Oxyacids of sulfur and their anhydrides

Mechanisms and Reactivity in Reactions of Organic Oxyacids of Sulfur and their Anhydrides... 

Mechanism and reactivity in reactions of organic oxyacids of sulfur and their anhydrides, 17, 65... 

Orotidine monophosphate decarboxylase, the mechanism of, 38, 183 Oxyacids of sulfur and their anhydrides, mechanisms and reactivity in reactions of organic, 17, 65 Oxygen isotope exchange reactions of organic compounds, 3, 123... 

Among the oxyacids of sulfur the predilection to form an anhydride with a sulfur-sulfur bond, rather than one with an oxygen bridge between the two sulfurs, is not restricted to sulfenic acids. We will see in a subsequent section that sulfinic acids also do this. Their anhydrides have the sulfinyl sulfone structure. RS(0)S02R, rather than RS(0)0S(0)R. What is unique about the sulfenic acid-thiolsulfinate system, however, is the fact that the anhydride (thiolsulfinate) is strongly preferred thermodynamically over the acid at equilibrium. With any other type of common acid the reverse is true, of course. The uniqueness of the sulfenic acid-thiolsulfinate situation can perhaps best be appreciated by realizing that, if the same stability relationship between acid and anhydride were to exist for carboxylic acids, acetic acid would spontaneously dehydrate to acetic anhydride ... 

To keep this review to a reasonable length we had to limit our discussions to reactions of only sulfur oxyacids and their anhydrides. While we have introduced, where pertinent to the topic under discussion, results from a number of studies involving other derivatives of oxyacids of sulfur, there has been extensive work on mechanism and reactivity in reactions of some sulfur oxyacid derivatives that we have not been able to include, but of which we feel the reader should at least be aware. We will therefore indicate briefly what some of these areas are and given some leading references, so that persons wishing to do so may explore these topics on their own. 

The support of the Robert A. Welch Foundation (Grant D-650), which has made possible our continued investigation of, and interest in, mechanisms and reactivity in reactions of sulfur oxyacids and their anhydrides, is gratefully acknowledged. 

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