Answers are grounded in this paper and cite their sources.
The sulfonation of naphthalene in concentrated aqueous sulfuric acid has been reinvestigated. Rate measurements have been made in the region of 79.0‐83.4 wt‐% H2SO4 at 25°. The kinetically determined isomer distribution has been determined in the acid range of 75.5‐95.2 wt‐% H2SO4. At 25°, the ratio of 1‐ to 2‐naphthalenesulfonic acid decreases from 5.9 to 4.1 on varying the acid concentration from 75 to 95 wt‐% H2SO4. The higher reactivity of the 1‐ as compared with the 2‐position of naphthalene is largely due to the difference in enthalpy of activation, for the difference in entropy of activation is very small. The partial rate factors for sulfonation at the 1‐ and 2‐ positions decrease with increasing acid concentration. The ratio of the logarithms of these partial rate factors is 1.60 ± 0.03. The ratio of the rate constants of sulfonation of 1‐ and 2‐naphthalenesulfonic acid at 25° is ∼ 0.08. The partial rate factors for the most reactive positions of these acids have been compared with those for meta‐substitution of benzenesulfonic acid.
No takes yet. Share an insight, caveat, or question.
Cerfontain et al. (1967) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: