The chemistry of Lawessons reagent and related substances has been reviewed by several times. The main use of Lawessons reagent is the thionation of carbonyl compounds. For instance, Lawessons reagent will convert a carbonyl into a thiocarbonyl. Additionally, Lawessons reagent has been used to thionate enones, esters, lactones, amides, lactams, and quinones.
In one study, reaction of maltol with LR results in a selective oxygen replacement in two positions.
A combination of silver perchlorate and Lawesson's reagent is able to act as an oxophilic Lewis acid with the ability to catalyze the Diels–Alder reaction of dienes with α,β-unsaturated aldehydes.
in some cases, alcohols may be converted to thiols by treatment with Lawesson's reagent.
Lawesson's reagent reacts with sulfoxides to form thioethers.