## 2 Materials and Methods
### Vaporization Thermodynamics of Alkyl-Quinolines and Alkyl-Pyridines
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Compound** & **M a** & **T-Range** & \(\Delta_{1}^{\rm g}H_{\rm m}^{\rm o}\) (\(T_{\rm av}\)) & \(\Delta_{1}^{\rm g}H_{\rm m}^{\rm o}\) (298.15 K) b  & **Ref.** \\ \hline
**CAS** & & **K** & **kJ\(\cdot\)mol\({}^{-1}\)** & **kJ\(\cdot\)mol\({}^{-1}\)** & \\ \hline
2-n-butyl-pyridine & SF & 340–465 & \(46.8\pm 1.6\) & \(54.3\pm 1.7\) & Table S4 \\
5058-19-5 & \(J_{x}\) & & & \(54.7\pm 1.0\) & Table 5 \\  & \(T_{b}\) & & & \(52.8\pm 1.5\) & Table 8 \\  & & & & **54.2 \(\pm\) 0.8 c ** & average \\ \hline
3-n-butyl-pyridine & SF & 347–482 & \(49.8\pm 2.0\) & \(58.2\pm 2.1\) & Table S4 \\
539-32-2 & \(J_{x}\) & & & \(56.1\pm 1.0\) & Table 5 \\  & \(T_{b}\) & & & \(55.3\pm 1.5\) & Table 8 \\  & & & & \(56.2\pm 0.8\) c  & average \\ \hline
4-n-butyl-pyridine & SF & 371–482 & \(48.9\pm 2.0\) & \(58.3\pm 2.1\) & Table S4 \\
5335-75-1 & \(J_{x}\) & & & \(55.4\pm 1.0\) & Table 5 \\  & \(T_{b}\) & & & \(55.5\pm 1.5\) & Table 8 \\  & & & \(55.8\pm 0.8\) c  & average \\ \hline \hline \end{tabular}  
* Techniques: E = ebuliometry; CC = Calvet microcalorimetry; n/a = method is not available; \(T\) = transpiration method; SF—from experimental boiling temperatures reported at different pressures compiled by SciFinder (11) (see text); \(J_{x}\)—from correlation of experimental vaporization enthalpies with retention indices (see text); \(T_{b}\)—from correlation of experimental vaporization enthalpies with normal boiling temperatures. b Uncertainties of the vaporization enthalpies are expressed as the expended uncertainty (0.95 level of confidence, k = 2). They include uncertainties from the experimental conditions uncertainties from adjustment of vaporization enthalpies to the reference temperature \(T\) = 298.15 K (7,8). c Weighted mean value (the uncertainty was taken as the weighing factor). Values in brackets were excluded by the averaging. Values highlighted in bold were recommended for thermochemical calculations.  
\end{table} 
Table 3: \(Cont.\)Validation of Vaporization Enthalpies, \(\Delta_{\mathrm{I}}^{\mathrm{g}}H_{\mathrm{m}}^{\mathrm{o}}\)(298.15 K), of Alkyl-Quinolines and Alkyl-Pyridines  
As can be seen from Tables 2 and 3, the vaporization enthalpies, \(\Delta_{\mathrm{I}}^{\mathrm{g}}H_{\mathrm{m}}^{\mathrm{o}}\)(298.15 K), derived from vapor pressures measured by the conventional methods, as well as those derived from the SciFinder [11] data, are in good agreement for all alkyl-quinolines and alkyl-pyridines compiled in these tables. This good agreement has increased the usefulness of extracting experimental boiling temperatures at various pressures compiled by SciFinder [11] for evaluating the scarce thermodynamic data. Nevertheless, taking into account the less accurate data from SciFinder, as well as the unexplainable outlying of the vaporization enthalpies derived for 2-methyl-quinoline and 4-methyl-quinoline directly by calorimetry [17], an additional validation of the \(\Delta_{\mathrm{I}}^{\mathrm{g}}H_{\mathrm{m}}^{\mathrm{o}}\)(298.15 K)-values evaluated in Tables 2 and 3 is required. This additional validation was conducted in this work using the available alkyl-quinolines and alkyl-pyridines chromatographic retention indices (Section 3.3.1), using correlation with the normal boiling temperatures (Section 3.3.2), using group-additivity principles (Section 3.3.3), and using the correlation with the chain length (Section 3.3.4).