Synergistic Activation of Nitrite and Thiocarbonyl Compounds Affords NO and Sulfane Sulfur via (Per)thionitrite (SNO<sup>−</sup>/SSNO<sup>−</sup>)
Gayathri Kolliyedath, Tuhin Sahana, Silpa Mary Johnson, Subrata Kundu
Abstract
Abstract (Per)thionitrite (SNO − /SSNO − ) intermediates play vital roles in modulating nitric oxide (NO) and hydrogen sulfide (H 2 S) dependent bio‐signalling processes. Whilst the previous preparations of such intermediates involved reactive H 2 S/HS − or sulfane sulfur (S 0 ) species, the present report reveals that relatively stable thiocarbonyl compounds (such as carbon disulfide (CS 2 ), thiocarbamate, thioacetic acid, and thioacetate) react with nitrite anion to yield SNO − /SSNO − . For instance, the reaction of CS 2 and nitrite anion (NO 2 − ) under ambient condition affords CO 2 and SNO − /SSNO − . A detailed investigation involving UV/Vis, FTIR, HRMS, and multinuclear NMR studies confirm the formation of SNO − /SSNO − , which are proposed to form through an initial nucleophilic attack by nitrite anion followed by a transnitrosation step. Notably, reactions of CS 2 and nitrite in the presence of thiol RSH show the formation of organic polysulfides R‐S n ‐R, thereby illustrating that the thiocarbonyls are capable of influencing the pool of bioavailable sulfane sulfurs. Furthermore, the availability of both NO 2 − and thiocarbonyl motifs in the biological context hints at their synergistic metal‐free activations leading to the generation of NO gas and various reactive sulfur species via SNO − /SSNO − .