Prediction of Setschenow constants of N-heteroaromatics in NaCl solutions based on the partial charge on the heterocyclic nitrogen atom.
The solubilities of 19 different kinds of N-heteroaromatic compounds in aqueous solutions with different concentrations of NaCl were determined at 298.15 K with a UV-vis spectrophotometry and titration method, respectively. Setschenow constants, Ks, were employed to describe the solubility behavior, and it is found that the higher ring numbers of N-heteroaromatics gave rise to the lower values of Ks. Moreover, Ks showed a good linear relationship with the partial charge on the nitrogen atom (QN) for either QN > 0 or QN < 0 N-heteroaromatics. It further revealed that QN was well-matched in the prediction of salting-out effect for N-heteroaromatics compared to the conventional descriptors such as molar volume (VH) and the octanol-water partition coefficient (Kow). The heterocyclic N in N-heteroaromatics may interact with Na(+) ions in NaCl solution for QN < 0 and with Cl(-) for QN > 0.
Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
Bin
B
Yang
Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
Zhongjian
Z
Li
Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
Lecheng
L
Lei
Wanhua Chemical (Ningbo) Co. Ltd, Ningbo, 315000, China. feifeisun123@gmail.com.
Feifei
F
Sun
Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China. jingkezhu@zju.edu.cn.
Jingke
J
Zhu
D020003:1-Octanol / Q000737:chemistry; D006571:Heterocyclic Compounds / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry*; D012995:Solubility; D012996:Solutions; D014867:Water / Q000737:chemistry
D006571:Heterocyclic Compounds; D012996:Solutions; D014867:Water; D012965:Sodium Chloride; D009584:Nitrogen; D020003:1-Octanol
N-heteroaromatics; Partial charge; Salting-out effect; Setschenow constant; Solubility