Carbon acidity of the α-pyridinium carbon of a pyridoxamine analog

被引：17

作者：

Crugeiras, J

Rios, A

Amyes, TL

Richard, JP ^{[1
]}

机构：

[1] Univ Santiago, Fac Quim, Dept Quim Fis, Santiago De Compostela 15706, Spain

[2] SUNY Buffalo, Univ Buffalo, Dept Chem, Buffalo, NY 14260 USA

来源：

ORGANIC & BIOMOLECULAR CHEMISTRY | 2005年 / 3卷 / 11期

关键词：

D O I：

10.1039/b504399a

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

We report second- order rate constants of k(DO) = 120 dm(3) mol(-1) s(-1) and k(B) = 6.4 x 10(-4) dm(3) mol(-1) s(-1) for exchange for deuterium of the first alpha-methylene proton of the 4-(aminomethyl) pyridine dication in D2O at 25. C and I = 1.0 (KCl). These data are consistent with a carbon acid pK(a) between 17 and 19 for ionization of this simple carbon acid and they show that the effect of an alpha-pyridinium substituent on carbon acidity is similar to that of an alpha-ester substituent.

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页码：2145 / 2149

页数：5

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