RU2594561C2 - Method of producing n-alkil aziridino[2',3':1,9] fullerene [60] - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to organic chemistry, more specifically to method of producing N-alkyl aziridinium fullerenes of general formula (1), where R = Me, Et, i-Pr, Bu, which can be used as complexing agents, sorbents, biologically active compounds, as well as when producing novel materials with given properties. According to suggested method fullerene C₆₀ interacts with linear azides RN₃ (R = Me, Et, i-Pr, Bu) in presence of ytterbium triflate Yb(OTf)₃ in molar ratio C₆₀:RN₃:Yb(OTf)₃ = 1:(0.5-2):(0.5-2) and room temperature (~20 °C) in chlorobenzene for 18-30 hours.

EFFECT: method enables to obtain N-alkyl aziridinium fullerenes of formula (1) with high output and selectivity.

1 cl, 1 tbl

Description

The present invention relates to the field of organic synthesis, and in particular to a method for producing N-alkylaziridinofullerenes of the general formula (1):

Aziridinofullerenes with various functional groups and substituents can be used as donor-acceptor systems that simulate photosynthesis, convert sunlight to electrical energy, generate reactive oxygen species, capture radicals (antioxidants), exhibit semi- and superconducting properties, and also ferromagnetism. (IP Romanova “Electron-withdrawing mono- and bis-cycloadducts of fullerene C _60. Synthesis, structure and properties.” Thesis for the degree of Doctor of Chemical Sciences. Kazan, 2008 [1]).

A known method (Romanova IP “Electron-withdrawing mono- and bis-cycloducts of fullerene C _60. Synthesis, structure and properties.” The dissertation for the degree of Doctor of Chemical Sciences. Kazan, 2008 [1]) to obtain a mixture of aziridinofullerene (2) and azagomofullerene (3) with a total yield of 30% and a ratio of 1: 5, respectively, by the reaction of fullerene C ₆₀ (4) with diphenyl azide phosphate in 1,2-dichlorobenzene at 130 ° C for 3 hours.

The known method does not allow to selectively obtain N-alkylaziridino [2 ′, 3 ′: 1,9] fullerenes [60] of the general formula (1).

The known method (Liu, F .; Du, W .; Liang, Q .; Wang, Y .; Zhang, J .; Zhao, J .; Zhu, S. Tetrahedron 2010, 66, 5467-5471 [2]) for the preparation of aziridinofullerene (5) with a yield of ~ 60%, the interaction of fullerene C ₆₀ (4) with 1,8-nafilimide azide in boiling 1,2-dichlorobenzene or under microwave radiation (MVI), which turned out to be more effective.

The disadvantage of this method is the need for boiling the reaction mixture in 1,2-dichlorobenzene (180 ° C), which leads to high energy consumption.

A new method is proposed for producing N-alkylaziridino [2 ′, 3 ′: 1.9] fullerenes [60] (1).

The essence of the method consists in the interaction of fullerene C ₆₀ (4) with linear azides RN ₃ (where R = Me, Et, i-Pr, Bu) in the presence of ytterbium triflate Yb (OTf) ₃ , taken in a molar ratio of C ₆₀ : RN ₃ : Yb (OTf) ₃ = 1: (0.5-2) :( 0.5-2), preferably 1: 1: 1, in a solution of chlorobenzene at room temperature (~ 20 ° C), for 18-30 hours. N- alkylaziridino [2 ′, 3 ′: 1.9] fullerenes [60] (1) with a yield of 33-48%. The reaction proceeds according to the scheme:

The starting azide is taken in an equimolar amount with respect to fullerene C ₆₀ in order to selectively produce the monoadduct (1) in high yield. A decrease in the amount of azide with respect to C _{60 is} impractical, since it leads to a decrease in yield (1). Carrying out this reaction in the presence of ytterbium triflate [Yb (OTf) ₃ ] more than 100 mol% with respect to fullerene C ₆₀ does not lead to a significant increase in the yield of the target product (1). The use of a heterogeneous catalyst [Yb (OTf) ₃ ] in an amount of less than 100 mol% with respect to fullerene C ₆₀ reduces the yield of the target product, which is associated with a decrease in reaction centers. The reaction must be carried out at room temperature. Carrying out the reaction at a higher temperature is associated with an increase in energy consumption, as well as an increase in the number of formed products of the polyaddition of azide to C ₆₀ .

Significant differences of the proposed method.

The proposed method is based on the use of linear azides as a starting reagent, as well as the use of stoichiometric amounts of ytterbium triflate catalyst [Yb (OTf) ₃ ]. The proposed method, unlike the known ones, allows one to obtain individual N-alkylaziridino [2 ′, 3 ′: 1,9] fullerenes (1) with high selectivity and yields.

The method is illustrated by examples.

In a two-neck glass reactor was dissolved 40 mg (0.055 mmol) of ₆₀ C in 8 mL of dry chlorobenzene was added with vigorous stirring (0.055 mmol) of an organic azide and Yb (OTf) _{March 20} mg (0.055 mmol). After the reaction mass was stirred for 24 hours. After a lapse of time, the reaction mass was passed through a small layer of silica gel. The reaction products and fullerene C ₆₀ were separated using semi-preparative HPLC, eluent-toluene. As a result, N-alkylaziridino [2 ′, 3 ′: 1.9] fullerenes [60] of the general formula (1) were obtained with a yield of 33-47%.

Spectral characteristics (1)

Other examples confirming the method are given in table. one

Claims (1)

The method of obtaining N-alkylaziridinofullerenes of the General formula (1)

,
where R = Me, Et, i-Pr, Bu, characterized in that the fullerene C ₆₀ interacts with linear azides RN ₃ (where R = Me, Et, i-Pr, Bu) in the presence of ytterbium triflate Yb (OTf) ₃ , taken in a molar ratio of C ₆₀ : RN ₃ : Yb (OTf) ₃ = 1: (0.5-2) :( 0.5-2), at room temperature (~ 20 ° C) in chlorobenzene for 18-30 hours.