RU2747026C1 - Method for producing bis(2,2,3,3,4,4,5,5-octafluoropentyloxy)methane - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: present invention relates to a method for producing bis(2,2,3,3,4,4,5,5-octafluoropentyloxy)methane, which can be used as a heat carrier, a solvent for conducting reactions, a component of chemical compositions for the formation of electrolytes of chemical current sources and lubricants, as well as an alkylating reagent. The method consists in the fact that 2,2,3,3,4,4,5,5-octafluoropentanol-1 is first treated with a paraformaldehyde at a molar ratio (1,8-2) : 1 in the presence of toluene sulfonic acid and o-xylene or p-xylene, followed by fractionation of the mixture at atmospheric pressure and with the distillation of bis(2,2,3,3,4,4,5,5-octafluoropentyloxy)methane at reduced pressure.

EFFECT: proposed invention makes it possible to obtain the target product in a simple and effective way using minimal amounts of commercially available reagents.

1 cl, 3 ex

Description

The invention relates to the field of organic chemistry, namely, to a method for producing bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane, which can be used as a heat carrier, a solvent for carrying out reactions, as a component chemical compositions for the formation of electrolytes, chemical current sources and lubricants, and also as an alkylating reagent.

A known method of producing bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane by interaction of pentakis (2,2,3,3,4,4,5,5-octafluoropentyloxy) phosphorane with paraform in autoclave at 200 ° C for 9 h, followed by rectification of the mixture (Journal of General Chemistry (1982), 52 (11), 2526-2531). A previously synthesized phosphorane is used as a starting compound. Conversion and yield values for bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane, which is a by-product, are not indicated. The disadvantages of this method include the need to synthesize the starting compound by the interaction of phosphorus pentachloride and 2,2,3,3,4,4,5,5-octafluoropentanol-1, the use of an autoclave and heating to a high temperature for a long time.

A known method of producing bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane by interaction of 2,2,3,3,4,4,5,5-octafluoropentanol-1 with 5-7 molar excess paraform, followed by rectification of the mixture in vacuum on a Simex microcolumn (Journal of Organic Chemistry (1990), 26 (6), 1187-1191). The time and other conditions of the reaction, the conversion and yield of bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane are not indicated. The disadvantages of this method include the need to use an excess amount of paraform and rectification on a microcolumn.

A known method of obtaining - a close analogue - a homologue of bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane - bis (2,2,3,3-tetrafluoropropyloxy) methane (US 3526667). The reaction of interaction of paraform and 2,2,3,3-tetrafluoropropanol-1 at a molar ratio of paraforms: 2,2,3,3-tetrafluoropropanol-1 = 1: 18 is carried out in 96% sulfuric acid at 0 ° C for 2 hours. The product is isolated by diluting the reaction mixture with a large amount of water and subsequent extraction with ether. Bis (2,2,3,3-tetrafluoropropyloxy) methane is obtained by distillation under reduced pressure. The yield was 63.4%. Another method for producing bis (2,2,3,3-tetrafluoropropyloxy) methane uses the reaction of interaction between paraform and 2,2,3,3-tetrafluoropropanol-1 at a molar ratio of paraforms: 2,2,3,3-tetrafluoropropanol-1 = 1 : 2.14 in methylene chloride in the presence of concentrated sulfuric acid at 0 ° C for 2 hours. The product is isolated by additional extraction of the sulfuric acid layer with methylene chloride, followed by washing with water, sodium bicarbonate solution and again with water. Bis (2,2,3,3-tetrafluoropropyloxy) methane was isolated by distillation under reduced pressure, yield not reported. Significant disadvantages of the methods are the need for synthesis with cooling to 0 ° C, the need to use an excess amount of 2,2,3,3-tetrafluoropropanol-1 and a large amount of organic solvents, water and aqueous solutions for product extraction.

The objective of the invention is to obtain bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane in a simple and effective way using minimal amounts of commercially available reagents.

The problem is solved by the fact that in the method for producing bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane 2,2,3,3,4,4,5,5-octafluoropentanol-1, first treated with paraform at a molar ratio of (1.8 - 2): 1 in the presence of toluenesulfonic acid and o-xylene or p-xylene, followed by fractionation of the mixture at atmospheric pressure and distillation of bis (2,2,3,3,4,4,5 , 5-octafluoropentyloxy) methane under reduced pressure. The reactions are carried out in a standard manner in a direct condenser distillation apparatus at atmospheric pressure. Fractionation of the mixture was carried out using a standard distillation apparatus with direct condenser under reduced pressure. The recommended conditions for the production of bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane have been established empirically, and are also determined by the concepts of the process outlined below. To obtain bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane, commercially available 2,2,3,3,4,4,5,5-octafluoropentanol-1 and paraform are used. The use of a molar ratio of 2,2,3,3,4,4,5,5-octafluoropentanol-1: paraforms above 2: 1 leads to excessive and ineffective consumption of reagents. The use of a molar ratio of 2,2,3,3,4,4,5,5-octafluoropentanol-1: paraform below 1.8: 1 is ineffective due to the low conversion of reagents. The initial fractionation of the mixture must be carried out at atmospheric pressure using a reflux condenser, which ensures efficient separation of the components. The separation of bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane must be carried out under reduced pressure to prevent decomposition

Analysis of the composition and structure of bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane was carried out using elemental analysis (elemental analyzer "PE 2400", Perkin Elmer), infrared Fourier spectroscopy (spectrometer "Nicolet 6700 ", Thermo scientific) and nuclear magnetic resonance spectroscopy (spectrometer" AVANCE 500 ", Bruker).

The preparation of bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane is illustrated by the following examples:

Example 1

A mixture of 27.84 ml (0.2 mol) of 2,2,3,3,4,4,5,5-octafluoropentanol-1, 3.2 g (0.11 mol) paraform and 0.2 g of p-tolulsulfonic acid in 3.6 ml of o-xylene was boiled under a direct condenser, distilling off the first fraction at atmospheric pressure, and the second fraction at reduced pressure (165 ° C / 20 mm Hg). Yield 39.96 g (84%), n = 1.326 (n_litas= 1.325). Found,%: C 27.23; H 1.95; F 63.80. For formula C_elevenH_eightF_sixteenO₂ calculated,%: C 27.73; H 1.68; F 63.87. NMR spectrum^oneН, СDСl₃, ppm: 4.08 (m, 4H, J = 13.9 Hz, OCH₂CF₂), 4.85 (m, 2H, J = 10.6 Hz OCH₂O), 6.05 (t.q, 2H, J^one= 6.1 Hz, J²= 52.0 Hz НСF₂). NMR spectrum^nineteenF, СDСl₃, ppm: 24.52 (m, 2F, J_CF= 52.0 Hz), 31.60 (m, 2F, J_CF = 46.0 Hz), 36.15 (m, 1F, J_CF = 8.5 Hz), 36.36 (m, 1F, J_CF = 30.74 Hz ), 39.3 (m, 1F, J_CF = 10.98 Hz), 41.6 (m, 1F, J_CF = 10.92 Hz). IR spectrum, cm^-one: 3416, 2969, 1169, 1130, 979, 809.

Example 2

A mixture of 33.4 ml (0.24 mol) of 2,2,3,3,4,4,5,5-octafluoropentanol-1, 3.6 g (0.12 mol) paraform and 0.24 g of p-tolulsulfonic acid in 4.3 ml of o-xylene was boiled with a direct condenser, distilling off the first fraction at atmospheric pressure, and the second fraction at reduced pressure (165 ° C / 20 mm Hg). Yield 51.9 g (91%).

Example 3

A mixture of 45.94 ml (0.33 mol) of 2,2,3,3,4,4,5,5-octafluoropentanol-1, 5.2 g (0.17 mol) paraform and 0.33 g of p-tolulsulfonic acid in 5.94 ml of p-xylene was boiled with a direct condenser, distilling off the first fraction at atmospheric pressure, and the second fraction at reduced pressure (165 ° C / 20 mm Hg). Yield 57.3 g (73%).

The method of obtaining is simple to implement. It uses commercially available compounds, the method allows you to exclude the preliminary synthesis of starting materials, does not require complex equipment and additional auxiliary devices. A significant advantage of the proposed method for producing bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane is the simplicity and manufacturability of the production process with fewer stages and auxiliary operations and a higher yield, in contrast to the known methods. The inventive method makes it possible to obtain bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane on any industrial reactor equipment without additional improvements. An additional advantage of the proposed method is the possibility. Bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane can be used in its intended form as a solvent for carrying out reactions, as a component of chemical compositions, including for the formation of electrolytes of chemical current sources, as well as as an alkylating reagent.

Claims (1)

A method for producing bis (2,2,3,3,4,4,5,5-octafluoropentyloxy) methane, characterized in that 2,2,3,3,4,4,5,5-octafluoropentanol-1 is first treated with paraform at a molar ratio of (1.8 - 2): 1 in the presence of toluenesulfonic acid and o-xylene or p-xylene, followed by fractionation of the mixture at atmospheric pressure and distillation of bis (2,2,3,3,4,4,5,5 -octafluoropentyloxy) methane under reduced pressure.