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The influence of O 2 and H 2 O on the formation of iron dithiolates (IDTs) by the reactions of thiols and organic disulfides with the iron powder was studied under the static (without mechanical activation of the reaction) and dynamic (with mechanical activation of the reac tion) conditions. Under the static conditions in the absence of O 2 or H 2 O, only BnSH and PhSH give IDTs, whereas DdSH (Dd is dodecyl) produces IDTs in the presence of O 2 or H 2 O. For the mechanical activation of the reactions of organic disulfides with the iron powder, the formation of IDTs is possible if the reaction mixture contains H 2 O. On the interaction with iron oxides excess thiols are oxidized to organic disulfides and also afford IDTs.Organic disulfides are widely used as additives de creasing friction and frictional wear of steel surfaces. In this case, disulfides partially decompose to thiols under boundary friction conditions. 1 Mechanochemical reac tions occurring via the reactions of organic disulfides and thiols with iron favor continuous service of steel mecha nisms. However, chemical methods for analysis of prod ucts of mechanochemical reactions have not been devel oped up to recently. We have previously 2 proposed the method for studying mechanochemical reactions with the help of a mechanochemical vibrational mill. It has been shown 2 that, contrary to the popular opinion, 3,4 IDTs appear from thiols rather than from organic disul fides.The purpose of the present work is to study the influ ence of O 2 and H 2 O on the formation of IDTs by the reactions of thiols and organic disulfides with the iron powder under the static and dynamic conditions. Results and DiscussionThe following reactions were studied:where R = Pr (a), Bu (b), Dd (dodecyl, c), Bn (d), and Ph (e).The influence of O 2 in the reaction medium was stud ied in the processes involving thiols 1b-e, and the effect of an H 2 O admixture was examined in the reactions of thiol 1c and disulfide 3a. The results are presented in Table 1.Static conditions. Some IDTs are formed without mechanochemical activation of the reactions of thiols with the iron powder. For instance, the formation of IDTs 2b,d,e was visually observed by the appearance of the color several minutes or hours after mixing the reactants. When IDTs 2d,e were formed, hydrogen bubbles evolved for several weeks. In the first case, in several months a black product with metallic luster formed instead of brown IDT 2d, whereas red brown IDT 2e did not change its color. If the reaction mixture is sealed in an air atmo sphere, thiols 1b-e initially turned to green. The brown color characteristic of IDTs appears in several days.In the absence of O 2 , thiol 1c with the iron powder forms no IDT 2c. No changes on the iron surface were visually observed even after many year contact of the re actants in an evacuated ampule. However, if the ampule containing thiol 1c and the iron powder was sealed off under atmospheric pressure without degassing, then the brown color characteristic of IDTs appears already in 30-6...