Thioacyl chloride explained

In organic chemistry, thioacyl chloride is a functional group of the type RC(S)Cl, where R is an organic substituent. Thioacyl chlorides are analogous to acid chlorides, but much rarer and less robust. The best studied is thiobenzoyl chloride, a purple oil first prepared by chlorination of dithiobenzoic acid with a combination of chlorine and thionyl chloride.^{[1] [2]} A more modern preparation employs phosgene as the chlorinating agent,^[3] this also generates carbonyl sulfide as a by-product.

PhCS₂H + COCl₂ → PhC(S)Cl + HCl + COSThe most common thioacyl chloride is thiophosgene.

References

1. Thiobenzoyl chloride. Ueber Thiobenzoylchlorid. . Siegwart, J. . Helvetica Chimica Acta. 1920. 3. 824–833 . 10.1002/hlca.19200030177.
2. Book: Acyl Halides . Saul Patai. 1972. 10.1002/9780470771273.ch11 . PATAI'S Chemistry of Functional Groups. Thiocarbonyl halides . Potts KT, Sapino C . 349–380 . 9780470771273 .
3. 10.1002/zfch.19750150904 . Viola H, Mayer R. Z. Chem.. Eine neue Darstellungsmethode für aromatische Thiocarbonsäurechloride. A New Preparation Route for Aromatic Thiocarboxylic Acid Chlorides. 1975. 15. 9 . 348.