KR20200140774A - Manganese(Ⅳ) bis(hydroxo) complex, preparation method thereof, and oxidation method of naphthalene derivative using the same - Google Patents

Abstract

The present invention relates to a manganese(IV)-bis(hydroxo) complex, a preparation method thereof, and a method for oxidizing a naphthalene derivative using the same. The complex represented by chemical formula 1: [Mn^IV(L)(OH)_2]^2+ provided in an aspect of the present invention can easily oxidize naphthalene and derivatives thereof, which are known to have low reactivity and be toxic substances, in the presence of an acid, and thus has an effect of converting naphthalene and derivatives thereof to 1,4-naphthoquinone with low toxicity.

Description

Manganese(IV) bis(hydroxo) complex, preparation method thereof, and oxidation method of naphthalene derivative using the same {Manganese(IV) bis(hydroxo) complex, preparation method thereof, and oxidation method of naphthalene derivative using the same}

The present invention relates to a manganese (IV) bis (hydroxyl) complex, a method for preparing the same, and a method for oxidizing a naphthalene derivative using the same.

Polycyclic aromatic hydrocarbons (PAHs) are genotoxic, mutagenic, and carcinogenic, so metabolic conversion of polycyclic aromatic hydrocarbons is of great interest in the field of environmental and biochemistry. Are receiving.

Three major decomposition pathways for microbial catabolism of polycyclic aromatic hydrocarbons are known as follows.

1) In the presence of dioxygenases, a pathway to form cis dihydrodiols by inserting dioxygen molecules into the aromatic ring;

2) the pathway for hydroxylation or epoxidation of aromatic compounds by cytochrome P450 via arene oxides; And

*3) A pathway that uses ligninases to oxidize polycyclic aromatic hydrocarbons to convert them to quinones and to break the ring.

This reaction can be carried out by metal-reactive oxygen species such as metal hydroxo, peroxo and oxo intermediates.

Naphthalene, a structurally stable polycyclic aromatic hydrocarbon, is a major component of coal- and tar-based industries, and is a highly toxic xenobiotic compound. However, naphthalene oxidation is very difficult due to the low reactivity and high oxidation potential of the aromatic C-H bond.

High-valent metal oxo species have been used for the oxidation of relatively weak polycyclic aromatic hydrocarbons such as anthracene. The Mn ^IV oxo complex disclosed in Non-Patent Document 1 ( J. Am. Chem. Soc. 2011 , 133 , 20088.) induced the oxidation of naphthalene, which was sluggish. Under catalytic reaction conditions, some iron catalysts have been studied for the purpose of inducing the oxidation of naphthalene, but a catalyst capable of easily inducing the oxidation of naphthalene has not been developed. Recently, high-valent metal hydroxo intermediates in lipoxygenase and ligninolytic enzymes have been proposed as reactive species.

In biomimetic studies, a small number of nonheme high-valent metal hydroxyl complexes were prepared, showing the reactivity to activate CH bonds on aliphatic substrates, but reported on the reactivity to aromatic molecules such as naphthalene. There is no bar.

Therefore, there is a demand for a complex capable of easily oxidizing naphthalene having genotoxicity, mutagenicity and carcinogenicity.

An object of the present invention is to provide a manganese (IV) bis (hydroxyl) complex that has low reactivity and can easily oxidize naphthalene known as a toxic substance to the human body.

Another object of the present invention is to provide a method for preparing the manganese (IV) bis (hydroxyl) complex.

Another object of the present invention is to provide a method of oxidizing a naphthalene derivative using the manganese (IV) bis (hydroxyl) complex.

To achieve the above object,

One aspect of the present invention provides a manganese (IV) bis (hydroxyl) complex comprising a compound represented by the following formula (1).

[Formula 1]

[Mn ^IV (L)(OH) ₂ ] ²⁺

(In Formula 1,

이고, L is

ego,

R ¹ and R ² are independently hydrogen, unsubstituted or substituted straight or branched C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl ego,

The substituted straight or branched C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl is halogen, hydroxy, nitro, nitrile, respectively. , C _1-3 alkyl and C _1-3 alkoxy substituted C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl).

Another aspect of the present invention is as shown in Scheme 1 below,

Preparing a compound represented by the following formula (1) by reacting a compound represented by the following formula (2) with iodosylbenzene (PhiO); It provides a method for producing a manganese (IV) bis (hydroxyl) complex comprising a compound represented by the following formula (1), including.

[Scheme 1]

(In the above Scheme 1,

이고, L is

ego,

R ¹ and R ² are independently hydrogen, unsubstituted or substituted straight or branched C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl ego,

The substituted straight or branched C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl is halogen, hydroxy, nitro, nitrile, respectively. , C _1-3 alkyl and C _1-3 alkoxy substituted C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl).

Another aspect of the present invention provides a method of oxidizing a naphthalene derivative using a manganese (IV) bis(hydroxyl) complex including the compound represented by Formula 1 above.

The complex represented by Formula 1 provided in one aspect of the present invention can easily oxidize naphthalene and its derivatives, which are known to have low reactivity and toxic substances, in the presence of an acid, and can be easily converted to 1,4-naphthoquinone with low toxicity. There is an effect.

1 is a diagram showing the ESI-MS spectrum of the [Mn(TBDAP)(OTf) ₂ )] (1-(OTf) ₂ ) complex prepared in Preparation Example 1. FIG.
FIG. 2 shows UV/Vis absorption spectra of the composite of Preparation Example 1 (black line) and the composite of Example 1 (red line) at -30°C and CF ₃ CH ₂ OH/acetone (1:3 v/v). It is a drawing, and the inset is X of Preparation Example 1 complex (4.0 mM, black line) obtained from 293K, CH ₃ CN/H ₂ O (4:1 v/v) and Example 1 complex (4.0 mM, red line). -Shows the band EPR spectrum.
Figure 3 is a view showing the ESI-MS spectrum of the Example 1 complex (0.10 mm) in CF ₃ CH ₂ OH / acetone (1: 3 v / v), inset is Example 1 complex- ¹⁶ O (red line) And Example 1 complex- ¹⁸ O (blue line) shows the isotope distribution pattern.
4 shows the change in the UV-vis spectrum caused by reacting the composite of Preparation Example 1 with CAN (cerium(IV) ammonium nitrate).
5 is a diagram showing an ORTEP diagram of the composite in Example 1. FIG.
Figure 6 is -30 ℃ and CF ₃ CH ₂ OH / acetone (v / v = 1: 3) conditions, Example 1 complex [Mn ^IV (TBDAP) (OH) ₂ ] ²⁺ (0.10 mM), [Fe ^II (phen) ₃ ](PF ₆ ) ₂ (0.10 mM) reacts with UV-vis spectrum changes, and the inset is due to the formation of [Fe ^III (phen) ₃ ] ³⁺ over time. Represents the absorption intensity in the 620 nm region.
Figure 7 is in the presence of HOTf (10 mM), -30 ℃ and CF ₃ CH ₂ OH / acetone (v / v = 1: 3) in the conditions, Example 1 complex [Mn ^IV (TBDAP) (OH) ₂ ] ²⁺ (0.50 mM) reacts with [Ru ^II (Cl-phen) ₃ ](PF ₆ ) ₂ (0.25 mM), resulting in a change in the UV-vis spectrum, and the inset shows [Ru ^III It shows the absorption intensity in the 650 nm region due to the formation of (Cl-phen) ₃ ] ³⁺ .
Figure 8 shows the UV/Vis spectrum change according to the reaction of the Example 1 complex (1.0 mM) and 50 equivalents of naphthalene in the presence of HOTf (10 mM), and the inset is in the absence of HOTf (black line), HOTf The time course of the reaction observed in terms of absorption at λ=380 nm when is present (red line) is shown.
9 shows k _obs (pseudo-first-order rate constants) according to the concentration of naphthalene (black circle) and naphthalene-d ₈ (red circle).
10 shows (a) naphthalene; (b) 1,4-naphthoquinone; (c) 1,4-naphthoquinone in the presence of 1,2,4,5-tetramethylbenzene, which is an internal standard; (d) In N ₂ atmosphere, 20° C., CD ₃ CN/D ₂ O (v/v = 9:1), in the presence of HOTf (10 mM), Example 1 complex [Mn ^IV (TBDAP)(OH) ₂ shows, ¹ H-NMR spectrum of the reaction solution sample obtained by the oxidation of naphthalene (10 mM) according to ²⁺ (1.0 mM).
11 shows naphthalene using [Mn ^IV (TBDAP)(OH) ₂ ] ²⁺ (1.0 mM) or [Mn ^IV (TBDAP) ( ¹⁸ OH) ₂ ] ²⁺ (1.0 mM) corresponding to Example 1 complex It shows the GC-MS spectrum of 1,4-naphthoquinone produced by oxidation of.
12 is a diagram showing a graph of log k ₂ for E _pc of naphthalene substituted with an X substituent (X = OH, OMe, Me, H).
13 is a diagram showing a mechanism of oxidation reaction of naphthalene using the composite of Example 1 in the presence of an acid.

Hereinafter, the present invention will be described in detail.

On the other hand, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. In addition, embodiments of the present invention are provided in order to more completely explain the present invention to those having average knowledge in the art. Furthermore, "including" certain elements throughout the specification means that other elements may not be excluded, but other elements may be included unless specifically stated to the contrary.

One aspect of the present invention provides a manganese (IV) bis (hydroxyl) complex comprising a compound represented by the following formula (1).

[Formula 1]

[Mn ^IV (L)(OH) ₂ ] ²⁺

(In Formula 1,

이고, L is

ego,

R ¹ and R ² are independently hydrogen, unsubstituted or substituted straight or branched C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl ego,

The substituted straight or branched C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl is halogen, hydroxy, nitro, nitrile, respectively. , C _1-3 alkyl and C _1-3 alkoxy substituted C _1-10 alkyl, C _3-10 cycloalkyl, C _6-10 aryl, or C _6-10 aryl C _1-3 alkyl).

On the other side,

Wherein R ¹ and R ² are independently unsubstituted or substituted linear or branched C _1-10 alkyl, or C _3-10 cycloalkyl,

The substituted straight or branched C _1-10 alkyl, or C _3-10 cycloalkyl is selected from the group consisting of halogen, hydroxy, nitro, nitrile, C _1-3 alkyl and C _1-3 alkoxy, respectively. One or more substituents to be substituted may be substituted C _1-10 alkyl, or C _3-10 cycloalkyl.

In another aspect,

The R ¹ and R ² are independently unsubstituted or substituted linear or branched C _1-10 alkyl, and the substituted linear or branched C _1-10 alkyl is halogen, hydroxy, C _1-3 alkyl And one or more substituents selected from the group consisting of C _1-3 alkoxy may be substituted C _1-10 alkyl.

On the other side,

The R ¹ and R ² are independently unsubstituted or substituted straight or branched C _1-5 alkyl, and the substituted straight or branched C _1-5 alkyl is halogen, hydroxy, C _1-3 alkyl And at least one substituent selected from the group consisting of C _1-3 alkoxy may be substituted C _1-5 alkyl.

In another aspect,

L is N,N'-di-tertbutyl-2,11-diaza[3.3](2,6)-pyridinophane (N,N'-di-tertbutyl-2,11-diaza[3.3]( 2,6)-pyridinophane).

The manganese (IV) bis(hydroxyl) complex including the compound represented by Formula 1 may be used for oxidation of a naphthalene derivative, and may exist together with a -divalent anion and an ionic bond. As an example, the -divalent anion may be [Ce ^IV (NO ₃ ) ₆ ] ^2- , but is not limited thereto.

Another aspect of the present invention is as shown in Scheme 1 below,

Preparing a compound represented by the following formula (1) by reacting a compound represented by the following formula (2) with iodosylbenzene (PhiO); It provides a method for producing a manganese (IV) bis (hydroxyl) complex comprising the compound represented by Formula 1, including.

[Scheme 1]

(In the above Scheme 1,

L is as defined in Formula 1).

The reaction according to Reaction Scheme 1 may be performed under a known organic solvent, and as an example, an organic solvent in which CF ₃ CH ₂ OH and acetone are mixed may be used, but is not limited thereto. In addition, the idosylbenzene is 0.5 to 2.5 equivalents, 0.7 to 2.5 equivalents, 0.9 to 2.5 equivalents, 1.0 to 2.5 equivalents, 0.5 to 2.0 equivalents, 0.5 to 1.5 equivalents, 0.5 to 1 equivalent of the compound represented by Formula 2 1.3 equivalents, 0.5 to 1.1 equivalents, 0.5 to 1.0 equivalents, 0.7 to 2.0 equivalents, 0.9 to 1.5 equivalents, and 1.0 to 1.2 equivalents may be used, but are not limited thereto. Further, the reaction is -70 to 20 ℃, -60 to 20 ℃, -50 to 20 ℃, -40 to 20 ℃, -30 to 20 ℃, -70 to 10 ℃, -70 to 0 ℃, -70 to -10°C, -70 to -20°C, -70 to -30°C, -60 to 10°C, -50 to 0°C, -40 to -10°C, and -35 to -25°C, It is not limited thereto.

In another aspect, the present invention uses CAN (cerium(IV) ammonium nitrate), instead of using the idosylbenzene, a manganese (IV) bis (hydroxo) complex comprising the compound represented by Formula 1 It provides a method of manufacturing. When using CAN (cerium(IV) ammonium nitrate), CAN is 5 to 11 equivalents, 6 to 11 equivalents, 7 to 11 equivalents, 8 to 11 equivalents, 5 to 10 equivalents, compared to 1 equivalent of the compound represented by Formula 2, 5 to 9 equivalents, 5 to 8 equivalents, 6.5 to 10 equivalents, and 7 to 9 equivalents, but are not limited thereto.

Another aspect of the present invention provides a method of oxidizing a naphthalene derivative using a manganese (IV) bis(hydroxyl) complex including the compound represented by Formula 1 above. In this case, the naphthalene derivative may be a compound represented by Formula 2 below.

[Formula 2]

(In Chemical Formula 2,

A ¹ and A ² are independently hydrogen, hydroxy, straight or branched C _1-10 alkyl, or straight or branched C _1-10 alkoxy).

On the other side,

The A ¹ and A ² may be independently hydrogen, hydroxy, straight or branched C _1-5 alkyl, or straight or branched C _1-5 alkoxy.

The oxidation reaction of naphthalene is preferably carried out in the presence of an acid. As shown in the mechanism of FIG. 13, in the presence of an acid, the manganese (IV) bis(hydroxyl) complex including the compound represented by Formula 1 receives H ⁺ and an oxidation reaction with naphthalene begins.

The acid may be used without particular limitation as long as it is an acid capable of providing H ⁺ to the manganese (IV) bis (hydroxyl) complex containing the compound represented by Formula 1, and as a specific example, HOTf (Triflic acid) is used. I can.

The complex represented by Formula 1 provided in one aspect of the present invention can easily oxidize naphthalene and its derivatives, which are known to have low reactivity and toxic substances, in the presence of an acid, and can be easily converted to 1,4-naphthoquinone with low toxicity. There is an effect, which is directly supported by the examples and experimental examples described later.

Hereinafter, the present invention will be described in detail through examples and experimental examples.

However, the Examples and Experimental Examples described below are merely illustrative of a part of the present invention, and the present invention is not limited thereto.

Preparation for experiment

All chemicals used in Preparation Examples, Examples, and Experimental Examples described later are Aldrich Chemical Co. Or Alfa Aesar Co. Purchased from, these have high purity and were used as such without further purification unless otherwise noted. The solvents acetonitrile (CH ₃ CN) and diethyl ether (Et ₂ O) were passed through a solvent purification column (JC Meyer Solvent Systems) before use. H ₂ ¹⁸ O (95% ¹⁸ O-enriched) is a trademark of ICON Services Inc. (Summit, NJ, USA) purchased and used. Iodosylbenzene (PhiO) and a 1-electron reducing agent, for example [Fe ^II (phen) ₃ ] ²⁺ and [Ru ^II (Cl-phen) ₃ ] ²⁺ were prepared and synthesized by a known method ( H. Saltzman, JG Sharefkin, Organic Syntheses Coll, 1973, 5, 658. / O. Fussa-Rydel, H.-T. Zhang, JT Hupp, CR Leidner, Inorg. Chem. 1989, 28, 1533). TBDAP (N,N'-di-tertbutyl-2,11-diaza[3.3](2,6)-pyridinophane: N,N'-di-tertbutyl-2,11-diaza[3.3](2 ,6)-pyridinophane) ligand was prepared by reacting 2,6-bis-(chloromethyl)pyridine and 2,6-bis[(N-tert-butylamino)methyl]-pyridine at 80°C. UV-vis spectra were recorded with a Hewlett Packard 8454 Diode Array Spectrophotometer equipped with a UNISOKU Scientific Instruments cryostat and/or circulating water bath for low temperature experiments. ESI-MS (Electrospray ionization mass spectra) was collected with a Waters (Milford, MA, USA) Acquity SQD quadrupole Mass instrument. The spray voltage was set to 2.5 kV and the capillary temperature was set to 80°C. EPR spectra were obtained with a JEOL JES-FA200 spectrometer (EPR parameters: 9.152 GHz, microwave power = 1.0 mW, modulation frequency = 100 kHz and sweep width = 0.6 T). ¹ H NMR spectrum was measured by DGIST's CCRF, Bruker AVANCE III-400 spectrometer. Electrochemical measurements were carried out in a mixture solvent of CF ₃ CH ₂ OH / acetone (v/v = 1:3) containing n-Bu ₄ NPF ₆ (TBAPF ₆ , 0.10M) as a supporting electrolyte and at 298 K. , Performed with a CHI600E electrochemical analyzer. The conventional three-electrode battery used a battery having a platinum working electrode (surface area 0.3 mm ² ), a platinum wire as a counter electrode, and an Ag/AgNO ₃ (0.010 M) electrode as a reference electrode. Platinum working electrodes (BAS) were polished with a BAS polished alumina suspension and rinsed with acetone and acetonitrile prior to use. The measured potential was recorded in relation to the Ag/AgNO ₃ (0.010M) reference electrode. All potentials (Ag/Ag ⁺ contrast) were converted into values compared to SCE using the ferrocene potential under the same conditions. All electrochemical measurements were carried out under an N ₂ atmosphere. Crystallographic analysis was performed with a SMART APEX II CCD equipped with a Mo X-ray tube on the CCRF of DGIST.

<Production Example 1> [Mn(TBDAP)(OTf) ₂ )] (1-(OTf) ₂ ) Composite manufacturing

In a glove box, in a chloroform solution (2.0 mL) in which TBDAP (0.1763 g, 0.5 mmol) is dissolved, Mn(OTf) ₂ (0.1853 g, 0.525 mmol) dissolved in CH ₃ CN (2.0 mL) Was added to prepare a composite of Preparation Example 1 (OTf = Triflate group). The colorless mixture was stirred at room temperature (20-23°C) for 6 hours. After filtering the resulting solution, Et ₂ O (30 mL) was added to the resulting solution to obtain a white powder. Yield: 0.2810 g (79%).

ESI-MS in CH ₃ CN (see Fig. 1): m/z = 224.2 for [Mn ^II (TBDAP)(CH ₃ CN)] ²⁺ (calculated m/z =224.1), 244.7 for [Mn ^II (TBDAP) (CH ₃ CN) ₂ ] ²⁺ (calculated m/z = 244.6), and m/z = 556.2 for [Mn ^II (TBDAP)(OTf)] ⁺ (calculated m/z = 556.1). Anal. Calcd for C ₄₈ H ₆₄ F ₁₂ Mn ₂ N ₈ O ₁₂ S ₄ : C, 40.85; H, 4.57; N, 7.94. Found: C, 40.7; H, 4.68; N, 7.85. X-ray crystallographically suitable crystals were obtained by slow diffusion of Et ₂ O from CH ₃ CN into the complex solution.

<Example 1> [Mn ^IV (TBDAP)(OH) ₂ ] ²⁺ Composite manufacturing

At -30°C, 1.5 equivalents of PhIO was added to the preparation example 1 complex solution (1.0 mM) dissolved in CF ₃ CH ₂ OH/acetone (v/v = 1:3) to obtain [Mn ^IV The (TBDAP)(OH) ₂ ] ²⁺ complex was prepared in the form of a green solution.

UV-Vis in CF ₃ CH ₂ OH/acetone (v/v = 1:3): λ _max (ε) = 834 nm (380 M ^-1 cm ^-1 ) (Fig. 2), UV-vis in CH ₃ CN /H ₂ O (v/v = 9/1): λ _max (ε) = 834 nm (470 M ^-1 cm ^-1 ). ESI-MS in CF ₃ CH ₂ OH/acetone (v/v = 1:3) (Fig. 3): m/z = 220.7 for [Mn ^IV (TBDAP)(OH) ₂ ] ²⁺ (calculated m/z = 220.6).

[Mn ^IV (TBDAP)( ¹⁸ OH) ₂ ] ²⁺ is H ₂ ¹⁸ O (98%, 5 μL) in PhI ¹⁶ O solution under CF ₃ CH ₂ OH/acetone (v/v = 1:3) solvent. PhI ¹⁸ O prepared by addition was prepared by reacting with [Mn ^II (TBDAP)(OTf) ₂ ].

Alternatively, in a solvent of -30° C. and CH ₃ CN/H ₂ O (v/v = 9:1), 1 equivalent of the Preparation Example 1 complex and 8 equivalents of CAN (cerium(IV) ammonium nitrate) were reacted. The [Mn ^IV (TBDAP)(OH) ₂ ] ²⁺ complex of Example 1 may also be prepared in the form of a green solution.

4 shows the change in the UV-vis spectrum that appears as the reaction with CAN (cerium(IV) ammonium nitrate).

As another method, on a solvent at 20° C. and CH ₃ CN/H ₂ O (v/v = 3:1), the Preparation Example 1 complex (0.352 g, 0.050 mmol) and CAN (0.223 g, 0.40 mmol) were By reacting, the [Mn ^IV (TBDAP)(OH) ₂ ] ²⁺ complex of Example 1 may be prepared in the form of a green solution. Crystallographically suitable X-ray crystals of [Mn ^IV (TBDAP)(OH) ₂ ]-[Ce ^IV (NO ₃ ) ₆ ] were obtained through the following method. More specifically, the green solution was cooled to -40°C, and then layered with Et ₂ O previously cooled under N ₂ to obtain green crystals. Crystal yield: 0.0048 g (10%).

<Experimental Example 1> [Mn ^IV (TBDAP)(OH) ₂ ] ²⁺ Evaluation of the structural properties of the composite

In order to evaluate the structural properties of the [Mn ^IV (TBDAP)(OH) ₂ ] ²⁺ complex prepared in Example 1, the following experiment was performed.

<1-1> UV-vis absorption spectrum, X-band EPR spectrum, ESI-MS spectrum, isotope distribution pattern evaluation

Using the aforementioned Hewlett Packard 8454 diode array spectrophotometer and Waters (Milford, MA, USA) Acquity SQD quadrupole Mass instrument, UV-vis absorption spectrum, X-band EPR spectrum, ESI-MS spectrum, and isotope distribution pattern were confirmed. , The results are shown in FIGS. 2, 3, and 4.

FIG. 2 shows UV/Vis absorption spectra of the composite of Preparation Example 1 (black line) and the composite of Example 1 (red line) at -30°C and CF ₃ CH ₂ OH/acetone (1:3 v/v). It is a drawing, and the inset is X of Preparation Example 1 complex (4.0 mM, black line) obtained from 293K, CH ₃ CN/H ₂ O (4:1 v/v) and Example 1 complex (4.0 mM, red line). -Shows the band EPR spectrum.

Figure 3 is a view showing the ESI-MS spectrum of the Example 1 complex (0.10 mm) in CF ₃ CH ₂ OH / acetone (1: 3 v / v), inset is Example 1 complex- ¹⁶ O (red line) And Example 1 complex- ¹⁸ O (blue line) shows the isotope distribution pattern.

4 shows the change in the UV-vis spectrum caused by reacting the composite of Preparation Example 1 with CAN (cerium(IV) ammonium nitrate).

The inset of FIG. 2 is X of the complex of Preparation Example 1 (4.0 mM, black line) obtained from 293K, CH ₃ CN/H ₂ O (4:1 v/v) and the complex of Example 1 (4.0 mM, red line). -Band EPR spectrum is shown, from which the Example 1 complex has a broad signal at g _∥ =4.32 and a 6-line ultrafine pattern centered at g _⊥ =1.99 (A _⊥ =10 mT) is S =3/2 Mn ^IV It can be seen that the ground state is represented, and on the contrary, the composite in Preparation Example 1 has a strong resonance at g _∥ =6.48 and a weak ultrafine pattern at g _⊥ =2.02 (A _⊥ =9 mT), which means that the composite of Preparation Example 1 has an S=5/2 Mn ^II center. Spectrum strength in contrast to Production Example 1 of this complex, the complex of Example 1 is different axial zero-field splitting is due to the anti-D (zero-field splitting terms D ).

The inset of FIG. 3 shows the isotopic distribution patterns of the Example 1 complex- ¹⁶ O (red line) and the Example 1 complex- ¹⁸ O (blue line), from which the Example 1 complex has two oxygen atoms. This is supported.

<1-2> X-ray crystallography

Preparation Example 1 composite suitable for X-ray diffraction, Example 1 composite-[Ce ^IV (NO ₃ ) ₆ ] single crystals (nylon loop, Hampton) in a cooper plate at -40 ℃ Research Co.) was used and mounted on a goniometer head in an N ₂ cryostream. Data collection was performed on a Bruker SMART APEX II CCD diffractometer equipped with a monochromator in the Mo Kα (λ = 0.71073Å) incident beam. The CCD data was integrated and expanded using the Bruker-SAINT software package, and the structure was analyzed and purified using SHEXTL V 6.12. The hydrogen atom was in the calculated position. Hydrogen atoms on the hydroxo groups were identified on the Fourier difference map. All non-hydrogen atoms were purified by anisotropic thermal parameters.

The crystallographic data of Preparation Example 1 complex, Example 1 complex-[Ce ^IV (NO ₃ ) ₆ ] are shown in Table 1 below, and specific binding distances and angles are shown in Table 2 below.

[Table 1]

[Table 2]

Example 1 The X-ray crystal structure of the complex [Mn(TBDAP)(OH) ₂ ][Ce-(NO ₃ ) ₆ ] is an octahedral geometry in which the mononuclear Mn bis(hydroxyl) complex is distorted. Supports the adoption of (see Fig. 5). The structural parameters of the [Ce(NO ₃ ) ₆ ] part are very similar to those of the [(NH ₄ ) ₂ Ce ^IV (NO ₃ ) ₆ ] complex, and support that the formal oxidation state of cerium is ⁴⁺ . In addition, the presence of one [Ce ^IV (NO ₃ ) ₆ ] ^2- counter ion per Mn atom in the crystal lattice means that the Mn center is in a ⁴⁺ oxidation state. In particular, the successful purification of Mn-O bond lengths (1.804 and 1.807 Å) and hydroxo groups clearly demonstrates the presence of the Mn(OH) ₂ moiety.

<Experimental Example 2> Evaluation of redox titration

In order to evaluate the one-electron reduction potential of the [Mn ^IV (TBDAP)(OH) ₂ ] ²⁺ complex prepared in Example 1, a redox titration experiment was performed.

More specifically, at -30°C and CF ₃ CH ₂ OH/acetone (v/v = 1:3) conditions, various concentrations of [Fe ^II (phen) ₃ ] ²⁺ (3.0 × 10 ^-5 to 1.5 × 10) ^-4 M), an electron transfer reaction of the Example 1 complex (1.0 × 10 ^-4 M) was performed. When a degassed acetone solution of [Fe ^II (phen) ₃ ] ²⁺ was added to the composite solution of Example 1, the UV-vis spectrum was changed at 620 nm due to [Fe ^III (phen) ₃ ] ³⁺ . The concentration of [Fe ^III (phen) ₃ ] ³⁺ was determined from the absorption band at 620 nm (ε=5.4×10 ² M ^-1 cm ^-1 ). The ε value of [Fe ^III (phen) ₃ ] ³⁺ is at -30°C and CF ₃ CH ₂ OH/acetone (v/v = 1:3), together with cerium ammonium nitrate (5 equivalents), [ It was measured by electron-transfer oxidation of Fe ^II (phen) ₃ ] ²⁺ .

In addition, in the presence of HOTf (10 mM), at -30° C. and CF ₃ CH ₂ OH/acetone (v/v = 1:3) conditions, various concentrations of [Ru ^II (Cl-phen) ₃ ] ²⁺ ( 1.25 × 10 ^-4 to 3.75 × 10 ^-4 M), an electron transfer reaction of the Example 1 complex (2.5 × 10 ^-4 M) was performed. When a degassed acetone solution of [Ru ^II (Cl-phen) ₃ ] ²⁺ was added to the composite solution of Example 1, the UV-vis spectrum due to [Ru ^III (Cl-phen) ₃ ] ³⁺ was found at 650 nm. Changed. The concentration of [Ru ^III (Cl-phen) ₃ ] ³⁺ was determined from the absorption band at 650 nm (ε=1.1×10 ³ M ^-1 cm ^-1 ). The ε value of [Ru ^III (Cl-phen) ₃ ] ³⁺ is at -30°C and CF ₃ CH ₂ OH/acetone (v/v = 1:3), in the presence of HOTf (10 mM) cerium ammonium Measured by electron-transfer oxidation of [Ru ^II (Cl-phen) ₃ ] ²⁺ with nitrate (3 equivalents).

Figure 6 is -30 ℃ and CF ₃ CH ₂ OH / acetone (v / v = 1: 3) conditions, Example 1 complex [Mn ^IV (TBDAP) (OH) ₂ ] ²⁺ (0.10 mM), [Fe ^II (phen) ₃ ](PF ₆ ) ₂ (0.10 mM) reacts with UV-vis spectrum changes, and the inset is due to the formation of [Fe ^III (phen) ₃ ] ³⁺ over time. Represents the absorption intensity in the 620 nm region. Example 1 The electron transfer reduction (ET reduction) of the complex was confirmed to be in equilibrium with [Fe ^II (phen) ₃ ] ^2+, and the final concentration of [Fe ^III (phen) ₃ ] ³⁺ was [Fe ^II (phen) ) ₃ ] Increased as the initial concentration of ²⁺ increased. The equilibrium constant ( K _et ) was determined to be 1.38, and the one-electron reduction potential ( E _red ) of the Example 1 complex was 1.09 V vs. Nernst equation. It was decided by SCE. The one-electron reduction potential value of 1.09 V of the Example 1 complex is a very good value that has not been achieved by all known nonheme Mn ^IV bis-(hydroxyl) and Mn ^IV oxo intermediates.

Figure 7 is in the presence of HOTf (10 mM), -30 ℃ and CF ₃ CH ₂ OH / acetone (v / v = 1: 3) in the conditions, Example 1 complex [Mn ^IV (TBDAP) (OH) ₂ ] ²⁺ (0.50 mM) reacts with [Ru ^II (Cl-phen) ₃ ](PF ₆ ) ₂ (0.25 mM), resulting in a change in the UV-vis spectrum, and the inset shows [Ru ^III It shows the absorption intensity in the 650 nm region due to the formation of (Cl-phen) ₃ ] ³⁺ . The equilibrium constant ( K _et ) of the Example 1 complex and [Ru ^II (Cl-phen) ₃ ] ²⁺ was determined to be 1.73, and one-electron reduction of the Example 1 complex in the presence of HOTf (10 mM) The potential value ( E _red ) is determined by using the Nernst equation to determine 1.41 V vs. It was decided by SCE.

From this, the one-electron reduction potential value ( E _red ) of the complex of Example 1 was 1.09 V vs. when HOTf (10 mM) was not present. It was SCE, but the one-electron reduction potential value ( E _red ) in the presence of HOTf (10 mM) was 1.41 V vs. It can be seen that it can move largely with SCE, that is, in a positive direction.

<Experimental Example 3> Evaluation of naphthalene oxidation-inducing activity

In consideration of the very good one-electron reduction potential value of the Example 1 composite, it was evaluated whether the Example 1 composite could induce the oxidation of naphthalene.

More specifically, the reaction was induced by adding an excess (50 equivalents) of naphthalene to the Example 1 complex (1.0 mM) under a mixed solvent of -30°C and CF ₃ CH ₂ OH/acetone (1:3 v/v). As a result, it was found that naphthalene and the composite of Example 1 did not react.

On the other hand, as a result of inducing the same reaction in the presence of HOTf (10 mM), as the Example 1 complex and naphthalene reacted, a remarkable change in the absorption band appeared as a first-order decay profile (Fig. 8). ).

Figure 8 shows the UV/Vis spectrum change according to the reaction of the Example 1 complex (1.0 mM) and 50 equivalents of naphthalene in the presence of HOTf (10 mM), and the inset is in the absence of HOTf (black line), HOTf When is present (red line), it shows the absorption intensity at λ=380 nm over the course of the reaction time. Meanwhile, k _obs (pseudo-first-order rate constants) increased linearly with increasing naphthalene concentration (Fig. 9), and k ₂ (second-order rate constant) at -30°C was 7.3(6)× It was 10 ^-1 M ^-1 s ^-1 .

As a result of the reaction, it was confirmed through ¹ H NMR spectrum that naphthalene was converted to 1,4-naphthoquinone, and it was confirmed that the conversion yield was also very good at 90% (FIG. 10). . 10 shows (a) naphthalene; (b) 1,4-naphthoquinone; (c) 1,4-naphthoquinone in the presence of 1,2,4,5-tetramethylbenzene, which is an internal standard; (d) In N ₂ atmosphere, 20° C., CD ₃ CN/D ₂ O (v/v = 9:1), in the presence of HOTf (10 mM), Example 1 complex [Mn ^IV (TBDAP)(OH) ₂ shows, ¹ H-NMR spectrum of the reaction solution sample obtained by the oxidation of naphthalene (10 mM) according to ²⁺ (1.0 mM). In FIG. 10, * is a peak due to an internal standard of 1,2,4,5-tetramethylbenzene. In addition, when naphthalene was oxidized to the Example 1 complex- ¹⁸ O, it was confirmed that the oxygen atom in the product 1,4-naphthoquinone was derived from the Example 1 complex (FIG. 11).

<Experimental Example 4> Evaluation of the oxidation-inducing activity of naphthalene substituted with the X substituent

The same experiment as in Experimental Example 3 was performed, but the oxidation reaction was performed on naphthalene in which the X substituent was substituted instead of naphthalene, and the change in the degree of oxidation reaction according to the presence of the substituent was confirmed. As the X substituent, OH, OMe, Me or H was adopted. (I.e. 1-naphthol, 1-methoxynaphthalene, 1-methylnaphthalene, naphthalene)

As a result, when plotting the electron transfer rate with respect to the oxidation potential ( E _pc ) of the naphthalene derivative, a good linear correlation was obtained, and a negative slope of -3.7 was derived (Fig. 12). These results support that naphthalene acid-accelerated oxidation using the Example 1 composite occurs through the rate-determining electron transport pathway.

In the presence of acid, the oxidation reaction mechanism of naphthalene using the Example 1 composite is shown in FIG. 13.

From this, the complex represented by Formula 1 provided in one aspect of the present invention easily oxidizes naphthalene and its derivatives, which are known to have low reactivity and toxic substances, in the presence of acid, and thus easily become 1,4-naphthoquinone with low toxicity. It can be seen that there is an effect that can be converted.

Claims (4)

As shown in Scheme 1 below,
Preparing a compound represented by the following formula (1) by reacting a compound represented by the following formula (2) with iodosylbenzene (PhiO); A method of preparing a manganese (IV) bis (hydroxyl) complex, which is a compound represented by the following Formula 1, including:
[Scheme 1]

(In the above Scheme 1,
L is

ego,
R ¹ and R ² are independently unsubstituted or substituted straight or branched C _1-5 alkyl,
And the substituted straight- or branched-chain C _1-5 alkyl is alkyl of _1-5 is one or more substituents selected from halogen, hydroxy, C _1-3 alkyl and C _1-3 alkoxy substituted by the group consisting of C,
OTf is trifluoromethylsulfonyl).
A method of oxidizing a naphthalene derivative represented by the following formula (2) using a manganese (IV) bis(hydroxyl) complex, a compound represented by the following formula (1):
[Formula 1]
[Mn ^IV (L)(OH) ₂ ] ²⁺
(In Formula 1,
L is

ego,
R ¹ and R ² are independently unsubstituted or substituted straight or branched C _1-5 alkyl,
The C _1-5 alkyl-substituted straight-chain or branched-chain halogen, hydroxy, C _1-3 alkyl and C _1-3 alkoxy are one or more substituents selected from the group consisting of substituted C _1-5 alkyl) ,
[Formula 2]

(In Chemical Formula 2,
A ¹ and A ² are independently hydrogen, hydroxy, straight or branched C _1-10 alkyl, or straight or branched C _1-10 alkoxy).
The method of claim 2,
The method of oxidizing a naphthalene derivative, wherein A ¹ and A ² are independently hydrogen, hydroxy, straight or branched C _1-5 alkyl, or straight or branched C _1-5 alkoxy.
The method of claim 2,
The method of oxidizing a naphthalene derivative, characterized in that the oxidation of the naphthalene derivative is performed in the presence of an acid.

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