Preparation of hexafluoroisopropanol_Industrial additives

Background and overview^[1]

Hexafluoroisopropanol (1,1,1,3,3,3-hexafluoro-2-propanol, abbreviated as HFIP) is used as an intermediate for pharmaceuticals and agricultural chemicals, as a solvent or in electronic devices detergent in , and used in analytical applications due to its ability to dissolve a wide range of polymers. HFIP exhibits strong hydrogen bonding and will bind and dissolve most molecules with accepting sites such as oxygen, double bonds, or amine groups. Forms stable distillable complexes with many ethers or amines due to strong hydrogen bonds. HFIP is soluble in water and most organic solvents. It is a volatile (boiling point 58.2°C) and polar substance with high density, low viscosity and low surface tension. HFIP is transparent to UV light and has a low refractive index.

Hexafluoroisopropanol is an excellent solvent that can dissolve many insoluble polymers at room temperature, including nylon-66, nylon-6, polyamide, polyester, polyacrylonitrile, polycondensate Aldehydes and hydrolyzed polyethylene esters, etc. This important property of hexafluoroisopropyl alcohol can be used in the recycling of plastics; and in the chromatographic analysis of polymers, it can form a useful polymer coating on the surfaces of many objects. Hexafluoroisopropyl alcohol also has excellent surface tension, which can disperse and dissolve certain dyes and organic pigments well, allowing them to easily enter some porous structural materials, such as metals, ceramics, concrete, and textile fibers, making these materials Easily stained. Hexafluoroisopropanol is also an important intermediate for preparing anesthetics. The anesthetics prepared with it have low clinical dosage, are easily absorbed by the human body, have high anesthetic efficiency and have little impact on the human body.

Preparation^[2]

Into a jacketed 316L stainless steel reactor with an inner diameter of 50mm and a length of 1500mm, add 1350 grams of hexafluoroacetone trihydrate, 13.5 grams of palladium carbon catalyst with 5% (weight) palladium content, and 3.4 grams of sodium hydroxide. After repeated substitution of hydrogen, after the oxygen content is qualified, the temperature is raised to 120°C, the reaction pressure is adjusted to 1.0MPa by adding hydrogen, and the reaction begins.

After the reaction reaches a pressure of 0.9MPa, gas phase hexafluoroacetone and hydrogen (volume ratio 80:20) are mixed in a static mixer and then pressurized, and added to the reactor, maintaining a constant pressure of 1.0MPa, and react for 14 hours , stop adding hexafluoroacetone. After another 2 hours, the pressure drop almost no longer occurs. Cool to room temperature, drain and discharge. Filter to obtain 3040 grams of liquid phase material. Packed column chromatography analysis showed that the hexafluoroisopropanol content was 89%, the water content was about 10.5%, and the rest were impurities.

References

[1][China invention, China invention authorization] CN200980121726.8 Continuous method for preparing hexafluoroisopropanol

[2][Chinese invention] CN200710042071.8 Semi-continuous preparation method of hexafluoroisopropanol