Table 1.

Kinetic Parameters for Activation of OMPDC by Oxydianions and Derived Parameters for Dianion Binding to OMPDC and to [E•EO]^‡ (Scheme 4).^a

Oxydianion	Kd/Mb	(kcat/Km)E•X M−1 s−1 b	Kd‡/M c	RTln(Kd‡) kcal/mol d
HPO32− e	0.14	1600	2.3 × 10−6	−7.7
HOPO32−	0.025	0.11	5.9 × 10−3	−3.0
SO32−	0.027	920	7.6 × 10−7	−8.3
SO42−	0.055	3.1	4.6 × 10−4	−4.5
S2O32−	0.014	0.87	4.2 × 10−4	−4.6
HOAsO32−	No detectable activation

^aFor reactions at pH 7.1, 25 °C and I = 0.14 (NaCl) unless noted otherwise.

^bExperimental kinetic parameter defined by Scheme 3.

^cDisassociation constant for release of the oxydianion from the transition state complex, calculation using eq 3 derived for Scheme 4.

^dThe intrinsic dianion binding energy.

^eRef 8.