Bomzon Biswadeep, Khunger Yashita, Subramanian Ranga
Department of Chemistry, Indian Institute of Technology Patna 801106 India
RSC Adv. 2020 Jan 13;10(4):2389-2395. doi: 10.1039/c9ra08392h. eCollection 2020 Jan 8.
The basic ionization (p ) and acidic ionization (p ) constants and equilibrium constant ( ) of 2HPy and 2MPy were determined. The p (s) of their - and -methyl derivatives (X = O, S) were also determined. The equilibrium constant of 2MPy is approximately 60 times greater than its oxygen analog, 2HPy. The micro-ionization constants of the functional groups, -NH (p and p ) and -XH (p and p ), were determined to provide further insights into the ionization equilibria of these N-heteroaromatic XH compounds (2HPy and 2MPy). The relaxation time of water () in aqueous solutions of 2HPy and 2MPy are collectively used with the values to determine the forward ( ) and backward ( ) rate constants of tautomerization. Subsequently, the and are used to provide the rationale for the and values.
测定了2-羟基吡啶（2HPy）和2-巯基吡啶（2MPy）的基本电离常数（p ）、酸电离常数（p ）和平衡常数（ ）。还测定了它们的α-和β-甲基衍生物（X = O，S）的p （s）。2-巯基吡啶的平衡常数约为其氧类似物2-羟基吡啶的60倍。测定了官能团-NH（p 和p ）和-XH（p 和p ）的微电离常数，以进一步深入了解这些N-杂芳基XH化合物（2-羟基吡啶和2-巯基吡啶）的电离平衡。2-羟基吡啶和2-巯基吡啶水溶液中水的弛豫时间（ ）与 值一起用于确定互变异构的正向（ ）和反向（ ）速率常数。随后， 和 用于解释 和 值的合理性。
