A composition comprises the reaction product of a dithiophosphate derivative and an amine. The reaction product is present in the composition in an amount of at least about 25 wt. %. The composition may include additional components. A method of forming the composition comprises the step of combining the dithiophosphate derivative and the amine to form the composition. A method of increasing thermal stability of a dithiophosphate derivative comprises the step of combining the dithiophosphate derivative and an amine. The dithiophosphate derivative can decompose to form hydrogen sulfide (H2S). However, the amine substantially prevents thermal decomposition of the dithiophosphate derivative. An example of the dithiophosphate derivative is 3-(di-isobutoxy-thiophosphorylsulfanyl)-2-methyl-propanoic acid. An example of the amine is ditridecyl amine. The composition can be used for a variety of applications. For example, the composition can be used as an antiwear compound/additive in lubricants, metalworking fluids, hydraulic fluids, etc.