Sulfur- and chlorine-containing products are obtained by reacting C-10 alpha -olefins with sulfur monochloride. By sulfidation of the resulting reaction mixture with saturated aqueous sodium sulfide solution sulfur-containing products are synthesized. The optimum conditions are determined for synthesis of these products, which can be recommended as additives that improve tribological properties of lubricants. It is shown that specimens of mineral oils prepared by using the synthesized additives correspond in key performance properties to transmission oils TM-4, SAE, 80W-90, and API-type oil GL-4 with improved anti-scoring properties.