Propionic anhydride is a colorless liquid. Melting point -45°C, boiling point 167°C, relative density 1.0125 (20/4°C), refractive index 1.4038, flash point 73°C. It is soluble in methanol, ethanol, ether, chloroform and alkali, and decomposes in water.

Uses

Propionic anhydride is used as a propionylating agent in the manufacture of medicines, fragrances and special esters. It is used in the pharmaceutical industry to produce Propionate (antibiotics), testosterone propionate (androgen deficiency), and propionic acid. Hydroxymethylandrosterone (anticancer drug), bemethasone (adrenal cortex hormones) and betamethasone dipropionate (adrenal cortex hormones), etc. In organic synthesis, it is also used as a dehydrating agent for nitration and sulfonation reactions, and used to make alkyd resins and dyes.

Synthetic Method

one atmosphere, 120°C, 3% propanol/air (propanol accounts for 3% of the total partial pressure of the reactant gas), volumetric space velocity is 40/h, the catalyst is a supported Pd catalyst Pd/Zr02, Pd and ZrO2 The mass ratio is 10:100, and the results show that propanol is partially converted into propionic anhydride, the conversion rate of propanol is 100%, the selectivity of acid anhydride is 55%, and the yield of propionic anhydride is 55%.