RU2238929C1 - Method for preparing 1-[3'-hydroxy-3'-alkyl-(3',3'-dialkyl)]-n-propyl-2-hydro[60]fullerenes - Google Patents

Abstract

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing 1-[3'-hydroxy-3'-alkyl-(3',3'-dialkyl)]-n-propyl-2-hydrp[60]fullerenes of the general formula (1):

wherein if R means hydrogen atom (H) then R' means n-C₃H₇, n-C₅H₁₁; if R means CH₃ then R' means CH₃, C₂H₅; n = 1-3. Fullerene-containing alcohols and their derivatives can be used in fine organic synthesis, in manufacturing medicinal preparation and biologically active substance. Method involves interaction of fullerene-C₆₀ with triethylaluminium (AlEt₃) in the mole ratio C₆₀ : AlEt₃ = 1:(25-35) in the presence of zirconacene dichloride (Cp₂ZrCl₂) as a catalyst taken in the amount 15-25 mole% with respect to C₆₀, in argon atmosphere, at room temperature (20-21^oC), under atmosphere pressure, in toluene medium followed by addition of copper chloride (CuCl) as a catalyst in the amount 15-25 mole% with respect to C₆₀ and aldehyde or ketone (RCOR') in the equimole amount with respect to AlEt₃ to reaction mass at temperature -15^oC. Then reaction mass is stirred at room temperature followed by hydrolysis of reaction mass.

EFFECT: improved preparing method.

1 tbl, 10 ex

Description

The present invention relates to organic chemistry, specifically to a method for producing 1- [3'-hydroxy-3'-alkyl (3 ', 3'-dialkyl)] - n-propyl-2-hydro [60] fullerenes of the general formula (1 ):

where R = H, R '= n-C ₃ H ₇ ;

R = H, R '= n-C ₅ H ₁₁ ;

R = CH ₃ , R = CH ₃ ,

R = CH ₃ , R '= C ₂ H ₅ ; n = 1-3

Fullerene-containing alcohols and their derivatives can be used in fine organic synthesis, in the production of drugs, biologically active substances.

The known method ([1]. Fyles TM, Leznoff CC, Weatherston J. The use of polymer supports in organic synthesis. XII. The total stereoselective synthesis of cis insect sex attractants on solid phase. Can. J. Chem., 1977, v 55, No. 23, pp. 4135-4143) for the preparation of unsaturated alcohols of the general formula (2) by hydroboration of alkin-1-tins with 9-borabicyclo [3.3.1] nonane (9-BBN) followed by hydrolysis of the reaction mixture with acetic acid according to the scheme

In a known manner, fullerene-containing alcohols of the general formula (1) cannot be obtained.

The known method ([2]. Schneider NS, Darwish AD, Kroto HW, Taylor R., Walton DRM Formation of Fullerols via Hydroboration of Fullerene-C _60. J. Chem. Soc. Chem. Commun., 1994, pp. 463- 464) obtaining fullerene-containing alcohols of the general formula (3) by hydroboration of fullerene C ₆₀ with boron hydride (BH ₃ ) followed by oxidation of the reaction mass with alkaline hydrogen peroxide according to the scheme

The known method does not allow to obtain fullerene-containing alcohols of the general formula (1).

A new method is proposed for the preparation of 1- [3’-hydroxy-3’-alkyl (3 ’, 3’-dialkyl)] - n-propyl-2-hydro [60] fullerenes of the general formula (1).

The essence of the method consists in the interaction of fullerene C ₆₀ with triethylaluminum (AlEt ₃ ), taken in a molar ratio of C ₆₀ : AlEl ₃ = 1: (25-35), preferably 1:30, in the presence of a catalyst of zirconacenedichloride (Cp ₂ ZrCl ₂ ) in an amount 15-25 mol.% In relation to C ₆₀ , preferably 20 mol.%, In an argon atmosphere at room temperature (20-21 ° C) and atmospheric pressure in a toluene solution for 8 hours, followed by addition to the reaction mass at a temperature -15 ° C of a catalyst for copper chloride (CuCl) in an amount of 15-25 mol.% In relation to the initial fullerene C ₆₀ and aldehyde or ketone (RCOR ') in a quantity equivalent to AlEt ₃ , followed by stirring of the reaction mixture at room temperature (20-21 ° C) for 6-10 hours, preferably 8 hours. The total yield of 1- [3'-hydroxy-3'-alkyl (3 ', 3'-dialkyl)] - n-propyl-2-hydro [60] fullerenes of the general formula (1) is 65-87%.

The reaction proceeds according to the scheme.

R = H, R '= n-C ₃ H ₇ ; R = H, R '= n-C ₅ H ₁₁ ;

R = CH ₃ , R '= CH ₃ ; R = CH ₃ , R '= C ₂ H ₅

Fullerene-containing alcohols of the general formula (1) are formed only with the participation of AlEt ₃ , C ₆₀ and a zirconium catalyst Cp ₂ ZrCl ₂ . In the presence of other aluminum compounds (e.g. Bu $\genfrac{}{}{0ex}{}{\text{i}}{\text{2}}$ AlCl, Bu $\genfrac{}{}{0ex}{}{\text{i}}{\text{3}}$ Al, Bu $\genfrac{}{}{0ex}{}{\text{i}}{\text{2}}$ AlH, EtAlCl ₂ , Et ₂ AlCl) or other catalysts (e.g. Zr (acac) ₄ , ZrCl ₄ , Cp ₂ TiCl ₂ , Pd (acac) ₂ , Ni (acac) ₂ , NiCl ₂ , Fe (acac) ₂ ) target products (1) are not formed.

Carrying out this reaction in the presence of a catalyst Cp ₂ ZrCl ₂ or CuCl more than 25 mol.% With respect to fullerene [60] does not lead to a significant increase in the yield of target products (1). The use of catalysts Cp ₂ ZrCl ₂ or CuCl less than 15 mol.% Reduces the yield of the target products (1), which is possibly associated with a decrease in catalytically active centers in the reaction mass. The reactions were carried out at room temperature (20-21 ° C). At a higher temperature (for example, 40 ° C), there is no significant increase in the yield of the target products (1), and at a lower temperature (for example, 0 ° C), the reaction rate decreases.

A change in the ratio of the starting reagents in the direction of increasing their AlEt ₃ content with respect to the starting fullerene C ₆₀ does not significantly increase the yield of the target products (1).

Reactions were carried out using toluene as a solvent. In other solvents (for example, aliphatic, halogenated, ethereal), the solubility of the original C ₆₀ decreases.

Significant differences of the proposed method

In the proposed method, AlEt ₃ , aldehydes, ketones are used as starting compounds, and the reaction is catalyzed by Cp ₂ ZrCl ₂ and CuCl. In the known method, boron hydride (BH ₃ ) and alkaline hydrogen peroxide (H ₂ O ₂ / NaOH) are used as starting reagents.

The proposed method, unlike the known one, allows to obtain 1- [3'-hydroxy-3'-alkyl (3 ', 3'-dialkyl)] - n-propyl-2-hydro [60] -fullerenes of the general formula (1), synthesis which are not described in the literature. The method is illustrated by the following examples:

EXAMPLE 1. In a 100 ml glass reactor mounted on a magnetic stirrer in an argon atmosphere, 45 ml of dry toluene, 0.04 mmol C ₆₀ , at a temperature of ~ 0 ° C 1.20 mmol AlEt _{3 were} placed, stirred for 8 hours at room temperature (20-21 ° C), then at a temperature of -15 ° C, add 0.008 mmol of a CuCl catalyst and 1.20 mmol of oil aldehyde, stir for 8 hours at a temperature of 20-21 ° C, the reaction mass is hydrolyzed with an ether solution of Hcl. 1- [3'-hydroxy-3'-alkyl (3 ', 3'-dialkyl)] - n-propyl-2-hydro [60] fullerene of the general formula (1) is isolated from the organic layer in a yield of 77%.

Spectral characteristics of 1- [3’-hydroxy-3 ’- (n-propyl)] (n-propyl) -2-hydro [60] fullerene of the general formula (I)

IR spectrum (v, cm ^-1 ): 3400, 3350, 2950, 2860, 1725, 1690, 1580, 1510, 1460, 1370, 1165, 1100, 1030, 730. ¹ H NMR spectrum (δ, ppm) ): 2.11 (2H at C ¹ ), 1.39 (6H at C ² , C ⁴ , C ⁵ ), 3.38-3.99 (1H at C ³ ), 0.87 (3H at C ⁶ ), 6.40 (1H at C ⁸ )

¹³ C NMR spectrum (δ, ppm): 34.57 (C ¹ ), 28.78 (C ² ), 65.78 (C ³ ), 29.17 (C ⁴ ), 22.74 (C ⁵ ), 14.04 (C ⁶ ), 48.59 (C ⁷ ), 53.14 (C ⁸ ). The signals of the carbon atoms of the fullerene fragment are located in the region of 140.70-155.79 ppm. Other examples confirming the method are given in the table.

The reactions were carried out at room temperature (20-21 ° C) in a solution of toluene in an argon atmosphere without access of light. In all experiments, the number of hydroxyalkyl substituents in the fullerene molecule [60] varies from 1 to 3.

Claims (1)

The method of obtaining 1- [3'-hydroxy-3'-alkyl (3 ', 3'-dialkyl)] - n-propyl-2-hydro [60] fullerenes of the General formula (1)

where if R = H, then R '= n-C ₃ H ₇ , n-C ₅ H ₁₁ ; if R = CH ₃ , then R ^' = CH ₃ , C ₂ H ₅ ; n is 1-3; characterized in that the fullerene C ₆₀ is reacted with triethylaluminium (AlEt ₃ ) in a molar ratio of C ₆₀ : AlEt ₃ = 1: (25h35) in the presence of a catalyst of zirconacenedichloride (Cp ₂ ZrCl ₂ ) taken in an amount of 15-25 mol% by relative to C ₆₀ , in an argon atmosphere at room temperature of 20-21 ° C and atmospheric pressure in toluene, followed by addition of a catalyst of copper chloride (CuCl) in the amount of 15-25 mol.% to the reaction mass at a temperature of -15 ° C in relation to to C ₆₀ and aldehyde or ketone (RCOR ') in an amount equimolar to AlEl ₃ , after which the reaction mass is stirred at room temperature, followed by hydrolysis of the reaction mass.