Table 5.

Rate and Equilibrium Constants for Carbon Deprotonation of Glycine and Glycine Derivatives in Water at 25 °C and I = 1.0 (KCl)

Carbon Acid	kHOa (M−1s−1)	pKab	Carbon Acid	kHOa (M−1s−1)	pKab
	4.5 × 10−5 c	28.9c		4.1c	21.0c
	3.3 × 10−4 c	27.3c		390c	18.0c
	2.9	21.9		9.0 × 103 d	14d
	2.0 × 10−4	27		ca. 1	ca. 23
	0.13	25		1.1 × 104 d	14d
	not determined	ca. 23 e		7.5 × 102 f	17f

^aSecond-order rate constant for deprotonation of the carbon acid by hydroxide ion calculated from data reported in this work, unless noted otherwise.

^bpK_a for ionization of the carbon acid in water calculated from data reported in this work, unless noted otherwise.

^cData from ref 2.

^dData from ref 28.

^eEstimated as described in the text.

^fData from ref 29.