Supporting Information. Aqueous Ferryl(IV) Ion. Kinetics of Oxygen Atom Transfer to Substrates, and Oxo. Exchange with Solvent Water

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1 Supporting Information Aqueous Ferryl(IV) Ion. Kinetics of Oxygen Atom Transfer to Substrates, and Oxo Exchange with Solvent Water Oleg Pestovsy* and Andreja Baac* Contents 1) Typical GC-MS data for oxygen-18 exchange experiments. 3 ) Typical 1 P -NMR spectra for TPPMS oxidation by Fe a q O +. 3) Typical 1 H-NMR spectra for CoSR + oxidation by Fe a q O +. 4) Kinetic simulations for CoSR oxidation by Fe a q O +. 5) Derivations. 1

2 1) Typical GC-MS data for oxygen-18 exchange experiments. 1. GC-MS chromatogram for an experiment with: [DMSO = 31 mm, [Fe a q =.3 m M, [ H + 1 = M, 9 7 % H 8 O. Ozone was bubbled for 15 sec, d u r i n g which time, 11 mm of DMSO was oxidized. Acid was neutralized with a concentrated Na C O 3 solution prior to analysis. m/z = 94 Intensity m/z = 78 RIC Time / s. Mass spectra of DMSO (neat) and methyl sulfone (10 mm DMSO / 0. mm Fe a q + / 0.09 M HClO 4 oxidized by ozone bubbling for 3.5 minutes) in H O.

3 DMSO 63 sulfone Intensity m/z 3. Mass spectra of reaction mixtures obtained in oxidation of 15 and 113 mm of DMSO by Fe a q / ozone. After 30 and 60 sec of ozone bubbling, 8 and 16 mm of DMSO were oxidized, respectively. In the experiment with 113 mm DMSO, the largest pea at m/z = 78 was due to DMSO from incomplete separation between DMSO and methyl sulfone at such high DMSO, concentration Conditions: [ D M S O = 15 mm, 113 mm [Fe a q = 0.40 mm [ H + = 0.1 M, 90 % H 18 O, ozone was bubbled for 30 sec, 60 sec 78 [DMSO = 15 mm 113 mm Intensity m/z 3

4 ) 3 1 P -NMR spectra of the product mixtures in oxidation of TPPMS by Fe a q /O 3 system in the absence (a) and presence (b) of DMSO. Ozone and Fe a q + were allowed to react prior to TPPMS injection. Conditions: [Fe a q = 0.19 mm [ O 3 = 0.17 mm [TPPMS = 1.0 mm [DMSO = 0, 0.10M [HClO 4 = 0.10 M 30% D O, room temperature, 6 hour collection time (a) TPPMS oxide TPPMS (b) 4

5 3) Typical 1 H-NMR spectra in CoSR + /Fe aq /O 3 reaction at room temperature. Collections times were 5 min for the four bottom spectra and 1 hour for the top spectrum. Peas unique to each cobalt complex are circled. Large water pea at 4.6 ppm is not displayed. S+Fe+O 3 S+O 3 S(O) S(O) S δ / ppm S 5 4 m M C o S R + in D O. Two sets of multiplets at 1.95 and.1 ppm, unique for C o S R + in this spectral region, were used to quantify this complex. 5

6 S(O) CoS(O)R + from oxidation of 54 mm CoSR b y 8 6 m M H O in 10 minutes. A set of three doublets at. ppm, unique to CoS(O)R + in this region, were used to quantify this complex. S(O) CoS(O) R + from oxidation of 54 mm CoSR b y 0. 9 M H O in 1 hours. A multiplet at 3.35 ppm, unique to CoS(O) R + in this region, was used to quantify this complex. S+O 3 Product mixture from oxidation of 54 mm CoSR + in D O by bubbling ozone for 5 sec. The mixture contained primarily CoS(O) R, as indicated by a large characteristic multiplet at 3.35 ppm. Traces of CoSR and CoS(O)R + are apparent from thei r characteristic peas at 1.95/.1 and. ppm, respectively. S+Fe+O 3 Product mixture from oxidation of 0.51 mm CoSR + by 0.46 mm Fe + a q / 0.37 mm O 3 in 0.10 M DClO 4 in D O. The mixture contained CoS(O) R +, as indicated by a characteristic multiplet at 3.35 ppm, and CoSR, as indicated by a set of multiplets at 1.95 and.1 ppm. Both CoSR + and CoS(O)R were stable toward autoxidation under these conditions for at least 3 hours, as determined by UV -Vis spectrophotometry of CoS(O)R + at 365 nm. 6

7 4) Kinetic simulations for CoSR oxidation by Fe a q O CoSR + + Fe a q O + CoS(O)R + + Fe a q + (15) 16 CoS(O)R + Fe aq O CoS(O) R + + Fe a q + (16) For a consecutive inetic scheme with a common reagent represented by equations 15 and 16, the exact algebraic solution for product yields as a function of starting reagent concentrations and rate constants is not available. In the first approximation, assuming pseudo-first-order condition for CoSR, the following rate expressions can be derived. d[feo dt d dt = { + } = [FeO { } 0 0 [FeO d[feo d + = d[feo d + 1+ = Integration of the last equation above would resul t in an expression for which solution for against [FeO + 0 in an explicit form is not nown (Capellos, C.; Bielsi, B. H. J. In Kinetic Systems: Mathematical Description of Chemical Kinetics in Solution; W i l e y- Interscience: New Yor, 197, pp ). However, it is easy to see that such a relationship would depend only on the ratio of rate constants ρ = / 15 and not their absolute values. While such mathematical problems can be solved by iterations, we employed a far easier and more reliable method, which did not depend on the pseudo- 7

8 first-order assumption: the ratio ρ was determined in inetic simulations for the experimental data in the absence of DMSO (Table, Main Text), by adjusting ρ until simulated yields of CoS(O)R + and CoS(O) R + matched those determined in experiment. This analysis gave ρ =13. The simulations were then carried out for the data in the presence of DMSO, with eqs 15,16, and 11. ( C H 3 ) SO + Fe aq O 11 (C H 3 ) S O + Fe aq ( 11 ) This time, ρ was ept constant while the absolute v a l u e s o f and were varied from the initial estimate ( = 10 7 M -1 s -1, obtained as described in Main Text) until simulated yields matched those from experiment. Table S1 shows experimental and simulated product yields obtained in this procedure. Table S1. Experimental and simulated product yields in oxidation of CoSR + by Fe + a q /O 3 system in the absence and in the presence of DMSO. Product concentrations Reagent concentrations Experimental Simulated + Fe a q O 3 C o S R + D M S O CoS(O)R + CoS(O) R CoS(O)R + CoS(O) R / M ~

9 5) Derivation of eq. 3, 4, 5, and 13. Equation 3 a) Beer s law: Abs 510 = [Fe III ε III [Fe II ε II b) Beer s law: Abs 41 = [Fe III ε III [Fe II ε II 4 1 c) {a ε ΙΙΙ 4 1 / ε ΙΙΙ }: Abs 510 ε ΙΙΙ 4 1 / ε ΙΙΙ = [Fe III ε III [Fe II ε II ε ΙΙΙ 4 1 / ε ΙΙΙ d) {c b}: Abs 510 ε ΙΙΙ 4 1 / ε ΙΙΙ Abs 41 = [Fe II ε II ε ΙΙΙ 41 / ε ΙΙΙ [Fe II ε II 4 1 e) Rearrange d: Abs 510 ε ΙΙΙ 4 1 / ε ΙΙΙ Abs 41 = [Fe II (ε II ε ΙΙΙ 41 / ε ΙΙΙ ε II 4 1 ) [Fe II = (Abs ε ΙΙΙ 41 / ε ΙΙΙ Abs 41 ) / (ε II ε ΙΙΙ 4 1 / ε ΙΙΙ ε II 4 1 ) [Fe II = (Abs R - Abs 41 ) / (ε II R - ε II 4 1 ) Equation 4 a) Rate definition and pseudo -first-order conditions: d[fe III / dt = Fe [FeO + [Fe II 0 b) Rate definition and pseudo -first-order conditions: d [ S 1 O / dt = S1 [FeO + [ S 1 0 c) {a / b}: d[fe III / d [ S 1 O = Fe [Fe II 0 / ( S1 [ S 1 0 ) d) Integrate c from zero to infinity: 9

10 [Fe III / [ S 1 O = Fe [Fe II 0 / ( S1 [ S 1 0 ) [ S 1 O = [Fe III S1 [ S 1 0 / ( Fe [Fe II 0 ) e) Stoichiometry: [Fe III / + [S 1 O = [ O 3 0 f) Substitute d into e: [Fe III / + [Fe III S1 [ S 1 0 / ( Fe [Fe II 0 ) = [O 3 0 g) Rearrange f: [Fe III (1/ + S1 [ S 1 0 / ( Fe [ F e II 0 )) = [O / [Fe III = 1 / [ O 3 0 (1/ + S1 [S 1 0 / ( Fe [Fe II 0 )) 1 / [Fe III = 1 / ( [ O 3 0 ) (1 + S1 [S 1 0 / ( Fe [Fe II 0 )) Equation 5 a) Similar to Equation 4 d: [ S 1 O = [ S O S1 [S 1 0 / ( S [ S 0 ) b) Stoichiometry: [ S O + [ S 1 O = [ O 3 0 c) Substitute a into b: [ S O + [ S O S1 [S 1 0 / ( S [ S 0 ) = [O 3 0 d) Rearrange c: [ S O (1 + S1 [S 1 0 / ( S [S 0 )) = [O 3 0 [ S O = [ O 3 0 / (1 + S1 [ S 1 0 / ( S [ S 0 )) [ S O = [ O 3 0 S [S 0 / ( S [S 0 + S1 [S 1 0 ) Equation 13 a) Rate definition and pseudo-first-order conditions: 10

11 d[ 16 O / dt = DMSO [FeO + [DMSO 0 b) Rate definition and irreversibility after isotope exchange: d[ 18 O / dt = ex [FeO + c) {a / b}: d[ 16 O / d[ 18 O = DMSO [DMSO 0 / ex d) Integrate c: [ 16 O / [ 1 8 O = DMSO [DMSO 0 / ex e) {1 / (1 + d)}: 1 / (1 + [ 16 O / [ 18 O ) = 1 / (1 + DMSO [DMSO 0 / ex ) [ 18 O / ([ 18 O + [ O ) = ex / ( ex + DMSO [DMSO 0 ) %[ 18 O = 100 ex / ( ex + DMSO [DMSO 0 ) 11