RU2349593C1 - Method of producing 2,3-fullero-7-thiabicyclo [2,2,1]heptane - 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 electronic, magnetic and optical properties. The essence of the method lies in reaction of fullerene C₆₀ with thiophane in the presence of a Cp₂HfCl₂ catalyst in a toluene medium at 140-160°C temperature for 5-7 hours.

EFFECT: design of a method of selective production of 2,3-fullero-7-thiabicyclo[2,2,1]heptane with 47-70% output of target product.

9 ex, 1 tbl

Description

The present invention relates to organic chemistry, specifically to a method for producing 2,3-fullero-7-thiabicyclo [2.2.1] heptane 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 specified electronic, magnetic and optical properties.

A known method ([1], N. Jagerovic, J. Elguero, J.-L. Aubagnac. Tetrahedron, 1996, 52, 6733-6738) for producing an azidofulleroid of formula (2) with a 25% yield by thermal reaction of C ₆₀ with azidobenzothiazole in solution o-dichlorobenzene for 7 days.

The known method does not allow to obtain 2,3-fullero-7-thiabicyclo [2.2.1] heptane (1).

A known method ([2], H. Ishida, K. Itoh, M.Ohno. Tetrahrdron, 2001, 57.1737-1747) for preparing fullerotetrahydrothiophene of formula (3) by the reaction of addition of bis (trimethylsilylmethyl) sulfoxide to C ₆₀ in o-dichlorobenzene at a temperature of 110 ° C according to the scheme:

The known method does not allow to obtain 2,3-fullero-7-thiabicyclo [2.2.1] heptane (1).

Thus, in the literature there is no information on the selective synthesis of 2,3-fullero-7-thiabicyclo [2.2.1] heptane (1).

A new method is proposed for producing 2,3-fullero-7-thiabicyclo [2.2.1] heptane of the general formula (1).

The essence of the method consists in the interaction of fullerene C ₆₀ with thiophan in the presence of a hafnacenedichloride catalyst (Cp ₂ HfCl ₂ ), taken in a molar ratio respectively 0.01: (0.045-0.055) :( 0.0015-0.0025), preferably 0.01: 0.05: 0.0020, at 140 -160 ° C for 5-7 hours in a toluene solution. The yield of 2,3-fullero-7-thiabicyclo [2.2.1] heptane (1) is (according to HPLC) 47-70%. The reaction proceeds according to the scheme:

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

2,3-Fullero-7-thiabicyclo [2.2.1] heptane (1) is formed only with the participation of fullerene [60] and thiophan.

Carrying out this reaction in the presence of a catalyst of hafnacenedichloride Cp ₂ HfCl ₂ more than 0.0025 mol does not significantly increase the yield of the target product (1). The use of a catalyst of the hafnacenedichloride Ср ₂ HfCl ₂ catalyst less than 0.0015 mol reduces the yield of the product (1), which is possibly associated with a decrease in catalytically active sites in the reaction mass.

A change in the ratio of the starting reagents towards a significant increase in the thiophan content with respect to fullerene [60] leads to the addition of additional molecules of the starting cyclic sulfide to the C ₆₀ molecule.

Significant differences of the proposed method:

1. The proposed method is based on the use of thiophan and a catalyst Cp ₂ HfCl ₂ as a starting reagent. In the known method, bis (trimethylsilylmethyl) sulfoxide is used. The proposed method, unlike the known one, allows one to selectively obtain 2,3-fullero-7-thiabicyclo [2.2.1] heptane (1), the synthesis of which is not described in the literature.

The method is illustrated by the following examples.

Example 1. In a metal autoclave with a volume of 17 ml, 0.01 mmol of fullerene C ₆₀ , 10 ml of “dry” toluene, 0.05 mmol of thiophan and 0.002 mmol of catalyst Cp ₂ HfCl _{2 are} placed, stirred for 6 hours at a temperature of 150 ° C., 2,3-fullero is obtained -7-thiabicyclo [2.2.1] heptane of the general formula (1) with a yield of 64% (according to HPLC).

¹³ C NMR spectrum of 2,3-fullero-7-thiabicyclo [2.2.1] heptane (1) (δ, ppm):

34.87 (С^5,6), 67.38 (С^1,4), 75.11 (С^2,3).

34.87 (C ^5.6 ), 67.38 (C ^1.4 ), 75.11 (C ^2.3 ).

The signals of the carbon atoms of the fullerene fragment are located in the region of 128-156 ppm.

Other examples confirming the method are given in table 1.

Table 1 №№ Molar ratio, C ₆₀ : (CH ₂ ) ₄ S: Cp ₂ TiCl ₂ , mmol The reaction temperature, ° C Reaction time, hour Yield (1),% one 2 3 four 5 one. 0.01: 0.05: 0.002 150 6 64 2. 0.01: 0.055: 0.002 150 6 67 3. 0.01: 0.045: 0.002 150 6 58 four. 0.01: 0.05: 0.0025 150 6 70 5. 0.01: 0.05: 0.0015 150 6 47 6. 0.01: 0.05: 0.002 140 6 53 7. 0.01: 0.05: 0.002 160 6 68 8. 0.01: 0.05: 0.002 150 7 66 9. 0.01: 0.05: 0.002 150 5 57

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

Claims (1)

The method of obtaining 2,3-fullero-7-thiabicyclo [2.2.1] heptane of the General formula (1)

characterized in that the fullerene C ₆₀ interacts with thiophan in the presence of a hafnacenedichloride catalyst in a molar ratio of C ₆₀ : thiophan: Cp ₂ HfCl ₂ = 0.01: (0.045-0.055) :( 0.0015-0.0025) in toluene at a temperature of 140-160 ° C for 5-7 hours