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. Author manuscript; available in PMC: 2022 Jun 8.
Published in final edited form as: Chem Rev. 2021 Dec 20;122(1):1–49. doi: 10.1021/acs.chemrev.1c00521

Table 24.

PCET thermochemistry of 4d/5d-based transition metal systems.a

compound (ML–H) solvent E∘(Mn–L)0/− E∘(Mn–LH)+/0 pKa(Mn+1LH) pKa(Mn–LH) E∘(V vs H2) BDFE
[(bpy)2pyRuIIOH2]2+ H2O   0.4695    1.0295  0.8595   10.395   1.07 77.5
trans-[RuIV(tmc)(O)(OH2)]2+b H2O   0.80416    --  --   4.7416   1.08 77.7
trans-[RuV(tmc)(O)(OH)]2+b H2O   0.56416    [>0.67]  <1.0416   2.8416   0.73 69.5
[[(bpy)2pyRuIIIOH]2+ H2O   <0.48100    >1.6100  <0.0100   >13.0100   1.15 79.3
(Me6cyclam)Rh(HO)(OOH)2+c H2O   --    --  --   --   0.950 74.7389
(Me6cyclam)Rh(H2O)(OOH)2+c H2O   --    --  --   --   0.970 75.2389
(dipic)RuII(tpyCO2H)d MeCN   0.047417    --  --   18.5417   1.170 79.0
(dipic)RuII(tpyPhCO2H)d MeCN   0.1787    --  --   20.587   1.41 84.6
(acac)2RuII(pyImH)e MeCN   −1.0082    −0.6482  16.082   [22.1]   0.34 59.7
(hfacac)2RuII(pyImH)e MeCN   –0.0782    0.2982  [13.2]   19.382   1.10 77.4
[RuII(dmdmp)Cl(MeBPA)]f MeCN   −0.16418    0.14418  [11.4]   16.4418   0.84 71.3
[RuII(dmdmp)(TPA)]+f MeCN   0.26419    0.52419  [9.9]   14.3419   1.14 78.2
TpOsIII(NH2Ph)Cl2g MeCN   −1.05420    0.48420  [−3.3]420   22.5420   0.31 59.1
[SNS]Pd(PPh3)h MeCN   −0.58408    --  --   17.4408   0.48 63.0
[SNS]Pt(PPh3)h MeCN   –0.51408    --  --   22.2408   0.83 71.2
TpMo(CO)3Hg MeCN   –0.521421    --  --   10.7421   0.140 55.2
Tp′Mo(CO)3Hi MeCN   −0.59422    --  --   10.2422   0.04 53.0
TpW(CO)3Hg MeCN   −0.582421    --  --   14.4421   0.298 58.9
(Phtpy)(PPh2Me)2MoNH3j THF   −1.09195    --  --   3.6195    −0.53 39.7
(Phtpy)(PPh2Me)2MoCH2CH3j THF   −1.35423    --  --   16.3423    −0.04 51.0
(teriPrP2)Mo2PHk THF   −0.52424    --  --   3.6423   0.04 52.8
a

Potentials for 1e− reductions are in V vs SHE if in aqueous solution and V vs Cp2Fe+/0 if they are in organic solution. Values for E∘(V vs H2) are in V; – eE∘ is the average free energy for 12H2(g) addition. Uncited values of E∘(V vs H2) were calculated from other values in the row using Scheme 2 or eq 18. BDFEs are in kcal mol−1 and if uncited were calculated from E∘(V vs H2) using eq 18. Values in [square brackets] have been calculated from the other values in the row using Hess′ law.

b

tmc = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane.

c

Me6cyclam = Me6cyclam = meso-hexamethylcyclam.

d

dipic = dipicolinic acid; tpyCO2H = 2,2′:6,2″-terpyridine-4’-carboxylic acid; tpyPhCO2H = 2,2′:6,2″-terpyridine-4′-benzoic acid.

e

acac = acetylacetonate; hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate; pyimH = 2-(1H-imidazol-2-yl)pyridine.

f

dmdmp = N,N-dimethyl-6,7-dimethylpterin; TPA = tris(2-pyridylmethyl)amine; MeBPA = N-methyl-N,N-bis(pyridylmethyl)amine.

g

Tp = hydrotris(1-pyrazolyl)borate.

h

[SNS]H3 = bis(2-mercapto-p-tolyl)amine.

i

Tp′ = hydrotris(3,5-dimethylpyrazolyl)borate.

j

Phtpy = 4′-phenyl-2,2′:6,2″-terpyridine.

k

teriPrP2 = 1,4-bis(2-(diisopropylphosphino)phenyl)benzene.