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. Author manuscript; available in PMC: 2019 Nov 28.
Published in final edited form as: Chem Rev. 2018 Oct 29;118(22):10840–11022. doi: 10.1021/acs.chemrev.8b00074

Table 4.

Comparison of CO and O2 Bimolecular Rates and Binding Constants for Select (Ligand)copper(I) Complexes, Hemocyanins (Hc), and Selected Hemesa

graphic file with name nihms-1001466-t0213.jpg
compound or protein (solvent) KCO (M−1) KO2 (M−1) kCO (M−1 s−1) kO2 (M−1 s−1) k−CO (s−1) k−O2 (s−1)
NMe2LCuI (THF) 4.9 × 103 100 2.5 × 109 2.3 × 1011 5.0 × 105 2.3 × 109
ImLCuI (THF) 2.4 × 103 17.4 2.8 × 109 3.4 × 1010 1.1 × 106 1.9 × 109
(TMPA)CuI (THF) 1.2 × 104 15.4 1.9 × 109 1.3 × 109 1.6 × 105 1.3 × 108
(TMPA)CuI (EtCN) 220 0.38 5.9 × 107 5.8 × 107 2.7 × 105 1.5 × 108
(tBuTMPA)CuI (THF)c 1.7 1.6 × 108 9 × 107
(TMPA)CuI (EtCN) 15.5 1.2 × 107
(PV-TMPA)CuI (MeTHF) 4.8 × 107
(TMG3tren)CuI (MeTHF) ~ 1 2.7 × 107 1.5 × 107
(LiPr)CuI (THF)d 6.3 5.9 × 102 1.5 × 106
Cyt aa3 oxidase (CuB)e 7 × 103 3.5 × 108 5 × 104
Cyt bo3 oxidase (cyt o3)f 3.8 × 107
Tt ba3g 1 × 109
myoglobin (human) 2.6 × 107 (0.74–117) × 104 7.6 × 105 (1.4–25) × 107 0.022 22
hemoglobin (human) 4.6 × 108 (2.9–48) × 105 4.6 × 106 (2.9–22) × 107 0.009 13.1
FeII-porphyrinatesh 105 – 106 106 – 108
Limulus Hc (arthropod) (2.7–11.2) × 103 (2.6–5.4) × 105 (2–4.3) × 105 (1.3–1.9) × 106 38–75 2.4–7.5
Busycon Hc (mollusk) 220 × 103 1.8 × 105 7.7 × 105 (1.1–2.2) × 106 3–4 6.5–11.5
a

Values correspond to 298 K, and for synthetic copper complexes, they have been extrapolated to this temperature from cryogenic measurements. See the following citations and references cited therein.691,940,977,1002,1003 Also see sections 2 and 3 in this review for further discussions regarding many of the synthetic complexes mentioned in this table.

b

MeTHF = 2-methyl tetrahydrofuran.

c

A TMPA ligand with 4-substituted (t-butyl) pyridyl donors.691

d

Extrapolated to 298 K from data in reference.1004

e

Bovine enzyme. Further transfer of O2 to heme a3 occurs with kO2 = 5 × 104 s−1.976,979

f

Binding to the o3 heme, E. coli bo3 ubiquinol oxidase.1005

g

Binding to the heme of reduced Tt ba3.912,990

h

Includes hemes such as picket fence, pocket, durene capped, chelated proto- or meso-, deutero- or tetraphenyl- porphyrin.