The reactions of carbon disulfide and sulfur dioxide with small carboxylate anions

Abstract

In one form or another both acid gases and carboxylates have existed from prebiotic earth all the way to the present day. Here we have studied the reactions of carbon disulfide (CS[subscript 2]) and sulfur dioxide (SO[subscript 2]) with naked carboxylate anions (RCOO[superscript -]) to observe the types of interactions possible. The reaction of CS[subscript 2] with acetate (CH[subscript 3]COO[superscript -]) in acetonitrile under an inert atmosphere proceeded via an exchange mechanism. This produced carbonyl sulfide gas (COS) and a thioacetate salt, which was characterized by X-ray crystallography. On the other hand, under the same conditions, the reaction of SO[subscript 2] with formate (HCOO[superscript -]) created a radical sulfur species. Overall, this led to the isolation of H[subscript 2] and CO[subscript 2] gases and to the formation of a number of possible SxOyn- species. Both reactions are thermodynamically stable enough to occur when salts of the anions, with large, non-coordinating cations, are exposed to the acid gases. The variety and biological importance of the products produced in these simple reactions show that their study may still hold many interesting and important new findings.