Nitro compounds correlation table

The correlation tables for nitro compounds, nitroso compounds and nitrites are in Appendix 2, Table A2.10. 

Table 13-2. Spectral Correlations of Aromatic Nitro Compounds, Nitramines, and Nitrates...

The results from EFISH experiments are listed in Table IV along with the FF predictions. We note that the our measured values for 4-dimethylamino-4 -nitrostilbene (DANS) and 4-dimethylamino-4 -nitroazobenzene are consistent with previously published work (26,27). The theoretical predictions discussed previously show an excellent correlation with the actual measured values for (Mg)zPz. As predicted the nonlinearities of nitro-containing compounds are larger... 

The full AM1-SM2 model is discussed in more detail in the final section. Within the context of Tables 2-5, however, it is worth noting that the model enjoys the largest correlation to experimental data for the neutral solutes. All but a few of the molecules listed comprise a subset of a larger data set of 147 neutral solutes spanning many functionalities (e.g., nitro groups, phosphorus compounds, sulfides, bromides, fluoroalkanes, iodides, polyfunctional compounds), not shown because they have not been studied by other methods, for which the AM1-SM2 model has a mean absolute error of 0.6 kcal/mol.203 One apparent flaw illustrated here is that AM1-SM2 consistently underestimates the free energies of solvation for aliphatic and alicyclic ethers. 

The pKa values determined by Brand et aL (36) (corrected to the Paul and Long Ho scale in Table XVIII) do not correlate well with Hammett o- parameters as they should if their conjugate acids behaved in response to substitution as the isoelectronic carboxylic acids do. These authors attempted to explain the discrepancy in terms of solvation-entropy factors. However, if one employs Brown s or parameters (which were not available to the original workers cited above) one obtains a better correlation (5). Furthermore, one may note that if the pKa for p-nitrophenol (141) is included on the conjugate acids of the phenols (11) it is found to be far removed from the correlation line. One may conclude from this that p-nitrophenol protonates on the nitro, rather than on the hydroxy group. 

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