Thermochemistry of sulphonic acids

Liebman JF (1991) Thermochemistry of sulphonic acids and their derivatives. In Patai S, Rappoport Z (eds) The chemistry of the sulphonic acids, esters and their derivatives. Wiley, Chichester, p 283... 

We now proceed through with our commentary on the thermochemistry of other sulphonic acids and their derivatives. Although we began our literature search with 1941 so as to cover the 50 years before the publication of this volume, the earliest relevant reference is from 1944. In it18, Roth and Rist-Schumacher determined the heat of combustion, AHc (at constant pressure), of n-dodecane-1-sulphonic acid (18) to be 1868.0 3.7 kcal mol-1. These authors related this quantity to the heat of reaction of 69 4 kcal mol-1 that would be liberated by the hypothetical reaction 7... 

The reader will have noted that some unanswered questions were left in some of our earlier sections. For example, recall Reference 34 cited in Section V. A we did not evaluate on which side the equilibrium for reaction 54 lies. Because we subsequently considered the thermochemistry of sulphonyl sulphenates, we can now provide a partial, but admittedly long-winded, answer for the Ar = Ph species (46). The reader is reminded that A Hf(g, 46) — 52 kcal mol 1 and of the finding of Turecek and coworkers34 that the heat of formation of gaseous benzenesulphenic acid (84) is —8 kcal mol-1. Likewise, the reader may recall from Section VII.D our estimation for solid benzenesulphonic acid that AH (s, 20) = — 117 kcal mol- L These data cannot be immediately combined because of the discrepancy in the state for which the three species other than H20 are known. Do we wish to consider condensed phase species, in which case we need the sublimation energy of the sulphonyl sulphenate 46 and the sulphenic acid 84, or to consider gas phase species, in which case we need the sublimation energy of the sulphonic acid 20 ... 

For individuals interested in the energetics of sulphinic acids and their derivatives, we refer the reader to B. Bujnicki, M. Miko lajczyk and J. Omenlanczuk, Thermochemistry and thermolysis of sulphinic acid derivatives , in The Chemistry of Sulphinic Acids, Esters and their Derivatives (Ed. S. Patai), Wiley, Chichester, 1989. The comprehensive comparison of the interplay of structure and energetics of sulphinic and sulphonic acid (and, oh yes, sulphenic acid) derivatives is still unwritten and no doubt awaits a chapter in a yet-to-be-organized Supplement volume. 

---