RU2349575C1 - Method of producing 1-hydroxy-1,2-dihydro[60]fullerene - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: present invention pertains to organic chemistry, particularly to the method of producing functionally substituted fullerenes, which can be used as complexing agents, sorbents, biologically active compounds, as well as in making new materials with given properties. The essence of the method lies in reaction of fullerene C₆₀ with water in the presence of a Cp₂ZrCl₂ catalyst in a toluene medium at 70-90°C temperature for a period of 0.5-1.5 hours.

EFFECT: selective method of producing 1-hydroxy-1,2-dihydro[60]fullerene, with 72-94% output of the target product.

9 ex, 1 tbl

Description

The present invention relates to organic chemistry, specifically, to a method for producing 1-hydroxy-1,2-dihydro [60] fullerene of the general formula (1):

Functionally substituted fullerenes can be used as complexing agents, sorbents, biologically active compounds, as well as in the creation of new materials with desired properties.

A known method ([1], LYChiang, LYWang, S.-M.Tseng, J.-S.Wu, K.-H.Hsieh. J.Chem.Soc., Chem.Commun., 1994, 2675) to obtain a mixture fullerenols of the formula (2) by reaction With ₆₀ with a reagent H ₂ SO ₄ · SO ₃ followed by hydrolysis of the reaction mass with water according to the scheme:

The known method leads to the formation of a complex mixture of fullerenols (2) and does not allow to selectively obtain 1-hydroxy-1,2-dihydro [60] fullerene (1).

A known method ([2], NSSchneider, AD Darwish, HWKroto, R. Taylor, DRM Walton. J. Chem. Soc., Chem. Commun., 1994, 463) to obtain a mixture of fullerenols of the formula (3) by hydroboration of C ₆₀ in tetrahydrofuran followed by oxidation the reaction mass using alkaline hydrogen peroxide according to the scheme:

In a known manner, individual 1-hydroxy-1,2-dihydro [60] fullerene (1) cannot be obtained.

Thus, in the literature there is no information on the selective synthesis of 1-hydroxy-1,2-dihydro [60] fullerene (1).

A new method for the selective production of 1-hydroxy-1,2-dihydro [60] fullerene (1) is proposed.

The essence of the method consists in the interaction of fullerene C ₆₀ with water (H ₂ O) in the presence of a catalyst of zirconacene dichloride (Cp ₂ ZrCl ₂ ), taken in a molar ratio of respectively 0.01: (45-65) :( 0.0015-0.0025), preferably 0.01: 55: 0.0020, at a temperature of 70-90 ° C for 0.5-1.5 hours, preferably 1 hour, in a toluene solution. The yield of 1-hydroxy-1,2-dihydro [60] fullerene (1) is 72-94% (according to HPLC). The reaction proceeds according to the scheme:

Water is taken with a large excess in relation to fullerene C ₆₀ in order to increase the yield of the target product (1). A decrease in the amount of water with respect to C _{60 is} impractical, since it leads to a decrease in the yield of the target product.

1-Hydroxy-1,2-dihydro [60] fullerene (1) is formed only with the participation of fullerene [60] and water under the action of the catalyst Cp ₂ ZrCl ₂ .

Carrying out this reaction in the presence of a zirconium catalyst Cp ₂ ZrCl ₂ more than 0.0025 mol fractions with respect to C ₆₀ does not significantly increase the yield of the target product (1). The use of the catalyst Cp ₂ ZrCl ₂ less than 0.0015 molar fractions with respect to C ₆₀ reduces the yield of the product (1), which is possibly associated with a decrease in the catalytically active centers in the reaction mass.

A change in the ratio of the starting reagents towards a significant increase in the water content with respect to fullerene [60] does not lead to a significant increase in the yield of 1-hydroxy-1,2-dihydro [60] fullerene (1).

Significant differences of the proposed method:

1. The proposed method is based on the use of water as a starting reagent and catalyst Cp ₂ ZrCl ₂ . In the known method, boron hydride and alkaline hydrogen peroxide are used. The proposed method, unlike the known one, allows one to selectively introduce one hydroxyl fragment into the fullerene molecule to selectively produce 1-hydroxy-1,2-dihydro [60] fullerene (1).

The method is illustrated by the following examples:

EXAMPLE 1. 0.01 mmol of C60 fullerene, 6 ml of toluene, 55 mmol of water and 0.0020 mmol of Cp ₂ ZrCl ₂ catalyst are placed in a glass flask, stirred for 1 hour at a temperature of 80 ° C, 1-hydroxy-1,2-dihydro is obtained [60] fullerene with a yield of 88% (according to HPLC).

¹³ C NMR spectrum (δ, ppm) of 1-hydroxy-1,2-dihydro [60] fullerene (1).

52.97 (C ¹ ), 70.79 (C ² ). The signals of the carbon atoms of the fullerene fragment are located in the region 137-156.

Other examples confirming the method are given in table 1.

Table 1 №№ Molar ratio, C ₆₀ : H ₂ O: Cp ₂ ZrCl ₂ , mmol The reaction temperature, ° C Reaction time, hour Yield (1),% one 2 3 four 5 one. 0.01: 55: 0.002 80 one 88 2. 0.01: 65: 0.002 80 one 91 3. 0.01: 45: 0.002 80 one 77 four. 0.01: 55: 0.0025 80 one 94 5. 0.01: 55: 0.0015 80 one 72 6. 0.01: 55: 0.002 80 1.5 90 7. 0.01: 55: 0.002 80 0.5 75 8. 0.01: 55: 0.002 70 one 73 9. 0.01: 55: 0.002 90 one 92

Toluene was used as a solvent, since it has the highest solubility of fullerene C ₆₀ .

Claims (1)

The method of obtaining 1-hydroxy-1,2-dihydro [60] fullerene of the General formula (1)

characterized in that the fullerene C ₆₀ is reacted with water in the presence of a zirconacenedichloride catalyst in a molar ratio of C ₆₀ : H ₂ O: Cp ₂ ZiCl ₂ equal to 0.01: (45-65) :( 0.0015-0.0025) in toluene medium as a solvent at a temperature of 70-90 ° C for 0.5-1.5 hours