RU2348601C1 - Method of obtaining polyhydro[60]fullerenes - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention concerns method of obtaining polyhydro[60]fullerenes of formula (1):

, involving fullerene C₆₀ interaction with diisobutylaluminum chloride (i-Bu₂AlCl) in the presence of zirconocene dichloride catalyst (Cp₂ZrCl₂) at molar ratio of C₆₀:i-Bu₂AlCl:Cp₂ZrCl₂=1:(55-65):(0.15-0.25), preferably 1:60:0.20, in argon atmosphere in the absence of light at room temperature of 60-100°C and atmospheric pressure in toluene medium for 1-5 hours, with further hydrolysis of reaction mass. The method allows obtaining total 77-91% output of polyhydro[60]fullerene after reaction mass hydrolysis.

EFFECT: improved method.

1 tbl, 7 ex

Description

The present invention relates to the field of organic chemistry, specifically, to a method for producing polyhydro [60] fullerenes of the general formula (I):

Polyhydro [60] fullerenes of the formula (1) can be used in fine organic synthesis, in the production of high-energy fuels, and hydrogen batteries.

The known method ([1], AGAvent, ADDarwish, DKHeimbach, HWKroto, MFMeidine, JPParsons, C. Remars, R. Roers, O. Ohashi, R. Taylor, DRMWalton. J. Chem. Soc. Perkin Trans. 2, 1994, 15) obtaining dihydro [60] fullerene (2) by reacting a benzene solution [60] fullerene with an excess of hydrazine hydrate (~ 1: 1000) in the presence of glacial acetic acid, copper sulfate and sodium periodate with vigorous stirring ~ 20 hours in an argon atmosphere.

Polyhydro [60] fullerenes of the formula (1) cannot be obtained in a known manner.

A known method ([2], S. Ballenweg, R. Gleiter, W. Kratschmer. J. Chem. Soc., Chem. Commun., 1994, 2269) for the preparation of polyhydro [60] fullerenes (4) by hydrocyrronization of C ₆₀ with zirconacenchloride hydride (Schwartz reagent) at a temperature of 20-22 ° C in a toluene solution for 24 hours, followed by hydrolysis of the zirconium-fullerene complexes formed in situ (3) according to the scheme:

Polyhydro [60] fullerenes of the formula (1) with the number of hydrogen atoms from 6 to 12 on the fullerene sphere can be obtained in a known manner.

A new method for producing polyhydro [60] fullerenes of the formula (1) is proposed.

The essence of the method consists in the interaction of fullerene C ₆₀ with diisobutylaluminium chloride (i-Bu ₂ AlCl) in the presence of catalytic amounts of Cp ₂ ZrCl ₂ taken in a molar ratio of C ₆₀ : i-Bu ₂ AlCl: Cp ₂ ZrCl ₂ = 1: (55-65 ) :( 0.15-0.25), preferably 1: 60: 0.20, in an argon atmosphere in the absence of light at a temperature of 60-100 ° C and atmospheric pressure in toluene for 1-5 hours, followed by hydrolysis of the reaction mass. The total yield of polyhydro [60] fullerenes of the formula (1) is 77-91%.

The reaction proceeds according to the scheme:

Carrying out this reaction in the presence of a catalyst Cp ₂ ZrCl ₂ more than 0.25 mol does not lead to a significant increase in the yield of the target product (1). The use of the catalyst Cp ₂ ZrCl ₂ less than 0.15 mol reduces the yield of the target product (1), which is probably associated with a decrease in catalytically active centers in the reaction mass. The reaction was carried out at a temperature of 60-100 ° C. At a higher temperature (for example, 120 ° C), there is no significant increase in the yield of the target product (1), and at a lower temperature (for example, 20 ° C), the reaction rate decreases. A change in the ratio of the starting reagents in the direction of increasing their content with respect to the starting fullerene [60] does not lead to a significant increase in the yield of the target product (1).

Significant differences of the proposed method:

In the known method, the inaccessible Schwartz reagent (Cp ₂ ZrClH) is used as the starting compound, and in the proposed method, commercially available i-Bu ₂ AlCl is used as the starting compound.

The proposed method, in contrast to the known, allows to obtain polyhydro [60] fullerenes of the formula (1).

The method is illustrated by the following examples:

EXAMPLE 1. In a glass reactor mounted on a magnetic stirrer, in an argon atmosphere, 40 ml of dried toluene, 0.05 mmol C ₆₀ , 0.01 mmol of catalyst Cp ₂ ZrCl ₂ and 3 mmol of i-Bu ₂ AlCl are placed, stirred for 3 hours in the absence of light at a temperature 80 ° C. The reaction mixture was treated under argon in the absence of light with an ethereal HCl solution, passed through Al ₂ O ₃ , and the solvent was evaporated in vacuo. Polyhydro [60] fullerenes (1) are obtained with a yield of 83%.

Spectral characteristics of polyhydro [60] fullerenes (1):

IR spectrum (υ, cm ^-1 ): 2925, 2855.

¹ H NMR Spectrum (δ, ppm, CDCl ₃ ): 3.57, 4.90, 5.75, 5.84, 6.26, 6.43, 6.65, 7.06 ppm.

M ⁺ : 722 [C ₆₀ H ₂ ], 738 [C ₆₀ H ₁₈ ].

Other examples confirming the method are shown in table 1.

Table 1 №№ The ratio of C ₆₀ : i-Bu ₂ AlCl: Cp ₂ ZrCl ₂ , mmol The reaction temperature, ° C Reaction time, h The output of polyhydro [60] fullerenes (1),% one. 1: 60: 0.2 80 3 83 2. 1: 65: 0.2 80 3 86 3. 1: 55: 0.2 80 3 80 four. 1: 60: 0.25 80 3 91 5. 1: 60: 0.15 80 3 77 6. 1: 60: 0.2 80 5 89 7. 1: 60: 0.2 80 one 78 1: 60: 0.2 one hundred 3 85 1: 60: 0.2 60 3 78

The reactions were carried out at a temperature of 60-100 ° C in toluene in an argon atmosphere without access of light.

Claims (1)

The method of obtaining polyhydro [60] fullerenes of the formula (I)

characterized in that the fullerene C ₆₀ is reacted with diisobutylaluminium chloride (i-Bu ₂ AlCl) in the presence of a catalyst of zirconacene dichloride (Cp ₂ ZrCl ₂ ) taken in a molar ratio of C ₆₀ : i-Bu ₂ AlCl: Cp ₂ ZrCl ₂ = 1 :( 55-65) :( 0.15-0.25), preferably 1: 60: 0.20, in an argon atmosphere in the absence of light at a temperature of 60-100 ° C and atmospheric pressure in toluene for 1-5 hours subsequent hydrolysis of the reaction mass.