CS245149B1 - Method of 2,2,3,4,4,4-hexafluobutanol production - Google Patents

Abstract

The purpose of the invention is to prepare 2,2,3,4,4,4-hexafluorobutanol, which serves as a special solvent for polyamides, applies in the preparation of materials for optoelectronics, microelectronics and fabric treatment. The substance is produced according to the invention by reacting hexafluoropropene with methanol ultraviolet radiation initiation. Production is carried out under pressure in a photochemical reactor 0.1 to 0.8 MPa and at -50 to 80 ° C.

Description

The purpose of the invention is the preparation of 2,2,3,4,4,4-hexafluorobutanol, which serves as a special solvent for polyamides, used in the preparation of materials for optoelectronics, microelectronics and fabric treatment.

According to the invention, the substance is produced by reacting hexafluoropropene with methanol under initiation by ultraviolet radiation. The production is carried out in a photochemical reactor at a pressure of 0.1 to 0.8 MPa and at temperatures of -50 to 80 ° C.

The present invention relates to a process for the preparation of 2,2,3,4,4,4-hexafluorobutanol of general formula (I)

CF 3 - CHF - CF 2 - CH 2 OH by reaction of hexafluoropropene with methanol under initiation by ultraviolet radiation.

Fluorinated alkanols are prepared by a variety of synthetic procedures and methods. From the point of view of the last synthetic step, substitution, addition and reduction reactions are used in the synthesis of these compounds. Conversions of terminal polyfluoroalkyl iodides to the corresponding primary fluorinated alcohols have been used in the substitution reactions.

Addition reactions include several types. These include the addition of fluorinated or non-fluorinated organometallic reagents to non-fluorinated or fluorinated aldehydes resulting in the formation of primary and especially secondary fluorinated alcohols. Furthermore, it is the addition of formaldehyde to fluorinated alkenes in hydrogen fluoride environment or with catalysis of alkali metal fluorides. Finally, it is the addition of alkanols to fluorinated alkenes to form primary, secondary and tertiary fluorinated alkanols.

Reductions also include several methods. By catalytic reduction of fluorinated ketones, secondary alcohols are obtained, catalytic reduction of perfluorocarboxylic acids gives corresponding primary fluorinated alkanols. Reductions of the functional acid derivatives which are carried out with various complex hydrides also provide the corresponding alkanols, while the functional dicarboxylic acid derivatives yielded the corresponding fluorinated diols.

The preparation of 2,2,3,4,4,4-hexafluorobutanol by addition of methanol to hexafluoropropene is also reported in the literature. The addition is caused by the thermal decomposition of the radical initiators, so it is necessary to work at elevated temperature and elevated pressure.

The disadvantages of the prior art are eliminated by the process for the preparation of 2,2,3,4,4,4-hexafluorobutanol of the general formula:

1CF 3 - CHF - CF 2 - CH 2 OH by reaction of hexafluoropropene with methanol under initiation by ultraviolet radiation. The process according to the invention consists in carrying out the reaction in a photochemical reactor at a pressure of 0.1 to 0.8 MPa at a temperature of -70 to 70 ° C. In the reaction, hexafluoropropene is fed to the reactor. The reaction time depends on the reactor volume and the amount of methanol present in the reactor, pressure and reaction temperature. The light source in the quartz shell is either fully immersed in the liquid phase or only partially, or with a small amount of alcohol, the source can be placed above the liquid phase inside the reactor. Additive ultraviolet radiation is emitted, for example, by a mercury and xenon lamp.

The process of the invention has a number of advantages. The reaction can be carried out extensively. The volume and reaction rate or rate can be easily controlled. Reaction temperature and relatively small pressure changes allow for further speed control. The process according to the invention is described by way of example.

Example 1

Perfluoropropene was introduced at a temperature of 50 ° C and a pressure of 0.2 MPa to a 400 ml submersible photochemical reactor containing 300 g of methanol at a rate sufficient to react. The radiation source was a 150 W ultraviolet lamp. A total of 77 g of hexafluoropropene was added over 12 hours. The reaction mixture was then subjected to rectification ranging from 112 to 114 ^{° C} C, 53.3 g of 2,2,3,4,4,4-hexafluorobutanol containing 4.5 mol% were obtained. isomeric hexafluoro-isobutyl alcohol.

Example 2

350 g of methanol were charged to a 500 ml submerged photochemical reactor, then the reactor was cooled to -60 ° C and 110 g of hexafluoropropene was added. The source of activation radiation was a 400 W ultraviolet lamp. The reaction mixture was warmed to -40 ^° C and reacted at this temperature and pressure of 0.12 MPa for 12 hours. The reaction mixture was then rectified to obtain 89.5 g of 2,2,3,4,4,4-hexafluorobutanol containing 2.1% / mole at 112-114 ° C. isomeric hexafluoro-isobutyl alcohol.

The hexafluorobutanol prepared according to the invention has a number of uses. For example, it serves as a special solvent for polyamides and is used in the preparation of fabric treatment materials, microelectronics and optoelectronics.

Claims (1)

SUBJECT A process for the preparation of 2,2,3,4,4,4-hexafluorobutanol of general formula 1CF 3 - CHF - CF 2 - CH 2 OH by the reaction of hexafluoropropene with methanol (YNALEZU), characterized in that the reaction is carried out with the initiation by ultraviolet radiation in a photochemical reactor at a pressure of 0.1 to 0.8 MPa at temperatures of -50 to 80 ° C,