Imine pyridine macrocyclic iron complex as well as preparation method and application thereof

Abstract

The invention discloses an imine pyridine macrocyclic iron complex as well as a preparation method and application thereof. The structure of the compound is shown as a formula I. The compound shown in the formula I provided by the invention can be synthesized through a simple and efficient method: in an organic solvent, a diamine compound and p-di (formyl pyridyl) benzene are prepared through a nucleophilic addition elimination reaction. The synthesis method has the characteristics of cheap and easily available raw materials, simplicity and convenience in operation, high reaction efficiency, mild reaction conditions, stable product and easiness in separation and preparation. And the tetra-imine tetrapyridine diiron macrocyclic complex has good performance and application prospect in the field of lingering type self-classification. # imgabs0 #

Description

Technical Field

[0001] The invention belongs to the field of organic chemistry, and specifically relates to a macrocyclic diiron complex with tetraimine tetrapyridine units and a preparation method and application thereof. Background Art

[0002] Iron complexes have been widely used in organic synthesis in recent years due to their rich valence states and diverse coordination modes. In 2010, M. Christina White et al. discovered that the iron complex Fe-PDP has extremely high catalytic oxidation activity, and subsequently developed a series of CH bond oxidation reactions at different positions and asymmetric epoxidation reactions of carbon-carbon double bonds (Mark S. Chen, M. Christina White,. Science. 1973, 29, 327.). After a long period of development, iron-porphyrin complexes play an important role in single-electron oxidation reactions, which is of great significance for revealing the mechanism of such reactions (Pritam Mondal, Gayan B. Wijeratne, J. Am. Chem. Soc. 2020, 142, 4, 1846–1856.). Fe-Salen complexes are currently well used in various oxidation and functionalization reactions.

[0003] At present, the template method for synthesizing various metal complexes is becoming more and more popular. From the synthesis of catenanes to the synthesis of various symmetrical / complex structures, the template method is known for its simplicity and efficiency. There is a special self-classification property in the system synthesized by the template method (including narcissistic self-classification, interactive self-classification and comprehensive self-classification) (Jean Ayme, Sebastien Dhers, Jean Lehn, Angew. Chem. Int. Ed. 2020, 59, 12484–12492). Both template synthesis and novel self-classification properties are currently widely studied, and have broad prospects and potential application value in the synthesis and application of various complex systems. Summary of the invention

[0004] The purpose of the present invention is to provide a class of iminopyridine macrocyclic iron complexes and a preparation method thereof.

[0005] The iminopyridine macrocyclic iron complex provided by the present invention has a general structural formula as shown in Formula I:

[0006]

[0007] In formula I, R is independently selected from any one of the following groups: hydrogen, deuterium, C 1 -C 6Straight-chain or branched alkyl groups (eg, -Me, -Bu), aryl groups (eg, -Ph) and benzyl groups (-Bn).

[0008] The present invention also provides a method for preparing the iminopyridine macrocyclic iron complex.

[0009] The preparation method of the iminopyridine macrocyclic iron complex provided by the present invention comprises the following steps:

[0010] The compound represented by formula II and the compound represented by formula III are subjected to a nucleophilic addition elimination reaction under the condition of ferrous trifluoromethanesulfonate as a template to obtain a compound represented by formula I;

[0011]

[0012] The compound represented by formula II can specifically be any one of the following compounds:

[0013]

[0014] In formula III, R is independently selected from any one of the following groups: hydrogen, deuterium, C 1 -C 6 Straight-chain or branched alkyl (e.g., -Me, -Bu), aryl (e.g., -Ph), and benzyl (-Bn);

[0015] In the above method, the nucleophilic addition elimination reaction is carried out in an organic solvent.

[0016] The organic solvent may specifically be acetonitrile;

[0017] The molar ratio of the compound represented by formula II to the compound represented by formula III and ferrous trifluoromethanesulfonate can be: 1-1.2:1:1-1.2, specifically 1:1:1;

[0018] The reaction temperature can be 70-90°C, and the reaction time can be 8-16 hours, specifically, the reaction can be carried out at 90°C for 12 hours.

[0019] The iminopyridine macrocyclic iron complex shown in the above formula I has the performance of narcissistic self-classification.

[0020] The iminopyridine macrocyclic iron complex shown in Formula I exhibits a strong CD signal, and therefore, its use as or for preparing chiral ferromagnetic materials also falls within the protection scope of the present invention.

[0021] The invention selects cheap and readily available raw materials, and prepares a macrocyclic iron complex showing a strong CD signal from readily available reagents such as ethylenediamine, cyclohexanediamine and ferrous trifluoromethanesulfonate. The reaction conditions are relatively mild, the obtained product is stable in the air and easy to separate, the yield is extremely high, and the invention has good practicality and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is the reaction formula for preparing the macrocyclic complex represented by formula I-1 in Example 1 of the present invention.

[0023] Figure 2 This is the reaction formula for preparing the macrocyclic complex represented by formula I-2 in Example 2 of the present invention.

[0024] Figure 3 This is the reaction formula for preparing the macrocyclic complex represented by formula I-3 in Example 3 of the present invention.

[0025] Figure 4 This is the reaction formula involved in the narcissistic self-classification performance detection in Example 4 of the present invention.

[0026] Figure 5 This is the NMR spectrum of the product obtained in Example 4 of the present invention.

[0027] Figure 6 This is the CD signal diagram of the macrocyclic complex represented by formula I-2 prepared in Example 2 of the present invention.

[0028] Figure 7 This is the CD signal diagram of the macrocyclic complex represented by formula I-3 prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with specific embodiments, and the examples provided are only for illustrating the present invention, rather than for limiting the scope of the present invention. The examples provided below can be used as a guide for further improvements by those of ordinary skill in the art, and do not constitute a limitation of the present invention in any way.

[0030] The experimental methods in the following examples, unless otherwise specified, are all conventional methods, and are performed according to the techniques or conditions described in the literature in the field or according to the product instructions. The materials, reagents, etc. used in the following examples, unless otherwise specified, can all be obtained from commercial channels.

[0031] Example 1: Preparation of the macrocyclic complex represented by formula I-1

[0032] The reaction is as Figure 1 shown.

[0033] The specific preparation method is:

[0034] Add magnet, ethylenediamine (60 mg, 1 mmol), p-di(aldehyde pyridyl)benzene (288 mg, 1 mmol), ferrous trifluoromethanesulfonate (354 mg, 1 mmol) and 100 mL acetonitrile to a clean two-necked bottle. React at 90°C for 12 hours. The solvent is dried by spin drying to obtain the product, with a yield of 99%.

[0035] 1 H NMR (Acetonitrile-d 3 / 300MHz)δ9.75(s,4H),9.39(s,4H),8.70(dd,4H),8.32(m,12H),4.85(s,8H),3.28(s,6H);

[0036] From the above, it can be seen that the structure of the above compound is correct, and it is the compound shown in formula I-1.

[0037] Example 2: Preparation of the macrocyclic complex represented by formula I-2

[0038] The reaction is as Figure 2 shown.

[0039] The specific preparation method is:

[0040] Add magnet, cyclohexanediamine (108 mg, 1 mmol), p-di(aldehyde pyridyl)benzene (288 mg, 1 mmol), ferrous trifluoromethanesulfonate (354 mg, 1 mmol) and 100 mL acetonitrile to a clean two-necked bottle. React at 90°C for 12 hours. The solvent is dried by spin drying to obtain the product, with a yield of 99%.

[0041] 1 H NMR (Acetonitrile-d 3 / 300MHz)δ9.78(s,4H),9.36(s,4H),8.73(dd,4H),8.35(m,12H),4.22(s,4H),3.04(s,6H),2.20(s,8H),1.08(s,8H);

[0042] From the above, it can be seen that the structure of the above compound is correct, and it is the compound shown in formula I-2.

[0043] Example 3: Preparation of the macrocyclic complex represented by formula I-3

[0044] The reaction is as Figure 3 shown.

[0045] The specific preparation method is:

[0046] Add magnetron, (S,S)-diphenyldiamine (212 mg, 1 mmol), p-di(aldehyde pyridyl)benzene (288 mg, 1 mmol), ferrous trifluoromethanesulfonate (354 mg, 1 mmol) and 100 mL acetonitrile to a clean two-necked bottle. React at 90°C for 12 hours. The solvent is dried by spin drying to obtain the product, with a yield of 99%.

[0047] 1 H NMR (Acetonitrile-d 3 / 300MHz)δ9.86(s,4H),8.94(s,4H),8.72(d,4H),8.42(s,8H),8.24(d,4H),7.55(s,20H),5.99(s,4H);

[0048] From the above, it can be seen that the structure of the above compound is correct, and it is the compound shown in formula I-3.

[0049] Example 4: Narcissistic self-classification performance test

[0050] The tetraimine tetrapyridine diiron macrocyclic diiron complexes with different connecting arms prepared by the present invention are used to achieve narcissistic self-classification performance:

[0051] We synthesized this series of molecular cages by mixing the connecting arms and reacting them with dialdehyde compounds, and the system will have interesting narcissistic self-classification properties. From the NMR results: the NMR of the system is a superposition of the NMR spectra of several diamine macrocycles of the same type, indicating that there are only macrocycles with the same diamine connecting arms in the system, and there are no macrocyclic complexes of various diamine hybrids (reaction formula is as follows Figure 4 Mass spectrometry results (as shown). Figure 5 The same is true for the system shown in Figure 1. The mass spectrum of the system also only has macrocycles with the same diamine linker, and no mass spectrum peaks of hybrid macrocycles appear. Related mass spectrum peaks: MS: m / z calcd: 601.2, Found: 601.2; calcd: 870.2, Found: 870.3; calcd: 1133.3, Found: 1133.3. This type of narcissistic self-classification system is currently less developed, especially for ethylenediamine and cyclohexanediamine, which can achieve completely identical linkers in conformation, and this is the first report of narcissistic self-classification.

[0052] The specific preparation method is:

[0053] Add magnetron, ethylenediamine (60 mg, 1 mmol), (S,S)-cyclohexanediamine (212 mg, 1 mmol), (S,S)-diphenyldiamine (212 mg, 1 mmol), p-di(aldehyde pyridyl)benzene (288 mg, 1 mmol), ferrous trifluoromethanesulfonate (354 mg, 1 mmol) and 100 mL acetonitrile to a clean two-necked bottle. React at 90°C for 12 hours. Spin dry the solvent for NMR and mass spectrometry monitoring.

[0054] Example 5: Performance Testing

[0055] Take 1 mg (0.7 μmol) of the complex (Formula I-2) and dissolve it in 3 mL of acetonitrile. Pour the solution into a cuvette and put it into a CD spectrometer to collect the spectrum. Figure 6 .

[0056] Take 1 mg (0.6 μmol) of the complex (Formula I-3) and dissolve it in 3 mL of acetonitrile. Pour the solution into a cuvette and put it into a CD spectrometer to collect the spectrum. Figure 7 .

[0057] Judging from the CD signal results, its CD signals are relatively strong, and these signals mainly correspond to the absorption of the coordination bonds of iron ions, which indicates that the chiral environment around iron is strong, indicating that the compound is a potential chiral ferromagnetic material.

[0058] The present invention has been described in detail above. For those skilled in the art, without departing from the purpose and scope of the present invention, and without the need to carry out unnecessary experimental conditions, the present invention can be implemented in a wide range under equivalent parameters, concentrations and conditions. Although the present invention provides specific embodiments, it should be understood that the present invention can be further improved. In a word, according to the principles of the present invention, the application is intended to include any changes, uses or improvements to the present invention, including departure from the disclosed scope in the application, and changes made with conventional techniques known in the art.

Claims

1. Iminopyridine macrocyclic iron complex, the general structural formula of which is shown in Formula I: In formula I, R is independently selected from any one of the following groups: hydrogen, deuterium, C1-C6 straight or branched chain alkyl, aryl and benzyl.

2. A method for preparing the iminopyridine macrocyclic iron complex of formula I in claim 1, comprising the following steps: subjecting the compound of formula II to a nucleophilic addition elimination reaction with the compound of formula III under the condition of ferrous trifluoromethanesulfonate as a template to obtain a compound of formula I; The compound represented by formula II is any one of the following compounds: In formula III, R is independently selected from any one of the following groups: hydrogen, deuterium, C1-C6 straight or branched chain alkyl, aryl and benzyl.

3. The method according to claim 2, characterized in that: The nucleophilic addition elimination reaction is carried out in an organic solvent.

4. The method according to claim 3, characterized in that: The organic solvent is acetonitrile.

5. The method according to claim 2, characterized in that: The molar ratios of the compound represented by formula II, the compound represented by formula III and ferrous trifluoromethanesulfonate are: 1-1.2:1:1-1.

2.

6. The method according to claim 5, characterized in that: The molar ratio of the compound represented by formula II, the compound represented by formula III and ferrous trifluoromethanesulfonate is 1:1:

1.

7. The method according to claim 2, characterized in that: The reaction temperature is 70-90°C and the reaction time is 8-16h.

8. Use of the iminopyridine macrocyclic iron complex of formula I in claim 1 as or in the preparation of chiral ferromagnetic materials.

9. The iminopyridine macrocyclic iron complex of formula I in claim 1 has the property of narcissistic self-classification.

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