysts-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Aerial Oxidation of Phenol/Catechol in the Presence of Catalytic Amounts of [(Cl)2Mn(RCOOET)], RCOOET= Ethyl-5-Methyl-1-(((6-Methyl-3-Nitropyridin-2-yl)Amino)Methyl)-1H-Pyrazole-3-Carboxylate

by
Mohamed El Boutaybi
1,*,
Abderrahim Titi
2,
Abdullah Y. A. Alzahrani
3,
Zahra Bahari
1,
Monique Tillard
4,
Belkheir Hammouti
2 and
Rachid Touzani
2,*
1
Laboratory of Molecular Chemistry Materials and Environment (LMCME), Multidisciplinary Faculty of Nador, University Mohammed Premier, Oujda 60000, Morocco
2
Laboratory of Environment and Applied Chemistry (LEAC), Faculty of Sciences, University Mohammed Premier, Oujda 60000, Morocco
3
Department of Chemistry, Faculty of Science and Arts, King Khalid University, Mohail Assir 62529, Saudi Arabia
4
ICGM, University of Montpellier, CNRS, ENSCM, 34095 Montpellier, France
*
Authors to whom correspondence should be addressed.
Catalysts 2022, 12(12), 1642; https://doi.org/10.3390/catal12121642
Submission received: 2 November 2022 / Revised: 3 December 2022 / Accepted: 10 December 2022 / Published: 14 December 2022
Browse Figures
Versions Notes

Abstract

:
In this work, we report on the catalytic activity of a manganese complex [(Cl)2Mn(RCOOET)], where RCOOET is ethyl-5-methyl-1-(((6-methyl-3-nitropyridin-2-yl)amino)methyl)-1H-pyrazole-3-carboxylate, in the oxidation of phenol or catechol by atmospheric oxygen to form o-quinone. The [(Cl)2Mn(RCOOET)] catalyzes the oxidation of catechol at a rate of 3.74 µmol L−1 min−1 in tetrahydrofuran (THF), in a similar manner to catecholase or tyrosinase.

1. Introduction

Oxidation is one of the fundamental reactions of organic synthesis. In the bulk chemical industries, molecular oxygen is used as the primary oxidant owing to its economic considerations and environmental compatibility [1,2,3,4,5]. Efficient oxygen transport and aerobic metabolism are very crucial in most living organisms, and these are accomplished by iron or copper-containing metalloproteins [6]. The copper-containing metalloproteins have homeostatic functions such as providing defense (as antioxidants) against reactive oxygen species and pigment formation. The copper-containing metalloproteins can be divided into three groups, which contain different kinds of active sites based on their spectroscopic characteristics [7,8,9,10,11]: type 1 (blue), type 2 (normal), and type 3 (binuclear). The type 2 and 3 copper active sites form a trinuclear cluster, which is found in all structurally known multicopper oxidases, and this cluster is the site for oxygen binding and oxidation [12,13].
In the present study, two enzymatic oxidative transformations are discussed, i.e., those catalyzed by catecholase or tyrosinase. Catecholase is a lesser-known member of the type 3 copper-containing metalloproteins [14]. Using molecular oxygen, catecholase catalyzes the oxidation of a wide range of o-diphenols to their respective o-quinones, for which two electrons are transferred [15]. The catalytic activity of catecholase has been extensively investigated by modeling the active sites and incorporating various metals, namely copper [16,17,18,19,20,21,22,23,24,25,26,27,28,29], iron [30,31,32,33], cobalt [34,35,36,37,38], manganese [39,40,41,42,43,44,45,46,47,48,49,50], and zinc [51]. Mn(II) better catalyzes the oxidation reaction of phenol to o-quinone, that is why our work focuses on this kind of metal. Tyrosinase catalyzes two different reactions [52,53], namely the hydroxylation of monophenols to dihydroxyphenylalanine and the oxidation of o-diphenols to o-quinones.
This study discusses the development of a new catechol oxidase metalloenzyme, mimetic complex [(Cl)2Mn(RCOOET), for the catalytic oxidation of catechol or phenol to o-quinones. The manganese(II) complex catalyzed the catechol’s oxidation, and its catalytic activity increased with the reaction time with a rate of 3.74 μmol L−1 min−1 in THF.

2. Results and Discussion

2.1. Crystal Structure of C14H17N5O4 (RCOOET)

The triclinic P 1 ¯ unit cell of C14H17N5O4 contains two molecules symmetry-related by the inversion center. The main crystalline characteristics and refinement data are reported in Table 1. The full results are available in a CIF file by giving the CCDC number 2178103 at the Cambridge Crystallographic Data Center [54].
The structure of the RCOOET complementary moieties of the molecules of the ligand are arranged in two planes which are at an angle of about 66.8° (Figure 1). The first plane contains N3 and the methyl nitropyridinyl atoms, while the second contains the rest of the molecule. The deviation of atoms from their mean plane does not exceed 0.004 Å. The packing of the molecules in the crystal is stabilized by hydrogen-type intermolecular bonding. The current structural data brings an improvement to the previous structural report [55].

2.2. IR Analysis

Figure 2 exhibits the important spectral bands of the ligand and its metal complex. The IR spectra of both the ligand and the complex show a band in the zone of 3365 cm−1, which corresponds to the N–H band. Other bands at 1711 cm−1, 1644 cm−1, and 1583 cm−1 are assigned to the C=O, C=N and C=C vibrations, respectively. The strong and sharp vibrational peak at 1491 cm−1 is due to C–NO2, while in the Mn complex, C–O and C–N bands are localized at 1249 cm−1 and 1100 cm−1, respectively. Moreover, the presence of a weak broad band at 542 cm−1 in the IR spectrum of the complex suggests the coordination of the ligand to the Mn(II) ion.

2.3. Thermal Analysis

TGA and DTA were performed to monitor the thermal stability of the ligand and its Mn complex. The temperature was increased from room temperature to 950 °C, at a rate of 10 °C/min under a nitrogen atmosphere. The resulting TGA and DTA thermal curves for the manganese complex are shown in Figure 3.
The mass losses and the respective gaseous (volatile) product obtained from the TGA curves are collected in Table 2 with the species proposed as mass loss. As can be seen in the table, at higher temperatures the complex undergoes further decomposition in several stages, with the loss of one or more fragments.

2.4. Catecholase Mimicking Activity of [(Cl)2Mn(RCOOET)]

The catecholase-mimicking activity of [(Cl)2Mn(RCOOET)] towards catechol oxidation in aerated THF (saturated with molecular oxygen) was investigated spectrophotometrically by following the absorption of the corresponding o-quinone at 390 nm over time. The evolution of the absorption of o-quinone in the presence of the complex prepared in situ in THF and the synthesized complex in THF is shown schematically in Figure 4.
Figure 5 shows the UV-visible spectrum of the absorption of o-quinone in the presence of the synthesized complex in THF. It is clear that no peak occurs when catechol is used alone, and that the intensity of the absorption peak of o-quinone at 390 nm increases due to the presence of the synthesized complex in the catechol solution. The evolution of o-quinone absorption was followed up for 3 h, and the spectra were recorded every 30 min.
In both cases, it was observed that the absorbance of o-quinone increased with time, indicating that [(Cl)2Mn(RCOOET)] catalyzed the aerial oxidation of catechol to o-quinone over time. To understand the effect of the solvent, similar experiments were run under the same thermodynamic conditions with MeOH as the solvent. Again, the aerial oxidation of catechol in the presence of the Mn(II) complex was evidenced by the evolution of the absorption of o-quinone in the presence of the synthesized complex in MeOH or the in situ prepared complex in MeOH, and this is shown schematically in Figure 4. The calculated catechol oxidation rates are reported in Table 3. It is observed that the rate of oxidation of catechol in THF is higher (ν = 3.74 µmol L−1 min−1). It can be speculated that THF showed excellent catalytic activity for the oxidation of catechol to o-quinone. Polar solvents such as THF can strongly solvate Cl− anions by creating hydrogen bonds. Furthermore, THF is a good σ donor and poor π acceptor.

2.5. Kinetic Study

The mechanism and the rate of the oxidation of catechol to o-quinone by dioxygen, and catalyzation by [(Cl)2Mn(RCOOET)], were studied by the method of initial rates. For the procedure, 0.3 mL of the complex solution (2 × 10−3 mol L−1) and 2 mL of the catechol solution (concentration varied from 10−3 mol L−1 to 3 × 10−1 mol L−1) were mixed together, and the absorbance of o-quinone at 390 nm was noted every 5 min. As shown in Figure 6, a plot of the initial rate, V, versus [Catechol] shows saturation kinetics. To test the enzymolysis kinetics, the Michaelis–Menten model was applied. A plot of the reciprocals of rate and [catechol] is shown in Figure 7. It is almost linear only in the concentration range 10−3 M–3 × 10−1 M. The linear fit gave the kinetic parameters shown in Table 4 for the catechol oxidation in the presence of catalytic amounts of [(Cl)2Mn(RCOOET)]. The smaller Km is, the more maximal enzyme activity is reached for a low level of substrate concentration. The affinity of the enzyme for the substrate is high.

2.6. Tyrosinase Mimicking Activity of [(Cl)2Mn(RCOOET)]

To study the tyrosinase-mimicking activity of [(Cl)2Mn(RCOOET)] towards the aerial oxidation of phenol, a kinetic method analogous to that described for the catecholase-mimicking activity was used, using phenol as a substrate. The evolution of the absorption of o-quinone due to the oxidation of phenol by oxygen in MeOH in the presence of the [(Cl)2Mn(RCOOET)], which had been formed in situ in MeOH or pre-synthesized, is shown schematically in Figure 8. The spectral changes indicated that the complex catalyzes the oxidation of phenol.
Figure 9 shows the UV-visible overlay spectra of the absorption of o-quinone in the presence of the synthesized [(Cl)2Mn(RCOOET)] in MeOH. A peak appears at 390 nm after the addition of the complex solution to the phenol solution, and the absorbance of o-quinone increases over time. The evolution of o-quinone absorption was followed up for 2 h 30 min, and the spectra were recorded every 15 min.

2.7. Proposed Mechanism of Action of Catechol Oxidase

Different approaches have been used by different research groups to study the mechanism of complexes with catecholase-like activity. In this work, we propose that the dioxygen is reduced by catechol to hydrogen peroxide (Scheme 1). Similar to the catalyzed oxidation of catechol by catecholase, the substrate is primarily coordinated to the [(Cl)2Mn(RCOOET)] complex monodentately, and this is followed by its rapid oxidation to o-quinone and the concurrent reduction of Mn(II) to Mn(I).

3. Materials and Methods

3.1. Materials

The chemicals and solvents, 6-methyl-3-nitropyridinamine (97%), methanol, acetonitrile, tetrahydrofuran, diethyl ether, dihydroxy-1,2-benzene (catechol), phenol, magnesium sulfate, dichloromethane, as well as the metal salt (MnCl2,4H2O) were purchased from Sigma-Aldrich and used without any further purification. 1H NMR and 13C NMR spectra were recorded on a Bruker Advance Digital 400 NMR spectrometer. Chemical shifts were recorded in parts per million (ppm) using SiMe4 (TMS) as an internal standard. The elemental analysis was conducted using a 2400 Series II CHNS/O Elemental Analyzer.

3.2. Methods

3.2.1. Synthesis of Ethyl-5-Methyl-1-(((6-Methyl-3-Nitropyridin-2-yl)Amino)Methyl)-1H-Pyrazole Carboxylate (RCOOET)

The ligand (RCOOET) was prepared by using a procedure described in the literature [56]. The solution of ethyl 1-(hydroxymethyl)-5-methyl-1H-pyrazole-3-carboxylate in CH2Cl2 (1 eq.) was added to the solution of 6-methyl-3-nitropyridin-2-amine in CH2Cl2 (1 eq.) (Scheme 2). The mixture was stirred at room temperature for 4 days and then dried over MgSO4. The product was recrystallized from the resultant solution using a mixture of methanol with a few drops of ether. After 3 days, the obtained yellow product was filtered and washed with methanol (2 × 50 mL), followed by washing with Et2O (2 × 50 mL) to yield the ligand RCOOET as the final product. The structure of RCOOET is shown in Scheme 2.
Yellow product (1.5 g, 52.3% yield). mp = 454 K. FT-IR, cm−1: 1100 (C-N), 1249 (C-O), 1491 (C-NO2), 1583 (C=C), 1644 (C=N), 1711 (C=O), 3365 (N-H). UV-vis (λ = 335 nm, 347 nm, and 368 nm). 1H NMR (400 MHz, CDCl3): δH = 1.40 (t, 3H, CH3), 2.54 (s, 3H, CH3Pyr), 2.57 (s, 3H, CH3Ar), 4.4 (q, 2H, CH2), 5.99 (d, 2H, CH2), 6.55 (s, 1H, CPyr), 6.65 (d, 1H, CHAr), 8.33 (d, CH, CHAr), and 8.98 (t, 1H, NH). 13C NMR (100 MHz, CDCl3): δC = 11.35 (CH3), 14.42 (CH3), 24.95 (CH3), 53.73 (CH2), 60.99 (CH2), 108.27 (CHPyr), 113.93 (CHAr), 126.53 (CHAr), 135.68 (CPyr), 140.64 (CAr), 143.73 (CAr), 150.25 (CAr), 162.42 (CAr), and 165.59 (Cest). Elemental Analysis: C, 52.66%; H, 5.37%; N, 21.93% (calculated); C, 52.73%; H, 5.31%; N, 22.01% (found).

3.2.2. X-ray Single Crystal Study of RCOOET

Yellow stick-shaped crystals of the free ligand were selected for the singularity using a stereo microscope with a polarizing filter. The measurement of diffracted intensities was performed at ambient temperature on a 4-circle diffractometer, a Bruker D8 Venture device, using a Mo micro-source (Incoatec IµS 3.0, 110 µm beam, Kα radiation) and a Photon II CPAD detector. Reflections (27,294, up to θmax of 27.04°) were handled in the Apex software suite [57] and indexed in a triclinic lattice, a = 6.8641(3), b = 11.2751(6), c = 11.6535(6) Å, α = 112.886(2), β = 104.104(2), γ = 99.536(2)°. The SHELX programs were used for the structure solution and full-matrix least-square refinements [58]. Non-H atoms were considered with anisotropic displacement parameters.

3.2.3. Synthesis of [(Cl)2Mn(RCOOET)]

The solution of 1 equivalent of MnCl2.4H2O (123.95 mg, 0.626 mmol) in 5 mL of methanol was added to a solution of 1 equivalent of RCOOET (200 mg, 0.626 mmol) in 10 mL of acetonitrile. A yellow-colored solution was filtered to remove the solid impurities. Then, the filtrate was allowed to evaporate at room temperature for more than one week to obtain a yellow powder of [(Cl)2Mn(RCOOET)]. The structure of the expected [(Cl)2Mn(RCOOET)] is shown in Scheme 3.

3.2.4. Catecholase and Tyrosinase Activity of [(Cl)2Mn(RCOOET)]

The biochemical oxidation of phenol and catechol by molecular oxygen to form o-quinone is catalyzed by tyrosinase and catecholase, respectively. The general catalytic cycle is shown in Scheme 4. The synthesized complex, [(Cl)2Mn(RCOOET)], has the potential to mimic these two enzymes for the catalytic oxidation of phenols by dioxygen to form their respective quinones. To study the catecholase- and tyrosinase-mimetic activity of [(Cl)2Mn(RCOOET)], catechol or phenol was reacted with O2 (from the aerated solvent), in the presence of catalytic amounts of the complex. The catalytic-mimetic activity and, hence, the progress of the reactions were monitored spectrophotometrically in THF or methanol under ambient conditions. Two sets of experiments were carried out. In the first set, initially, 0.15 mL of MnCl2.4H2O (2 mmol) and 0.15 mL of RCOOET solution (2 mmol) were mixed in a spectrophotometric cell to prepare the complex in situ, followed by the addition of 2 mL of the substrate. In the second set, 0.3 mL of the previously prepared complex solution (10−1 mol.L−1) was mixed with 2 mL of the substrate. The evolution of the absorption of o-quinone over time (from 0 to 65 min) was noted for both sets at 390 nm using UV-Vis spectroscopy.

4. Conclusions

A pyrazole-based ligand, ethyl-5-methyl-1-(((6-methyl-3-nitropyridin-2-yl)amino)methyl)-1H-pyrazole-3-carboxylate, and its complex were successfully synthesized. These compounds were analyzed using different characterization techniques, such as FTIR, DRX, and ATG-ATD, and later dual activity, mimicking the catecholase activity towards the oxidation of the catechol to o-quinone, and mimicking the tyrosinase activity towards the oxidation of phenol to catechol and then to o-quinone. The pre-synthesized [(Cl)2Mn(RCOOET)] complex showed a higher oxidation rate in THF (3.74 μmol.L−1.min−1) than in MeOH (0.16 μmol.L−1.min−1) for the oxidation of catechol to o-quinone, indicating that the type of solvent plays an important role in the catalytic activity of the complex.

Author Contributions

Conceptualization, R.T. and M.E.B.; methodology, M.E.B. and A.T. software, M.T.; validation, B.H. and A.T.; formal analysis, R.T. and M.E.B.; investigation, R.T.; resources, Z.B.; data curation, A.T. and M.E.B.; writing—original draft preparation, A.T. and M.E.B.; writing—review and editing, A.Y.A.A. and M.T.; supervision, R.T. and Z.B.; project administration, A.Y.A.A.; funding acquisition, A.Y.A.A. All authors have read and agreed to the published version of the manuscript.

Funding

The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work through the Large Research Project under grant number (RGP.2/191/43).

Data Availability Statement

Data available upon request from corresponding authors.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Gligorich, K.M.; Sigman, M.S. Recent advancements and challenges of palladium II-catalyzed oxidation reactions with molecular oxygen as the sole oxidant. Chem. Commun. 2009, 3854–3867. [Google Scholar] [CrossRef] [PubMed]
  2. Piera, J.; Backvall, J.E. Catalytic oxidation of organic substrates by molecular oxygen and hydrogen peroxide by multistep electron transfer—A biomimetic approach. Angew. Chem. Int. Ed. 2008, 47, 3506–3523. [Google Scholar] [CrossRef] [PubMed]
  3. Stahl, S.S. Palladium-Catalyzed Oxidation of Organic Chemicals with O2. Science 2005, 309, 1824–1826. [Google Scholar] [CrossRef] [PubMed]
  4. Punniyamurthy, T.; Velusamy, S.J. Recent advances in transition metal catalyzed oxidation of organic substrates with molecular oxygen. Iqbal Chem. Rev. 2005, 105, 2329–2363. [Google Scholar] [CrossRef] [PubMed]
  5. Stahl, S.S. Palladium oxidase catalysis: Selective oxidation of organic chemicals by direct dioxygen-coupled turnover. Angew. Chem. Int. Ed. 2004, 43, 3400–3420. [Google Scholar] [CrossRef] [PubMed]
  6. Gerdemann, C.; Eicken, C.; Krebs, B. The crystal structure of catechol oxidase: New insight into the function of type-3 copper proteins. Acc. Chem. Res. 2002, 35, 183–191. [Google Scholar] [CrossRef]
  7. Palm-Espling, M.E.; Niemiec, M.S.; Wittung-Stafshede, P. Role of metal in folding and stability of copper proteins in vitro. Biochim. Biophys. Acta-Mol. Cell Res. 2012, 1823, 1594–1603. [Google Scholar] [CrossRef] [Green Version]
  8. Huffman, D.L.; O’Halloran, T.V. Function, structure, and mechanism of intracellular copper trafficking proteins. Annu. Rev. Biochem. 2001, 70, 677–701. [Google Scholar] [CrossRef]
  9. Puig, S.; Thiele, D.J. Molecular mechanisms of copper uptake and distribution. Curr. Opin. Chem. Biol. 2002, 6, 171–180. [Google Scholar] [CrossRef]
  10. Harris, E.D. Basic and clinical aspects of copper. Crit. Rev. Clin. Lab. Sci. 2003, 40, 547–586. [Google Scholar] [CrossRef]
  11. Malmström, B.G. Enzymology of oxygen. Annu. Rev. Biochem. 1982, 51, 21–59. [Google Scholar] [CrossRef]
  12. Messerschmidt, A.; Rossi, A.; Ladenstein, R.; Huber, R.; Bolognesi, M.; Gatti, G.; Marchesini, A.; Petruzzelli, R.; Finazziagro, A.J. X-ray crystal structure of the blue oxidase ascorbate oxidase from zucchini: Analysis of the polypeptide fold and a model of the copper sites and ligands. Mol. Biol. 1989, 206, 513–529. [Google Scholar] [CrossRef]
  13. Spira-Solomon, D.J.; Allendorf, M.D.; Solomon, E.I. Low-temperature magnetic circular dichroism studies of native laccase: Confirmation of a trinuclear copper active site. J. Am. Chem. Soc. 1986, 108, 5318–5328. [Google Scholar] [CrossRef]
  14. Solomon, E.I.; Sundaram, U.M.; Machonkin, T.E. Multicopper oxidases and oxygenases. Chem. Rev. 1996, 96, 2563–2605. [Google Scholar] [CrossRef]
  15. Gerdemann, C.; Eicken, C.; Galla, H.-J.; Krebs, B.J. Comparative modeling of the latent form of a plant catechol oxidase using a molluskan hemocyanin structure. Inorg. Biochem. 2002, 89, 155–158. [Google Scholar] [CrossRef] [PubMed]
  16. Patra, A.; Giri, G.C.; Sen, T.K.; Carrella, L.; Mandal, S.K.; Bera, M. Bis (μ-alkoxo) bridged dinuclear CuII2 and ZnII2 complexes of an isoindol functionality based new ligand: Synthesis, structure, spectral characterization, magnetic properties and catechol oxidase activity. Polyhedron 2014, 67, 495–504. [Google Scholar] [CrossRef]
  17. Mandal, S.; Mukherjee, J.; Lloret, F.; Mukherjee, F. Modeling Tyrosinase and Catecholase Activity Using New m-Xylyl-Based Ligands with Bidentate Alkylamine Terminal Coordination. Inorg. Chem. 2012, 51, 13148–13161. [Google Scholar] [CrossRef]
  18. Biswas, A.; Das, L.K.; Drew, M.G.B.; Diaz, C.; Ghosh, A. Insertion of a hydroxido bridge into a diphenoxido dinuclear copper (II) complex: Drastic change of the magnetic property from strong antiferromagnetic to ferromagnetic and enhancement in the catecholase activity. Inorg. Chem. 2012, 51, 10111–10121. [Google Scholar] [CrossRef]
  19. Agotegaray, M.A.; Dennehy, M.; Boeris, M.A.; Grela, M.A.; Burrow, R.A.; Quin-zani, O.V. Therapeutic properties, SOD and catecholase mimetic activities of novel ternary copper (II) complexes of the anti-inflammatory drug Fenoprofen with imidazole and caffeine. Polyhedron 2012, 34, 74–83. [Google Scholar] [CrossRef]
  20. Sadhukhan, D.; Ray, A.; Butcher, R.J.; Gomez Garcia, C.J.; Dede, B.; Mitra, S. Magnetic and catalytic properties of a new copper (II)–Schiff base 2D coordination polymer formed by connected helical chains. Inorg. Chim. Acta 2011, 376, 245–254. [Google Scholar] [CrossRef]
  21. Panda, M.K.; Shaikh, M.M.; Butcher, R.J.; Ghosh, P. Functional mimics of catechol oxidase by mononuclear copper complexes of sterically demanding [NNO] ligands. Inorg. Chim. Acta 2011, 372, 145–151. [Google Scholar] [CrossRef]
  22. Majumder, S.; Sarkar, S.; Sasmal, S.; Sanudo, E.C.; Mohanta, S. Heterobridged dinuclear, tetranuclear, dinuclear-based 1-D, and heptanuclear-based 1-D complexes of copper (II) derived from a dinucleating ligand: Syntheses, structures, magnetochemistry, spectroscopy, and catecholase activity. Inorg. Chem. 2011, 50, 7540–7554. [Google Scholar] [CrossRef] [PubMed]
  23. Bakshi, R.; Rossi, M.; Caruso, F.; Mathur, P. Copper (II) complexes of a new N-picolylated bis benzimidazolyl diamide ligand: Synthesis, crystal structure and catechol oxidase studies. Inorg. Chim. Acta 2011, 376, 175–188. [Google Scholar] [CrossRef]
  24. El Boutaybi, M.; Bouroumane, N.; Azzouzi, M.; Bacroume, S.; Touzani, R.; Bahari, Z. Catecholase, phenoxazinone synthase and copper (CuII) complex based on pyrazolic ligand: Preparation and characterization. Mater. Today Proc. 2022. [CrossRef]
  25. Kaddouri, Y.; Haddari, H.; Titi, A.; Yousfi, E.B.; Chetouani, A.; El Kodadi, M.; Touzani, R. Catecholase catalytic properties of copper (II) complexes prepared in-situ with heterocyclic ligands: Experimental and DFT study. Moroc. J. Chem. 2020, 8, 184–196. [Google Scholar] [CrossRef]
  26. Titi, A.; Al-Noaimi, M.; Kaddouri, Y.; El Ati, R.; Yousfi, E.B.; El Kodadi, M.; Touzani, R. Study of the catecholase catalytic properties of copper (II) complexes prepared in-situ with monodentate ligands. Mater. Today Proc. 2019, 13, 1134–1142. [Google Scholar] [CrossRef]
  27. El Ati, R.; Takfaoui, A.; El Kodadi, M.; Touzani, R.; Yousfi, E.B.; Almalki, F.A.; Ben Hadda, T. Catechol oxidase and Copper(I/II) Complexes Derived from Bipyrazol Ligand: Synthesis, molecular structure investigation of new biomimetic functional model and mechanistic study. Mater. Today Proc. 2019, 13, 1229–1237. [Google Scholar] [CrossRef]
  28. Boyaala, R.; El Ati, R.; Khoutoul, M.; El Kodadi, M.; Touzani, R.; Hammouti, B. Biomimetic oxidation of catechol employing complexes formed in situ with heterocyclic ligands and different copper(II) salts. J. Iran. Chem. Soc 2018, 15, 85–92. [Google Scholar] [CrossRef]
  29. Bouroumane, N.; El Kodadi, M.; Touzani, R.; El Boutaybi, M.; Oussaid, A.; Hammouti, B.; Nandiyanto, A.B.D. New pyrazole-based ligands: Synthesis, characterization, and catalytic activity of their copper complexes. Arab. J. Sci. Eng 2021, 47, 269–279. [Google Scholar] [CrossRef]
  30. Indira, S.; Vinoth, G.; Bharathi, M.; Bharathi, S.; Rahiman, A.K.; Bharathi, K.S. Catechol oxidase and phenoxazinone synthase mimicking activities of mononuclear Fe(III) and Co(III) complexes of aminobis(phenolate)-based mixed ligands: Synthesis, spectral and electrochemical studies. Inorg. Chim. Acta 2019, 495, 118988. [Google Scholar] [CrossRef]
  31. Lo, S.-I.; Lu, J.-W.; Chen, W.-J.; Wang, S.-R.; Wei, H.-H.; Katada, M. Functional model for catecholase-like activity: Synthesis, structure, spectra, and catalytic activity of iron (III) complexes with substituted-salicylaldimine ligands. Inorg. Chim. Acta 2009, 362, 4699–4705. [Google Scholar] [CrossRef]
  32. Megyes, T.; May, Z.; Schubert, G.; Grosz, T.; Simandi, L.I.; Radnai, T. Synthesis and structure study of some catecholase-mimetic iron complexes. Inorg. Chim. Acta 2006, 359, 2329–2336. [Google Scholar] [CrossRef]
  33. Simandi, L.I.; Simandi, T.M.; May, Z.; Besenyei, G. Catalytic activation of dioxygen by oximatocobalt (II) and oximatoiron (II) complexes for catecholase-mimetic oxidations of o-substituted phenols. Coord. Chem. Rev. 2003, 245, 85–93. [Google Scholar] [CrossRef]
  34. Majumder, S.; Mondal, S.; Lemoine, P.; Mohanta, S. Dinuclear mixed-valence Co III Co II complexes derived from a macrocyclic ligand: Unique example of a Co III Co II complex showing catecholase activity. Dalton Trans. 2013, 42, 4561–4569. [Google Scholar] [CrossRef]
  35. Banerjee, A.; Guha, A.; Adhikary, J.; Khan, A.; Manna, K.; Dey, S.; Zangrando, E.; Das, D. Dinuclear cobalt (II) complexes of Schiff-base compartmental ligands: Syntheses, crystal structure and bio-relevant catalytic activities. Polyhedron 2013, 60, 102–109. [Google Scholar] [CrossRef]
  36. Zhang, Y.; Meng, X.G.; Liao, Z.R.; Li, D.F.; Liu, C.L. Synthesis, structures and polyphenol oxidase activities of dicopper and dicobalt complexes. J. Coord. Chem. 2009, 62, 876–885. [Google Scholar] [CrossRef]
  37. Titi, A.; Warad, I.; Tillard, M.; Touzani, R.; Messali, M.; El Kodadi, M.; Eddike, D.; Zarrouk, A. Inermolecular interaction in [C6H10N3] 2 [CoCl4] complex: Synthesis, XRD/HSA relation, spectral and catecholase catalytic analysis. J. Mol. Struct. 2020, 1217, 128422. [Google Scholar] [CrossRef]
  38. Titi, A.; Shiga, T.; Oshio, H.; Touzani, R.; Mouslim, M.; Warad, I. Synthesis of novel Cl2Co4L6 clusterusing 1-hydroxymethyl-3,5-dimethylpyrazole (LH) ligand: Crystal structure, spectral, thermal, Hirschfeld surface analysis and catalytic oxidation evaluation. J. Mol. Struct. 2020, 1199, 126995. [Google Scholar] [CrossRef]
  39. Maji, A.K.; Ghosh, B.K.; Kaur, G.; Roy Choudhury, A.; Lin, C.-H.; Ribas, J.; Ghosh, R.; Mitra, M. Synthesis, crystallographic characterization and catecholase activity of a monocopper (II) and a dimanganese (III) complex with an anionic Schiff base ligand. Polyhedron 2013, 61, 15–19. [Google Scholar]
  40. Jana, A.; Aliaga-Alcalde, N.; Ruiz, E.; Mohanta, S. Structures, magnetochemistry, spectroscopy, theoretical study, and catechol oxidase activity of dinuclear and dimer-of-dinuclear mixed-valence MnIIIMnII complexes derived from a macrocyclic ligand. Inorg. Chem. 2013, 52, 7732–7746. [Google Scholar] [CrossRef]
  41. Seth, P.; Das, L.K.; Drew, M.G.B.; Ghosh, A. Synthesis, Crystal Structure, and Catecholase Activity of Three Trinuclear Heterometallic Ni2II–MnII Complexes Derived from a Salen-Type Schiff Base Ligand. Eur. J. Inorg. Chem. 2012, 2012, 2232–2242. [Google Scholar] [CrossRef]
  42. Guha, A.; Banu, K.S.; Banerjee, A.; Ghosh, T.; Bhattacharya, S.; Zangrando, E.; Das, D. Bio-relevant manganese (II) compartmental ligand complexes: Syntheses, crystal structures and studies of catalytic activities. J. Mol. Catal. A Chem. 2011, 338, 51–57. [Google Scholar] [CrossRef]
  43. Banu, K.S.; Chattopadhyay, T.; Banerjee, A.; Mukherjee, M.; Bhattacharya, S.; Patra, G.K.; Zangrando, E.; Das, D. Mono-and dinuclear manganese (III) complexes showing efficient catechol oxidase activity: Syntheses, characterization and spectroscopic studies. Dalton Trans. 2009, 8755–8764. [Google Scholar] [CrossRef] [PubMed]
  44. Kaizer, J.; Barath, G.; Csonka, R.; Speier, G.; Korecz, L.; Rockenbauer, A.; Parkanyi, L. Catechol oxidase and phenoxazinone synthase activity of a manganese (II) isoindoline complex. J. Inorg. Biochem. 2008, 102, 773–780. [Google Scholar] [CrossRef]
  45. Kaizer, J.; Csonka, R.; Barath, G.; Speier, G. Synthesis, properties, and catecholase-like activity of the [1, 4-di (6′-methyl-2′-pyridyl) aminophthalazine] dimanganese (II) complex, Mn2 (6′ Me2PAP) 2Cl4. Transit. Met. Chem. 2007, 32, 1047–1050. [Google Scholar] [CrossRef]
  46. Majumder, A.; Goswami, S.; Batten, S.R.; El Fallah, M.S.; Ribas, J.; Mitra, S. Catalytic oxidation of 3, 5-di-tert-butylcatechol by a manganese (III) 18-azametallacrown-6 compound: Synthesis, crystal structure, fluorescence, magnetic and kinetic investigation. Inorg. Chim. Acta 2006, 359, 2375–2382. [Google Scholar] [CrossRef]
  47. Blay, G.; Fernandez, I.; Pedro, J.R.; Ruiz-Garcia, R.; Temporal-Sanchez, T.; Pardo, E.; Lloret, F.; Munoz, M.C. Chemistry and reactivity of dinuclear manganese oxamate complexes: Aerobic catechol oxidation catalyzed by high-valent bis (oxo)-bridged dimanganese (IV) complexes with a homologous series of binucleating 4, 5-disubstituted-o-phenylenedioxamate ligands. J. Mol. Catal. A Chem. 2006, 250, 20–26. [Google Scholar] [CrossRef]
  48. Hitomi, Y.; Ando, A.; Matsui, H.; Ito, T.; Tanaka, T.; Ogo, S.; Funabiki, T. Aerobic catechol oxidation catalyzed by a Bis (μ-oxo) dimanganese (III, III) complex via a manganese (II)− semiquinonate complex. Inorg. Chem. 2005, 44, 3473–3478. [Google Scholar] [CrossRef]
  49. Mukherjee, S.; Weyhermueller, T.; Bothe, E.; Wieghardt, K.; Chaudhuri, P. Dinuclear and mononuclear manganese (IV)-radical complexes and their catalytic catecholase activity. Dalton Trans. 2004, 3842–3853. [Google Scholar] [CrossRef]
  50. Triller, M.U.; Pursche, D.; Hsieh, W.-Y.; Pecoraro, V.L.; Rompel, A.; Krebs, B. Catalytic Oxidation of 3,5-Di-tert-butylcatechol by a Series of Mononuclear Manganese Complexes:  Synthesis, Structure, and Kinetic Investigation. Inorg. Chem. 2003, 42, 6274–6283. [Google Scholar] [CrossRef]
  51. Guha, A.; Chattopadhyay, T.; Paul, N.D.; Mukherjee, M.; Goswami, S.; Mondal, T.K.; Zangrando, E.; Das, D. Radical pathway in catecholase activity with zinc-based model complexes of compartmental ligands. Inorg. Chem. 2012, 51, 8750–8759. [Google Scholar] [CrossRef]
  52. Olivares, C.; Solano, F. New insights into the active site structure and catalytic mechanism of tyrosinase and its related proteins. Pigment Cell Melanoma Res. 2009, 22, 750–760. [Google Scholar] [CrossRef]
  53. Nikkhahi, M.; Souri, E.; Sarkhail, P.; Baeeri, M.; Mohammadhosseini, N. Evaluation of anti-tyrosinase activity of Allium ursinum extracts and their metal complexes. Acta Sci. Pol. Technol. Aliment. 2018, 17, 219–226. [Google Scholar]
  54. Available online: http://www.ccdc.cam.ac.uk/conts/retrieving.html (accessed on 1 November 2022).
  55. Titi, A.; Messali, M.; Alqurashy, B.A.; Touzani, R.; Shiga, T.; Oshio, H.; Fettouhi, M.; Rajabi, M.; Almalki, F.A.; Ben Hadda, T. Synthesis, characterization, X-ray crystal study and bioctivities of pyrazole derivatives: Identification of antitumor, antifungal and antibacterial pharmacophore sites. J. Mol. Struct. 2020, 1205, 127625. [Google Scholar] [CrossRef]
  56. Choi, S.; Kim, S.; Lee, H.-J.; Lee, H. Cadmium (II) complexes containing N’-substituted N,N-bispyrazolyl ligands: The formation of 4- and 5-coordinated monomers versus 6-coordinated dimer. Inorg. Chem. Commun. 2014, 44, 164. [Google Scholar] [CrossRef]
  57. APEX3; Version 2017.3-0; Bruker AXS, Inc.: Madison, WI, USA, 2017.
  58. Sheldrick, G.M. Acta Crystallogr. Sect. A Fundam. Crystallogr. 2015, 71, 3. [Google Scholar]
Catalysts 12 01642 g001 550
Figure 1. Ortep representation of RCOOET (the free ligand) and packing in the triclinic cell.
Figure 1. Ortep representation of RCOOET (the free ligand) and packing in the triclinic cell.
Catalysts 12 01642 g001
Catalysts 12 01642 g002 550
Figure 2. FT-IR spectra of: (pink) the ligand (RCOOET) and (green) [(Cl)2Msdn(RCOOET)].
Figure 2. FT-IR spectra of: (pink) the ligand (RCOOET) and (green) [(Cl)2Msdn(RCOOET)].
Catalysts 12 01642 g002
Catalysts 12 01642 g003 550
Figure 3. (a) TGA and (b) DTA curves for [(Cl)2Mn(RCOOET)].
Figure 3. (a) TGA and (b) DTA curves for [(Cl)2Mn(RCOOET)].
Catalysts 12 01642 g003
Catalysts 12 01642 g004 550
Figure 4. Absorption reading at 390 nm accompanying the [(Cl)2Mn(RCOOET)]-catalyzed oxidation of catechol to o-quinone, (a) [(Cl)2Mn(RCOOET)] formed in situ in MeOH, (b) pre-synthesized [(Cl)2Mn(RCOOET)] in MeOH, (c) pre-synthesized [(Cl)2Mn(RCOOET)] in THF and (d) [(Cl)2Mn(RCOOET)] formed in situ in THF.
Figure 4. Absorption reading at 390 nm accompanying the [(Cl)2Mn(RCOOET)]-catalyzed oxidation of catechol to o-quinone, (a) [(Cl)2Mn(RCOOET)] formed in situ in MeOH, (b) pre-synthesized [(Cl)2Mn(RCOOET)] in MeOH, (c) pre-synthesized [(Cl)2Mn(RCOOET)] in THF and (d) [(Cl)2Mn(RCOOET)] formed in situ in THF.
Catalysts 12 01642 g004
Catalysts 12 01642 g005 550
Figure 5. UV-visible spectra of absorbance of o-quinone from the oxidation of catechol in the presence of the [(Cl)2Mn(RCOOET)] in THF.
Figure 5. UV-visible spectra of absorbance of o-quinone from the oxidation of catechol in the presence of the [(Cl)2Mn(RCOOET)] in THF.
Catalysts 12 01642 g005
Catalysts 12 01642 g006 550
Figure 6. Correlation between reaction rate and catechol concentrations catalyzed by [(Cl)2Mn(RCOOET)].
Figure 6. Correlation between reaction rate and catechol concentrations catalyzed by [(Cl)2Mn(RCOOET)].
Catalysts 12 01642 g006
Catalysts 12 01642 g007 550
Figure 7. Lineweaver−Burk plot of 1/rate vs. 1/[catechol].
Figure 7. Lineweaver−Burk plot of 1/rate vs. 1/[catechol].
Catalysts 12 01642 g007
Catalysts 12 01642 g008 550
Figure 8. Phenol oxidation in the presence of (a) [(Cl)2Mn(RCOOET)] formed in situ and (b) pre-synthesized [(Cl)2Mn(RCOOET)] in MeOH.
Figure 8. Phenol oxidation in the presence of (a) [(Cl)2Mn(RCOOET)] formed in situ and (b) pre-synthesized [(Cl)2Mn(RCOOET)] in MeOH.
Catalysts 12 01642 g008
Catalysts 12 01642 g009 550
Figure 9. UV-visible spectrum of absorption of o-quinone in the presence of the pre-synthesized [(Cl)2Mn(RCOOET)] in MeOH.
Figure 9. UV-visible spectrum of absorption of o-quinone in the presence of the pre-synthesized [(Cl)2Mn(RCOOET)] in MeOH.
Catalysts 12 01642 g009
Catalysts 12 01642 sch001 550
Scheme 1. The proposed catalytic mechanism for the oxidation reaction of catechol.
Scheme 1. The proposed catalytic mechanism for the oxidation reaction of catechol.
Catalysts 12 01642 sch001
Catalysts 12 01642 sch002 550
Scheme 2. Synthesis of the ligand, RCOOET.
Scheme 2. Synthesis of the ligand, RCOOET.
Catalysts 12 01642 sch002
Catalysts 12 01642 sch003 550
Scheme 3. Synthetic route of [(Cl)2Mn(RCOOET)].
Scheme 3. Synthetic route of [(Cl)2Mn(RCOOET)].
Catalysts 12 01642 sch003
Catalysts 12 01642 sch004 550
Scheme 4. Biochemical oxidation of phenol/catechol by catecholase (bottom) and tyrosine (top) [14].
Scheme 4. Biochemical oxidation of phenol/catechol by catecholase (bottom) and tyrosine (top) [14].
Catalysts 12 01642 sch004
Table
Table 1. Crystal data and structure refinement for C14H17N5O4.
Table 1. Crystal data and structure refinement for C14H17N5O4.
FormulaC14H17N5O4
CCDC1912583
Space group, P 1 ¯
Z, Formula weight 2, 318.33
Temperature (K)298 (2)
Lattice (Å, °)a = 6.8641(3), b = 11.2751(6), c = 11.6535(6)
α = 112.886(2), β = 104.104(2), γ = 99.536(2)
Volume (Å3)770.87(7)
Crystal (mm)0.14 × 0.14 × 0.30
Recorded/unique reflections21,566/3384 [Rint = 0.0354]
Goodness-of-fit on F21.017
Final R1, wR2 indices [I > 2σ(I)]0.059, 0.1489
Δρ Fourier residuals (e.Å−3)0.25/−0.26
Table
Table 2. Mass losses.
Table 2. Mass losses.
CompoundTemperature (°C)Mass Loss (%)Proposed Lost Species
Cl2MnRCOOET0–825.35Solvent
82–1724.24Chlorine
172–27816.18C5H5N2
278–46719.77C3H5O2
467–63523.43C5H6N3
Table
Table 3. Oxidation rate of [(Cl)2Mn(RCOOET)] catalyzed oxidation of catechol (μmol.L−1.min−1).
Table 3. Oxidation rate of [(Cl)2Mn(RCOOET)] catalyzed oxidation of catechol (μmol.L−1.min−1).
ComplexMeOHTHF
Solvent
The synthesized complex0.163.74
the prepared complex in situ0.21.51
Table
Table 4. Values of the Vmax and Km of the reaction catalyzed by the complex in THF.
Table 4. Values of the Vmax and Km of the reaction catalyzed by the complex in THF.
ComplexVmax (μmol. L−1. min−1)Km (mol. L−1)
[(Cl)2Mn(RCOOET)]0.3070.083
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Boutaybi, M.E.; Titi, A.; Alzahrani, A.Y.A.; Bahari, Z.; Tillard, M.; Hammouti, B.; Touzani, R. Aerial Oxidation of Phenol/Catechol in the Presence of Catalytic Amounts of [(Cl)2Mn(RCOOET)], RCOOET= Ethyl-5-Methyl-1-(((6-Methyl-3-Nitropyridin-2-yl)Amino)Methyl)-1H-Pyrazole-3-Carboxylate. Catalysts 2022, 12, 1642. https://doi.org/10.3390/catal12121642

AMA Style

Boutaybi ME, Titi A, Alzahrani AYA, Bahari Z, Tillard M, Hammouti B, Touzani R. Aerial Oxidation of Phenol/Catechol in the Presence of Catalytic Amounts of [(Cl)2Mn(RCOOET)], RCOOET= Ethyl-5-Methyl-1-(((6-Methyl-3-Nitropyridin-2-yl)Amino)Methyl)-1H-Pyrazole-3-Carboxylate. Catalysts. 2022; 12(12):1642. https://doi.org/10.3390/catal12121642

Chicago/Turabian Style

Boutaybi, Mohamed El, Abderrahim Titi, Abdullah Y. A. Alzahrani, Zahra Bahari, Monique Tillard, Belkheir Hammouti, and Rachid Touzani. 2022. "Aerial Oxidation of Phenol/Catechol in the Presence of Catalytic Amounts of [(Cl)2Mn(RCOOET)], RCOOET= Ethyl-5-Methyl-1-(((6-Methyl-3-Nitropyridin-2-yl)Amino)Methyl)-1H-Pyrazole-3-Carboxylate" Catalysts 12, no. 12: 1642. https://doi.org/10.3390/catal12121642

APA Style

Boutaybi, M. E., Titi, A., Alzahrani, A. Y. A., Bahari, Z., Tillard, M., Hammouti, B., & Touzani, R. (2022). Aerial Oxidation of Phenol/Catechol in the Presence of Catalytic Amounts of [(Cl)2Mn(RCOOET)], RCOOET= Ethyl-5-Methyl-1-(((6-Methyl-3-Nitropyridin-2-yl)Amino)Methyl)-1H-Pyrazole-3-Carboxylate. Catalysts, 12(12), 1642. https://doi.org/10.3390/catal12121642

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop