Thionyl chloride (CAS No 7719-09-7)

Abstract

Thionyl chloride is a colorless liquid (sometimes pale yellow due to impurities), molecular weight 118.97, boiling point 76 °C, soluble in carbon tetrachloride, benzene and chloroform, density 1.631 g.cm-3 and smell resembling that of sulfur dioxide (SO2). This reagent is highly versatile and is used in several synthetic methodologies to obtain several intermediaries and chemicals of interest in agrochemistry, fine chemistry and pharmacy. The industrial production of thionyl chloride is expensive and specific facilities are required to contain and handle the reagents, products and impurities in an eco-friendly manner. Several methodologies of production of this reagent are described and most of them use sulfur oxides. Thionyl chloride must be carefully handled, because this reagent can cause irritation and severe burns to eyes, membranes and skin.