Theoretical calculation pKa values of phthalhydrazide derivatives in its aqueous solutions

Resumo

The pK_a values of some phthalhydrazide derivatives were calculated using ab initio and two density functional methods to obtain information about their reaction conditions. The results showed that pK_a1 was influenced by structural modification as it varied between 0.47 and 6.99, and that pK_a2 was relatively less variable from 16.66 to 21.53. The high values of pK_a2 revealed that a strong alkaline solution was necessary for all chemiluminescent reactions of discussed phthalhydrazide derivatives.