SUPPORTING INFORMATION
Electrocatalytic Reduction of C–C π-bonds via a Cobaltocene- Derived Concerted Proton-Electron Transfer Mediator: Fumarate Hydrogenation as a Model Study
Joseph Derosa†, Pablo Garrido-Barros†, and Jonas C. Peters*
Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States
Table of Contents
S-2 S1. General Experimental Information S-2 S1.1 Chemical/Reagent Considerations S-2 S1.2 NMR Spectroscopy S-2 S1.3 Electrochemistry
S-3 S2. Synthetic Details S-3 S2.1 Fumarate Ester Synthesis S-5 S2.2 NMR Spectra
S-11 S3. Controlled Potential Coulometry (CPC) NMe S-11 S3.1 eCPET Reduction of Fumarate Esters using [(Cp)Co(Cp 2)][OTf] S-14 S3.2 NMR Spectra NMe S-16 S3.3 Control Reaction with Cp2Co instead of [(Cp)Co(Cp 2)][OTf]
S-17 S4. Kinetic Analysis S-17 S4.1 General Introduction NMe H + S-17 S4.2 Kinetic Analysis of CPET by [(Cp)Co(Cp 2 )] S-21 S4.3 Error analysis S-22 S4.4 Calculation of the rate of protonation
S-23 S5. Cyclic Voltammetry
S-34 S6. Computational Details
S-54 S7. References
S-1 S1. General Experimental Information
S1.1 Chemical/Reagent Considerations:
Unless otherwise noted, all materials were used as received from commercial sources without further purification. Fumaryl chloride, phenol, cyclohexanol, 4-trifluoromethylphenol, 4- chlorophenol, 4-fluorophenol, 4-methoxyphenol, 4-cyanoaniline, and tetrabutylammonium hexafluorophosphate were used as purchased from Aldrich, Alfa Aesar, Oakwood, and Combi- NMe 1 Blocks. N,N-dimethylaniline-4-cobaltocenium triflate [CpCoCp 2][OTf], anilinium triflate 2 4-CN 3 acids, deuterosubstituted 4-cyanoaniline ( PhND2), were synthesized according to previously reported procedures. Teflon-coated magnetic stir bars were soaked in concentrated nitric acid for at least 1 h, washed repeatedly with deionized water then acetone, and dried in an oven prior to use. In air- or moisture-sensitive reactions, solvents were deoxygenated and dried by thoroughly sparging with N2 followed by passage through an activated alumina column in a solvent purification system by SG Water, USA LLC. Non-halogenated solvents were tested with sodium benzophenone ketyl in tetrahydrofuran (THF) in order to confirm the absence of oxygen and water. Deuterated solvents were purchased from Cambridge Isotope Laboratories, Inc., degassed, and dried over activated 3- Å molecular sieves prior to use.
S1.2 NMR Spectroscopy:
1H, 13C, and 19F spectra were recorded with Varian 400 MHz and Bruker 500 MHz spectrometers. Spectra were internally referenced to SiMe4 or solvent signals. The following abbreviations (or combinations thereof) were used to explain multiplicities: b = broad, s = singlet, d = doublet, t = triplet, q = quartet, p = pentet, sept = septet, and m = multiplet.
S1.3 Electrochemistry:
A CHI instruments 600B electrochemical analyzer was used for all electrochemical data collection. Cyclic voltammetry (CV), linear sweep voltammetry (LSV) and differential pulse voltammetry (DPV) experiments were carried out in a one-compartment three-electrode cell using a boron doped diamond (BDD) disk as the working electrode (3 mm diameter), a Pt wire as the counter electrode, and a Ag/AgOTf (5 mM) reference electrode. Details for the CVs and LSVs are noted as they appear. DPVs were obtained with the following parameters: amplitude = 50 mV, step height =4 mV, pulse width = 0.05 s, pulse period = 0.5 s and sampling width= 0.0167 s. E1/2 values for the reversible waves were obtained from the half potential between the oxidative and reductive peaks and for irreversible processes are estimated according to the potential at the imax in DPV measurements. For all measurements IR compensation was applied accounting for 85% of the total resistance. All of the reported potentials are referenced to the ferrocenium/ferrocene couple (Fc+/0).
S-2 S2. Synthetic Details
S2.1 Fumarate Ester Synthesis:
O O 2 equiv NEt3 Cl O R Cl + R OH R O º O 2 equiv DCM, 0 C to rt, 12h O
Figure S1. Synthesis of fumarate esters using fumaryl chloride and alcohols.
General Procedure for Fumarate Ester Synthesis: To a 100-mL round-bottomed flask equipped with a Teflon-coated stir bar was added a solution of triethylamine (10 mmol, 2 equiv, 1.39 mL) and fumaryl chloride (5 mmol, 1 equiv, 0.546 mL) in anhydrous dichloromethane (15 mL) and cooled to 0 ºC. While stirring, a solution of appropriate alcohol (5 mmol, 1 equiv) in anhydrous dichloromethane (5 mL) was added dropwise. The reaction mixture was allowed to stir at 0 ºC and naturally warm to room temperature over 12 h. The reaction mixture was then washed with 1M HCl solution (60 mL) and extracted with DCM (4 × 50 mL). The organic layers were combined, and the solvent was removed in vacuo to yield corresponding powders or oils. Purification by washing solid residue with ethyl acetate or column chromatography gave the pure product.
O diphenyl fumarate (1a): The title compound was prepared from phenol O (10 mmol, 2 equiv, 940 mg), according to the general fumarate ester O O synthesis procedure. Purification by washing dark brown residue with 1a ethyl acetate and filtering gave the pure product as a white solid (992 1 mg, 74% yield). H NMR (400 MHz, CDCl3) δ 7.43 (t, J = 7.9 Hz, 4H), 7.29 (t, J = 7.5 Hz, 2H), 13 7.25 (s, 2H), 7.18 (d, J = 8.0 Hz, 4H); C NMR (100 MHz, CDCl3) δ 161.94, 150.39, 134.19, + + 130.59, 126.91, 121.40. MS (ESI) mass calculated for C16H13O4 [M+H] 269.1, found 269.1. The characterization data is in agreement with previous reports.4
CF3 bis(4-(trifluoromethyl)phenyl) fumarate (1b): The title O O compound was prepared from 4-trifluoromethylphenol (10 O O mmol, 2 equiv, 1.62 g), according to the general fumarate ester 1b F3C synthesis procedure. Purification using silica gel column chromatography (92:4:4 hexanes:EtOAc:DCM) gave the pure product as a white solid (1.21 g, 1 61% yield). H NMR (400 MHz, CDCl3) δ 7.71 (d, J = 8.5 Hz, 4H), 7.32 (d, J = 8.5 Hz, 4H), 13 7.27 (s, 2H); C NMR (100 MHz, CDCl3) δ 162.56, 152.72, 134.62, 128.91 (q, JC–F = 33.0 Hz), 19 127.18 (q, JCF = 3.7 Hz), 125.22 (q, JC–F = 271.0 Hz), 121.95; F NMR (400 MHz, CDCl3) δ - + + 62.35. MS (ESI) mass calculated for C18H11F6O4 [M+H] 405.1, found 405.1.
Cl O bis(4-(chloro)phenyl) fumarate (1c): The title compound was O O prepared from 4-chlorophenol (10 mmol, 2 equiv, 1.28 g), O according to the general fumarate ester synthesis procedure. 1c Cl Purification by washing dark brown residue with ethyl acetate and
S-3 1 filtering gave the pure product as a white solid (1.43 g, 85% yield). H NMR (400 MHz, CDCl3) 13 δ 7.39 (d, J = 8.9 Hz, 4H), 7.22 (s, 2H), 7.13 (d, J = 8.8 Hz, 4H); C NMR (100 MHz, CDCl3) δ 162.58, 148.39, 134.20, 131.65, 131.10, 127.75, 122.42. MS (ESI) mass calculated for + + C16H11Cl6O4 [M+H] 337.0, found 337.0.
OMe O bis(4-(methoxy)phenyl) fumarate (1d): The title compound O O was prepared from 4-methoxyphenol (10 mmol, 2 equiv, 1.36 O g), according to the general fumarate ester synthesis procedure. MeO 1d Purification using silica gel column chromatography (70:15:15 hexanes:EtOAc:DCM) gave the pure product as an off-white solid (853 mg, 52% yield). 1H NMR (400 MHz, CDCl3) δ 7.21 (s, 1H), 7.09 (d, J = 9.1 Hz, 2H), 6.93 (d, J = 9.1 Hz, 2H), 3.62 13 (s, 6H); C NMR (100 MHz, CDCl3) δ 163.70, 158.17, 144.54, 135.87, 123.81, 114.70, 55.75. + + MS (ESI) mass calculated for C18H17O6 [M+H] 329.1, found 329.1.
O dicyclohexyl fumarate (1e): The title compound was prepared from O O cyclohexanol (10 mmol, 2 equiv, 1.3 mL), according to the general O 1e fumarate ester synthesis procedure. Purification using silica gel column chromatography (96:4 hexanes:EtOAc) gave the pure product as a 1 colorless oil (1.03 g, 69% yield). H NMR (400 MHz, CDCl3) δ 6.82 (s, 2H), 4.86 (tt, J = 8.9, 4.0 Hz, 2H), 1.87 (dd, J = 9.8, 4.6 Hz, 4H), 1.79–1.70 (m, 4H), 1.61–1.27 (m, 12H); 13C NMR
(100 MHz, CDCl3) δ 234.50, 164.67, 134.06, 73.38, 31.61, 25.43, 23.76. MS (ESI) mass + + calculated for C16H25O4 [M+H] 281.2, found 281.2. The characterization data is in agreement with previous reports.5
S-4 S2.2 NMR Spectra
S-5
S-6
S-7
S-8
S-9
S-10 S3. Controlled Potential Coulometry (CPC)
NMe S3.1 eCPET Reduction of Fumarate Esters using [(Cp)Co(Cp 2)][OTf]:
NMe 1 mM [(Cp)Co(Cp 2)][OTf] 200 mM [TBA][PF ] in DME O 6 H O 100 mM TsOH O R O R R O R O +/0 O - 1.30 V vs Fc O H 50 mM 20–48 h Figure S2. Optimized CPE conditions for fumarate ester reduction using an eCPET mediator.
General CPC Procedure: GC electrodes were pretreated by polishing with 1, 0.3 and 0.05 μm alumina paste followed by rinsing with water and acetone. The BDD electrodes were pre-treated according to literature procedures.6 Controlled potential coulometry (CPC) experiments were carried out in a gas-tight single compartment cell using a BDD plate (dimensions 1x2 cm) working electrode, a Ag/AgOTf (5 mM) reference electrode, and a GC plate (dimensions 1x1 cm) counter electrode. The solution was stirred throughout the CPC. In a typical experiment, a 3 mL solution of 0.2 M [TBA][PF6] in DME was added to the electrochemical cell. Then, 52.0 mg of toluenesulfonic acid (100 mM) and appropriate amount of fumarate ester (50 mM) were NMe added. In experiments using cobaltocene as catalyst, either 1.3 mg of [CpCoCp 2][OTf] (1 mM) or 0.8 mg of [Cp2Co] (1 mM) were then added. After the appropriate reaction time, the solution was quenched with 2 M HCl in ether (1 mL). After 5 min of stirring, the solvent was evaporated under reduced pressure until dryness. The resulting solids were dissolved in ether (20 mL) and the solution was subsequently washed with aq. 0.1 M Na2CO3 solution (20 mL) and extracted with ether (5 x 20 mL). The organic layers were combined, dried over Na2SO4, and 1 concentrated in vacuo. A crude H NMR was taken with CH2Br2 as internal standard and analyzed. Purification by preparative thin-layer chromatography (PTLC) gave the pure product.
Recapitulation of the optimized conditions based on our previous report (Ref. 1): While anilinium and pyridinium acids within the pKa range to protonate the [Co] show similar results in terms of CV, they are not suitable for long-term CPC experiments. Anilinium acids are easily oxidized at the counter electrode while pyridinium acids present large adsorption behavior on the surface of electrodes as already reported in the literature (Ref. 20). In this context, tosic acid is an ideal choice given its pKa and its inert behavior upon interaction with electrodes under our operating conditions. As the working electrode, GC and ITO/FTO electrodes present substantial HER activity in the presence of acids with suitable pKa values for our desired reactivity. BDD, in contrast, presents lower background reactivity enabling productive CPET with the mediator. As the counter electrode, we found that appropriate sacrificial metal electrodes, such as Al, passivate during long term experiments preventing the productive pass of current at the cathode for the targeted reductive processes. This led us to consider solvent oxidation as counter reaction. A Pt anode for the oxidation of DME shows issues regarding strong adsorption of organic substrates, sequestering them from our targeted reduction process. In contrast, GC is efficient to oxidize DME under our operating conditions without interacting with the substrate. Finally, other solvents suitable for the CVs such as MeCN and THF present side reactivity under acidic media and the operating reduction potentials during long-term CPC experiments, leading to some degree of polymerization. In contrast, DME is more stable against such side reactivity.
S-11 Selected Optimization of Conditions for CPC with Dicyclohexyl fumarate: To provide some insight on the various effects of mediator, substrate, and tosic acid concentration, we have selected representative data to illustrate the importance of these effects:
X mM [(Cp)Co(CpN)][OTf] 200 mM [TBA][PF ] in DME O 6 H O Z mM TsOH O O O O +/0 O - 1.30 V vs Fc O H Y mM 48 h
entry X Y Z % yield product % SM remaining
1 1 50 100 47 37
2 0 50 100 2 84
3 1 100 300 11 63
4 1 25 100 8 71
5 1 50 150 22 56
6 2 50 100 76 3
Table S1: Controlled potential coulometry (CPC) screening by varying mediator (X), substrate (Y), and acid (Z) concentrations for the optimization of eCPET for dicyclohexyl fumarate.
O diphenyl succinate (2a): The title compound was prepared from O O diphenyl fumarate, 1a, (50 mM, 0.15 mmol) according to the general O 2a CPC procedure for 20 h. Purification using PTLC (96:2:2 hexanes:EtOAc:DCM) gave the pure product as a white solid (36.1 mg, 1 86% yield). H NMR (400 MHz, CDCl3) δ 7.39 (d, J = 7.4 Hz, 4H), 7.24 (t, J = 7.4 Hz, 2H), 13 7.10 (d, J = 7.4 Hz, 4H), 3.01 (s, 4H); C NMR (100 MHz, CDCl3) δ 172.12, 151.98, 129.61, + + 125.57, 120.95, 29.44. MS (ESI) mass calculated for C16H15O4 [M+H] 271.1, found 271.1. The characterization data is in agreement with previous reports.7
S-12 NMe Figure S3. Controlled potential coulometry (CPC) using diphenyl fumarate with [CpCoCp 2][OTf] (left) and without a mediator (right).
O dicyclohexyl succinate (2e): The title compound was prepared from O O dicyclohexyl fumarate, 1f, (50 mM, 0.15 mmol), according to the O 2e general CPC procedure for 48 h. Purification using PTLC (96:2:2 hexanes:EtOAc:DCM) gave the pure product as a colorless oil (mg, 47% 1 yield). H NMR (400 MHz, CDCl3) δ 4.76 (td, J = 8.9, 4.1 Hz, 2H), 2.59 (s, 4H), 1.86–1.78 (m, 4H), 1.71 (dd, J = 8.4, 3.4 Hz, 4H), 1.52 (ddd, J = 11.4, 5.6, 2.7 Hz, 2H), 1.47–1.19 (m, 10H); 13 C NMR (100 MHz, CDCl3) δ 170.71, 72.89, 31.54, 29.63, 25.34, 23.68. MS (ESI) mass + + calculated for C16H27O4 [M+H] 283.2, found 283.2. The characterization data is in agreement with previous reports.7
Figure S4. Controlled potential coulometry (CPC) using dicyclohexyl fumarate with NMe [CpCoCp 2][OTf] (left) and without a mediator (right).
Selected examples of unsuccessful CPCs with different substrate classes:
1 mM [(Cp)Co(CpN)][OTf] 200 mM [TBA][PF ] in DME 6 H 100 mM TsOH R R R R +/0 - 1.30 V vs Fc H 50 mM 20–48h h
unsuccessful examples O O
Me background reduction reversible by CV* reversible by CV* reversible by CV* below CoIII/II couple trace SM/ 31% SM/ 70% SM/ 76% SM/ no products detected product not detected product not detected product not detected
* after the addition of catalyst, the feature at -1.30 V corresponding to the CoIII/II couple was reversible, indicative of a lack of sufficient electrochemical catalysis Table S2. Selected examples of unsuccessful substrates under optimized conditions.
S-13 S3.2 NMR Spectra:
S-14
S-15 NMe S3.3 Control Reaction with Cp2Co instead of [(Cp)Co(Cp 2)][OTf]
1 mM Cp2Co 200 mM [TBA][PF ] in DME O 6 H O 100 mM TsOH O O O O +/0 O - 1.30 V vs Fc O H 50 mM 20 h 9% by 1H NMR (32% SM)
CH2Br2
H H O O O H H
O H CO2Ph H PhO2C H H 4 H 4 H
Figure S5. (Top) Control CPC using 1mM Cp2Co under optimized conditions leads to low conversion 1 measured by H NMR using CH2Br2 as internal standard. (Bottom) CPC profile using diphenyl fumarate with Cp2Co.
S-16 S4. Kinetic analysis
S4.1 General Introduction:
The kinetic studies in the present work are analyzed within the frameworks developed by Savéant and coworkers for multielectron-multistep catalytic reactions.8 These frameworks enable extraction of mathematical information about the observed reaction rate (kobs) based on the plateau current during an ideal S-shaped catalytic process (icat). In this plateau current regime, the reaction is only limited by chemical steps involved in the catalysis since electron transfer steps at the electrode feature much higher kinetic rates. Therefore, this kobs can be related to the rate determining step or a convolution of a rate limiting steps along the catalytic cycle by assuming a mechanism as detailed below for our assumed mechanisms. Herein, we are evaluating icat as the maximum current of the electrocatalytic wave obtained from background corrected CVs due to the proximity to ideal catalytic response. This was further corroborated by calculating kobs using the Foot-of-the-wave analysis, developed for conditions where the CV response is affected by side phenomena such as substrate consumption or catalyst deactivation (vide infra).9 The similar values obtain from both methodologies demonstrate the well-behaved catalytic current close to ideal response. These methodologies together with the kobs calculation are detailed below.
NMe H + S4.2 Kinetic Analysis of CPET by [(Cp)Co(Cp 2 )] :
Scenario 1. Catalytic CPET plus free radical reductive protonation:
This mechanism for the electrocatalytic CPET reaction is shown in Figure S6 and parallels that followed 1 by the electrocatalytic CPET to acetophenone previously described. This consists of an ECcat step involving rate limiting CPET by the mediator to generate the free fumaryl radical, followed by an EC step involving reductive protonation of this radical at the electrode to provide the hydrogenated product. Such reactions are thus modelled by Eq. S1 and S2 respectively, and the overall observed catalytic current is the addition of the current obtained due to both processes.
� = 2��� � � [���] Eq. S3
� = 0.496��� · Eq. S2 ·
� = � + � Eq. S3
0 In these equations, F is the Faraday constant, S is the surface of the electrode, Cx is the standard concentration of compound X, Dx is the diffusion coefficient of compound X, v is the scan rate, R is the ideal gas constant, and T is the temperature. The catalytic current provided by the ECcat is thus dependent NMe only on the concentration of mediator and substrate DPF. Measurements of the kinetic [CpCoCp 2] protonation (vide infra) support that the CPET is the rds and disfavor the involvement of the concentration of acid, [H+], in the rate law of the CPET process. On the other hand, the contribution of the following EC step to the catalytic current only depends on the concentration of the free radical intermediate and will be given by Eq. S2, similar to the current obtained for a Nernstian wave following the Randles-Sevcik equation.10 Overall, the catalytic current obtained within this mechanistic scenario presents zeroth order in acid, opposite to the experimental observations of a partial positive order under certain conditions. In addition, this mechanism would likely generate a product distribution including C-C bond products from free radical or anion dimerization/oligomerization as previous electrocatalytic examples, inconsistent with the observed selectivity towards the hydrogenated product
S-17
Figure S6. Mechanistic scenario for hydrogenation of DPF via ECcat process consisting of electrocatalytic CPET plus free radical reductive protonation at the electrode (EC).
S-18 Scenario 2. CPET via catalytic ECEC:
This mechanism for the electrocatalytic CPET reaction is shown in Figure S7 and follows a 2e- + 8 NHMe 2+ /2H reaction via catalytic ECEC mechanism. In this case, upon reduction of [CpCoCp 2] to NHMe + generate the species [CpCoCp 2] (E), a CPET to the DPF substrate takes place in a chemical step (C) to generate an intermediate radical species. This species is then reduced by one electron and protonated to NMe + generate the hydrogenated product and [CpCoCp 2] , the latter being further protonated to regenerate NHMe 2+ the mediator [CpCoCp 2] . Since the protonation of the mediator features a rate constant in the order 7 -1 of 10 M·s , the kobs is a convolution of the CPET (kCPET) and proton transfer to the anion intermediate (kPT,1). This mechanism does not necessarily involve the formation of an intermediate via interaction the NMe + fumaryl radical and the [CpCoCp 2] , as far as its reduction to the fumaryl anion and further interaction NMe + NMe 2+ with [CpCoCp 2] is fast enough outcompete [CpCoCp 2] protonation, leading to formation of an intermediate whose protonation release the final product and regenerate the initial cobalt mediator.
Figure S7. Mechanistic scenario for hydrogenation of DPF via an electrocatalytic ECEC mechanism consisting of an initial CPET and a further reductive protonation of a radical intermediate at the electrode before regeneration of the molecular mediator.
S-19 For this ECEC mechanism, the ideal behavior of the catalytic current is modelled by Eq. S4, where kobs includes the rates of the consecutive CPET and PT reactions via Eq. S5. This relationship makes evident the interplay of the rate for the two processes and the influence of both [DPF] and [H+]. + Accordingly, if the rate of the CPET is rds (kCPET[DPF] << kPT[H ]), kobs mainly reflect the rate of the CPET and the overall catalytic process will follow first order in DPF and Co mediator. On the other hand, + when kCPET[DPF] >> kPT[H ], the proton transfer becomes rate limiting and the catalytic current will show + first order in [H ] and Co mediator. For intermediate situations, where both steps feature similar rates, kobs will reflect the contribution of both steps with partial order in both [DPF] and [H+] according to the rate law expressed in Eq. S5, and the catalytic current will depend on both [DPF] and [H+] following Eq. S6
� = 2��� � � Eq. S4
= + Eq. S5
� = 2��� � Eq. S6
Dividing Eq. S6 by Eq. S7, which represents the intensity of the one-electron reduction of the Co mediator (ip) obtained from the Randles-Sevcik equation, simplifies the mathematical treatment for the determination of kobs without the requirement of estimation of Dcat via Eq S8. Therefore, kobs values in this work were obtained by acquiring cyclic voltammograms at different scan rates and by plotting icat/ip versus 1/n, which allows calculation of kobs from the slope of the linear fitting.
� = 0.4463��� Eq. S7
= 2.24 � � Eq. S8
The previously described methodology is suitable for cyclic voltammetry that follow an ideal S-shape response. Savéant and coworkers have also suggested that in cases with non-ideal catalytic responses, an alternative approach, termed foot-of-the-wave analysis (FOWA), is more suitable for extracting kinetic information.9 It is based on the current variation at the beginning of the catalytic process where there is less time for deviations from ideal behavior (e.g., substrate consumption, catalyst decomposition, etc.) to effect the rate analysis. The FOWA for an ECEC catalytic mechanism is represented by Eq. S9, in which ic is the current at a given potential E under the catalytic conditions and ip is the current of a 1 electron NHMe 2+ wave, the one of [CpCoCp 2] in this case. The Ecat/2 is the potential at which half of the maximum catalytic current is achieved.
· . = Eq. S9 [ ] /
In this case, the value for kobs obtained from peak current analysis assuming ideal S-shape -1 is 14.15 s , which is similar to the kobs value obtained from FOWA under identical conditions, 14.20 s-1. This suggests that the catalytic system is well-behaved and that the catalysis is close to the pure kinetic regime. For simplicity, we have employed the simpler S-shape analysis for the
S-20 values presented in this work since analysis of the data with the more general FOWA does not alter any of the conclusions presented.
Evaluation of the kinetic in in terms of TOFmax can be done using Eq. S10, allowing for better comparison with other reactions that differ in their rate law.
��� = � Eq. S10
The kinetic isotope effect, KIE, was determined by evaluating kobs for the reaction in the 4-CN + 4-CN + presence of proteo-acid, [ PhNH3] , and deutero-acid, [ PhND3] , and comparing them as described in Eq. S11.
$ !"# ( ) ��� = % Eq. S11 !"# ( )
S4.3 Error analysis:
The analysis of the electrochemical data involves linear fit and extracting kobs from the slope (m) of those lines. Lines of best fit were generated using Excel and the LINEST function was used to determine the error in their slopes (merr). That error was then propagated to generate the error in kobs (kerr) as shown here in Eq. S12.
� = 2 × &'' (Eq. S12) .
For the KIE, the error (KIEerr) was determined as shown in Eq. S13.
$ % &''( ) &''( ) ��� = ��� $ % (Eq. S13) ()*( ) ()*( )
S-21 S4.4. Calculation of the rate of protonation:
NMe + Protonation of the cobaltocene species [CpCoCp 2] takes place prior reduction at the electrode to generate the strong CPET donor that promotes formal H atom transfer to the unsaturated substrate. In order to estimate the kinetic rate of this step, we have evaluated the CV NMe + response of [CpCoCp 2] in the presence of stoichiometric amount of tosic acid. The difference 1 of their pKa values (8.6 and 8.0 respectively) determines a Keq for the protonation of 4.0. NMe + Accordingly, addition of 1 eq of tosic acid to a 1 mM solution of [CpCoCp 2] yields only partial protonation of the cobaltocene species, evidenced by the obtained orange color resulting NMe + NHMe 2+ from the mixture of deep red [CpCoCp 2] and bright yellow [CpCoCp 2] . Upon +/0 NHMe 2+ electrochemical reduction at -1.30 V vs Fc , [CpCoCp 2] is consumed to generate NHMe + NHMe 2+ [CpCoCp 2] promoting a shift in the equilibrium towards protonated [CpCoCp 2] . Therefore, this process can be modelled as a CE mechanism as represented in Figure S8. Estimation of the rate constant of protonation (kPT) has been performed using the equations that described the current intensity of the reduction peak and the shift in the peak potential (Ep,c) upon variation of the scan rate, as described in the literature.10 By scanning at increasing rates, the behavior of the voltammetry can be switched to a plateau-shape reduction peak corresponding to a kinetic regime (KP) where Equations S14 and S15 apply, allowing for direct calculation of the 7 -1 -1 kPT (2.74•10 M s ). Similar methodologies have been previously applied for protonation of cobalt half-sandwiches species following EC mechanism.
� = ��� � � � � Eq. S14 � = � − 0.17 + �� Eq. S15 / /
NMe + Figure S8. Mechanism for the protonation of [CpCoCp 2] , following an CE mechanism.
S-22 S5. Cyclic Voltammetry
NMe 4- Figure S9. Cyclic voltammograms of a DME solution containing 1 mM [CpCoCp 2][OTf], 50 mM [ CN PhNH3][OTf], and 0.1 M [TBA][PF6] at different scan rates. The cathodic peak current from this type of experiment, ip,c, is employed for the kinetic analysis in order to extract kobs.
NMe 4- Figure S10. Cyclic voltammograms of a DME solution containing 1 mM [CpCoCp 2][OTf], 50 mM [ CN PhNH3][OTf], 50 mM of DPF as substrate, and 0.1 M [TBA][PF6] at different scan rates, showing a large electrocatalytic current.
S-23
NMe 4- Figure S11. Cyclic voltammograms of a DME solution containing 1 mM [CpCoCp 2][OTf], 50 mM [ CN PhNH3][OTf], 50 mM of DPF as substrate, and 0.1 M [TBA][PF6] at different scan rates. The current was normalized by the square root of the scan rate, reflecting the catalytic behavior as the slower scan rates feature the higher currents.
Figure S12. Background corrected cyclic voltammograms of a DME solution containing 1 mM NMe 4-CN [CpCoCp 2][OTf], 50 mM [ PhNH3][OTf], 50 mM of DPF as substrate, and 0.1 M [TBA][PF6] at different scan rates. The current at the catalytic peak, icat, from this corrected CVs was employed in the kinetic analysis to obtain kobs.
S-24
Figure S13. Cyclic voltammograms at 100 mV·s-1 of a DME solution containing 1 mM NMe 4-CN [CpCoCp 2][OTf], 50 mM [ PhNH3][OTf], 0.1 M [TBA][PF6], and increasing concentrations of DPF as substrate. The catalytic peak current features a larger initial increase which decay for the higher concentrations of [DPF], revealing the change in the order in [DPF].
Figure S14. Cyclic voltammograms at 100 mV·s-1 of a DME solution containing, 50 mM [4- CN PhNH3][OTf], 50 mm DPF as substrate, 0.1 M [TBA][PF6], and increasing concentrations NMe [CpCoCp 2][OTf].
S-25
Figure S15. Cyclic voltammograms at 100 mV·s-1 of a DME solution containing, 50 mM [4- CN PhNH3][OTf], 50 mm DPF as substrate, 0.1 M [TBA][PF6], and increasing concentrations NMe [CpCoCp 2][OTf].
Figure S16. Cyclic voltammograms at 100 mV·s-1 of a DME solution containing 1 mM NMe 4- [CpCoCp 2][OTf], 20 mM DPF as substrate, 0.1 M [TBA][PF6], and increasing concentrations of [ CN PhNH3][OTf]. The catalytic peak current features only a slight increase reflecting an order in acid close to zero under this lower [DPF] conditions.
S-26
Figure S17. Cyclic voltammograms at 100 mV·s-1 of a DME solution containing 1 mM NMe 4- [CpCoCp 2][OTf], 50 mM DPF as substrate, 0.1 M [TBA][PF6], and increasing concentrations of [ CN PhNH3][OTf]. The catalytic peak current features a larger increase under this high [DPF] conditions, reflecting an increase in the order in acid.
Figure S18. (Left) Plot of the log(kobs) vs log([Co]) obtained from the kinetic analysis upon varying concentration of the mediator. (Right) Catalytic current obtained varying concentration of the mediator 4-CN + with constant [DPF] and [ PhNH3 ] (20 mM and 50 mM respectively) reflecting the first order in Co under low substrate concentration conditions.
S-27
Figure S19. (Left) Plot of the log(kobs) vs log([Co]) obtained from the kinetic analysis upon varying concentration of the mediator. (Right) Catalytic current obtained varying concentration of the mediator 4-CN + with constant [DPF] and [ PhNH3 ] (50 mM and 50 mM respectively) reflecting the first order in Co under higher substrate concentration conditions.
Figure S20. (Left) Cyclic voltammograms of a DME solution containing 1 mM NMe [CpCoCp 2][OTf], 1 mM TsOH, and 0.1 M [TBA][PF6] at different scan rates. The cathodic peak current from this type of experiment, ip,c, is employed for the kinetic analysis in order to extract kPT. (Right) Cyclic voltammograms of a DME solution containing 1 mM NMe -1 [CpCoCp 2][OTf], 50 mM TsOH, 50 mM of DPF and 0.1 M [TBA][PF6] at 100 mV·s .
S-28
Figure S21. Theoretical values for kobs obtained from Eq. 6 assuming a ECEC mechanism (Figure S7) upon varying the concentration of (left) DPF under different acid concetration conditions and (right) acid under two different DPF concentration conditions.
Figure S22. Cyclic voltammograms at 100 mV·s-1 of a DME solution containing 1 mM NMe 4-CN [CpCoCp 2][OTf], 50 mM [ PhNH3][OTf], 0.1 M [TBA][PF6], and 20 mM of different para- substituted diaryl fumarate as substrates.
S-29
Figure S23. CV and scan rate-dependence under optimized eCPET conditions using dicyclohexyl fumarate as substrate (top) and results from CPC (bottom). A boron-doped diamond (BDD) disk (CV) or plate (CPC) was used as working electrode, a Ag/AgOTf (5 mM) as reference electrode, and glassy carbon (GC) disk (CV) or plate (CPC) as counter electrode.
S-30 Figure S24. Rate-dependence analyses on substrate concentration (left) and acid concentration (right) using DCyF, evidencing a rate-limiting CPET step.
Figure S25. Cyclic voltammograms at 100 mV·s-1 of a DME solution containing 1 mM NMe 4- [CpCoCp 2][OTf], 50 mM DCyF as substrate, 0.1 M [TBA][PF6], and increasing concentrations of [ CN PhNH3][OTf]. The catalytic peak current features only a slight increase reflecting an order in acid close to zero.
Figure S26. Rate-dependence analyses on substrate concentration (left) and acid concentration (right) using DCyF, evidencing a rate-limiting CPET step.
S-31
Figure S27. Rate-dependence analyses on substrate concentration (left) and acid concentration (right) using DCyF, evidencing a rate-limiting CPET step.
Figure S28. Cyclic voltammograms at 100 mV·s-1 of a DME solution containing 1 mM NMe 4- [CpCoCp 2][OTf], 50 mM DCyF as substrate, 0.1 M [TBA][PF6], and 50 mM of either [ CN 4-CN PhNH3][OTf] (blue trace) or [ PhND3][OTf] (green trace). The difference in the catalytic peak current reflects the normal kinetic isotope effect. Inset: Kinetic analysis performed using the protio and deutero acids.
S-32 Figure S29. (left) Cyclic voltammogram of a DME solution containing 1 mM [CpCoCpNMe2][OTf], 50 4-CN mM [ PhNH3][OTf], 20 mM DPF and 0.1 M [TBA][PF6] and (right) representation of the corresponding foot-of-the-wave analysis. The red lines represent the region used for the FOWA in the linear fit and the dashed grey line represent the ideal response of a cyclic voltammetry featuring a -1 theoretical S-shape. The kCPET calculated this way is 14.2 s .
S-33 S6. Computational details
All DFT calculations were performed in the Gaussian 09,11 using the TPSS (meta-GGA)12 functional with def2-TZVPP13,14 on all atoms, Grimme-d3 dispersion correction,15 and, when explicitely indicated, SMD16 implicit solvation modelling acetonitrile for thermochemical parameters (for direct comparison with experimental available data) and DME for evaluation of intermediate structures.17 Geometry optimizations were computed in solution without symmetry restrictions. All calculated structures were stationary points as confirmed by single-point vibrational frequency calculations. Free energy corrections were calculated at 298.15 K and 105 Pa pressure, including zero point energy corrections (ZPE). Unless otherwise mentioned, all reported energy values are free energies in solution under standard state conditions.
Reduction potentials were determined via calculated exchange reactions with ferrocene/ferrocenium. The 18 pKa values were likewise determined via exchange reactions with 2-chloroanilinium/2-chloroaniline. The bond dissociation free energies (BDFEs) were calculated directly using the free energy of H∙. This DFT methodology has already proved to successfully reproduce the thermodynamic data associated to this catalytic system as reported in previous publications.1
S6.1. Thermochemistry of fumarates substrates. BDFE were calculated using MeCN as solvent with the SMD model.
S-34 S6.2. Investigation of potential intermediates:
Figure S30. Calculated equilibriums for the interaction between [CpCoCpNMe2]+ and (top) the organic fumaryl radical (bottom) the fumaryl anion, via non-covalent interactions including potential H-bonding and π-π stacking. Using the SMD to simulate DME solvent, this equilibrium is endergonic for both the radical and the anion when the potential energy is considered, with energy values of -10.2 and -14.9 kcal·mol-1 respectively. When the zero point vibrational correction was applied, the interaction with the fumaryl radical becomes slightly endergonic (2.3 kcal· mol-1) while the interaction with the fumaryl anion remains exergonic (-4.4 kcal· mol-1). The interaction between [CpCoCpNMe2]+ and the fumaryl radical was further investigated in the vacuum to exclude the influence of the solvation model, and a value of 0.4 kcal·mol-1, suggesting the possible existence of an equilibrium between both the fumaryl radical and [CpCoCpNMe2]+ which is sensitive to the DFT methodology employed with influence of the solvation model.19 Due to the low reduction potential of the fumaryl radical (-0.78 V vs Fc+/0) compared to the operating potential of -1.3V vs Fc+/0, and the potential equilibrium in its interaction with [CpCoCpNMe2]+ via non-covalent interactions, we propose that further protonation of [CpCoCpNMe2]+ with release of free fumaryl radical is comparatively slow to its reduction to the fumaryl anion and thermodynamically favorable interaction with [CpCoCpNMe2]+. These results are supported by the absence of any dimerization/oligomerization products that would be observed in the case of free diffusing organic radical/anion intermediates.
S-35
Figure S31. DFT optimize structure of [CpCoCpNMe2] and the organic fumaryl radical in THF using SMD solvation model upon initial CPET, showing the potential equilibrium between the free species and the adduct formed upon non-covalent interactions.
S6.1. Cartesian coordinates O 3.48715900 3.24298000 0.01880200
O 3.73344500 0.97469100 0.00875200
O -1.19866400 1.55015000 -0.01303900
C -2.60592600 1.42195800 -0.00966300 E= -918.176352 H C -3.27336000 1.40228600 1.20985100 C 0.99208600 0.65126900 -0.01481700 C -3.27991300 1.39373700 -1.22541300 H 1.60009200 -0.24673600 -0.03237300 C -4.66908200 1.35111200 1.20636100 C 1.54269400 1.87357000 0.01058800 H -2.70944400 1.42799000 2.13684000 H 0.93468700 2.77157500 0.02815300 C -4.67559000 1.34252600 -1.21399700 C -0.46498200 0.39636200 -0.01770200 H -2.72107300 1.41291600 -2.15562000 C 2.99976200 2.12847800 0.01353200 C -5.36998300 1.32110500 -0.00184300 O -0.95237900 -0.71814100 -0.02282100
S-36 H -5.20588800 1.33610200 2.15030800 O 2.79801500 1.45224600 -1.24986000
H -5.21746000 1.32071000 -2.15491400 O -0.31919200 1.65045700 -1.27277800
H -6.45529700 1.28336900 0.00121500 C -1.03635700 1.21780300 -0.13755000
C 5.14070700 1.10288400 0.00561600 C -0.37486200 0.55214800 0.89067600
C 5.81448200 1.13119000 1.22148300 C -2.38303700 1.55362000 -0.05537400
C 5.80835500 1.12247000 -1.21378200 C -1.09462100 0.21312900 2.03732400
C 7.21015900 1.18240300 1.21030700 H 0.67823200 0.31116100 0.79536000
H 5.25547800 1.11207600 2.15159300 C -3.09016700 1.21090900 1.09966700
C 7.20407700 1.17364400 -1.21005100 H -2.86144100 2.07475600 -0.87852900
H 5.24460100 1.09670000 -2.14086700 C -2.44924000 0.54119200 2.14440300
C 7.90476600 1.20373800 -0.00172600 H -0.59217200 -0.30531700 2.84869800
H 7.75186400 1.20428700 2.15131800 H -4.14206100 1.46916300 1.17900500
H 7.74104800 1.18858600 -2.15390500 H -3.00255200 0.27731800 3.04083800
H 8.99008000 1.24147400 -0.00459500 C 3.54058100 1.35654700 -0.06623200
C 3.16559200 2.06754000 1.07315000
C 4.60200000 0.45615700 -0.05121200
C 3.88306600 1.86925100 2.25311700
H 2.32564600 2.75231700 1.03600900 E= -918.74707 H C 5.30873600 0.26476300 1.13828400 C 1.62802000 2.62385600 -2.89272700 H 4.86073200 -0.08452900 -0.95624300 H 1.41786100 3.55070000 -3.41391600 C 4.95419600 0.97148700 2.28953800 C 0.14927300 0.70276100 -2.14502600 H 3.59875400 2.41610100 3.14752800 C 2.58586800 2.70218000 -1.81722400 H 6.13681300 -0.43773500 1.16057300 O -0.07887300 -0.47989200 -2.04773200 H 5.50621100 0.82093400 3.21253000 O 3.15503600 3.71774500 -1.43902400 C 0.93676700 1.36148500 -3.27333200
S-37 H 1.65046200 0.60721000 -3.62494600 C 4.55802400 1.61350400 0.75960600
H 0.22814000 1.54753700 -4.08740100 C 3.98200900 4.05684500 2.00795000
H 1.97314100 3.27120000 2.25801700
C 5.55110000 2.58719000 0.88975600
H 4.75511800 0.66090300 0.27720300
E= -918.754589783 H C 5.26478100 3.80498600 1.51307700
C 0.34048400 -3.07099200 0.94190600 H 3.75746600 5.00343100 2.49125500
C 2.04487200 0.05457500 2.06100700 H 6.54656200 2.39010800 0.50167900
O -0.50242700 -3.67103300 0.49792300 H 6.04011000 4.55902700 1.61054000
O 2.67200200 -0.04129600 3.09016700 C 1.40959000 -2.31009900 1.50480500
O 2.25923600 0.93589700 1.06691400 H 1.73487100 -2.81755200 2.42503400
O 0.16187100 -0.59044900 0.53064000 H 2.22037300 -2.33730000 0.75707500
C -0.73014700 0.48106500 0.50359100 C 0.86009800 -0.87571700 1.73698400
C -1.38192100 0.66353700 -0.71770300 H 0.19392400 -0.89054900 2.60496600
C -0.97371100 1.32264000 1.58898200
C -2.29472100 1.70625100 -0.85176400
H -1.16795400 -0.01047400 -1.54133300
C -1.89244700 2.36632700 1.43432000 E= -918.29472 H
H -0.46995900 1.19505100 2.54108500 C -0.39204300 0.60683400 0.23988700
C -2.55453900 2.56296800 0.22327000 C 3.01837900 0.84200600 1.96938600
H -2.80352300 1.84933200 -1.80053600 O -0.98395500 0.64180500 -0.84714900
H -2.08310900 3.02602200 2.27581200 O 3.60182200 0.86979200 3.06119700
H -3.26564800 3.37619500 0.11520400 O 3.77062000 0.88731100 0.75055700
C 3.29386200 1.89351500 1.26281900 O -1.12448100 0.37253800 1.44953900
C 2.97702800 3.09454800 1.88450500 C -2.48940500 0.56963200 1.45979400
S-38 C -3.08746000 1.70859500 0.90627100
C -3.26551300 -0.37904300 2.13231200
C -4.46628200 1.88486100 1.02821200
H -2.47811600 2.44275300 0.39152500 E= -918.88744 H
C -4.64302500 -0.18666900 2.25510700 C 1.78174400 2.85663200 -3.04031900
H -2.78158500 -1.25421900 2.55607100 H 1.45951600 3.76890600 -3.53427300
C -5.25098700 0.94249500 1.70025500 C 0.46699600 0.83650700 -2.08978100
H -4.92841100 2.76981300 0.59855900 C 2.91715200 2.92843300 -2.27010900
H -5.24040500 -0.92518300 2.78300600 O 0.43537700 -0.37179300 -1.97355400
H -6.32334300 1.08890200 1.79203900 O 3.70898100 3.84764300 -1.98581000
C 5.08346700 1.30949200 0.78572200 O 3.25582100 1.56637400 -1.72205100
C 6.00689300 0.58223600 0.02889700 O -0.06289600 1.68767600 -1.14205100
C 5.48254300 2.46386200 1.47057400 C -0.62015700 1.14381200 0.02118900
C 7.33360300 1.01123300 -0.04512900 C 0.13979900 0.36920700 0.89727500
H 5.67547100 -0.30875500 -0.49633500 C -1.94098500 1.48090300 0.30975200
C 6.81335600 2.87710000 1.39592000 C -0.44419400 -0.07344400 2.08471100
H 4.75865600 3.02622400 2.04940500 H 1.16872600 0.12936700 0.65723800
C 7.74468300 2.15653900 0.64150300 C -2.51260400 1.03403600 1.50350400
H 8.04615500 0.44415200 -0.63810600 H -2.50414400 2.08819300 -0.39229300
H 7.12161500 3.77319200 1.92810600 C -1.76772100 0.25526000 2.39228800
H 8.77818000 2.48632400 0.58803300 H 0.14392600 -0.67304900 2.77392900
C 1.00078800 0.73254600 0.47664600 H -3.54074600 1.29717100 1.73550200
H 1.60122400 0.84255000 -0.42067800 H -2.21363600 -0.09051700 3.32035100
C 1.62475400 0.72523200 1.73166500 C 3.40989100 1.43690000 -0.37967700
H 1.02333000 0.62291400 2.62922200 C 3.02775200 2.41631700 0.55481900
S-39 C 3.93090900 0.21523700 0.08267200 C -4.25438600 0.58876600 2.57098700
C 3.16088700 2.16071000 1.92053900 H -2.31640800 1.45591600 3.01371900
H 2.62301900 3.35962300 0.20775300 C -4.41773000 -0.58441700 0.46065500
C 4.05062100 -0.02760900 1.45031300 H -2.60478900 -0.62038600 -0.73266100
H 4.21803700 -0.53908000 -0.64476100 C -5.00567300 -0.14573100 1.64929800
C 3.66811400 0.94299300 2.38239400 H -4.70768700 0.93027000 3.49697900
H 2.85171500 2.92355200 2.63108100 H -4.99779700 -1.15668400 -0.25739800
H 4.44289500 -0.98357000 1.78850800 H -6.04578800 -0.37739700 1.85861600
H 3.76131000 0.75214100 3.44758900 C 4.97232200 1.16186800 1.13191400
C 1.00159700 1.59318200 -3.29308500 C 5.77512400 0.51727100 2.06645400
H 1.55475700 0.83528200 -3.86367000 C 5.49782200 1.74216800 -0.01864800
H 0.11296500 1.83800400 -3.89237900 C 7.15168500 0.45213600 1.83709700
H 5.32702000 0.07564100 2.95097300
C 6.87530400 1.67257800 -0.23425000
H 4.83909800 2.23522000 -0.72659900 E= -919.389414 H C 7.70256900 1.02909400 0.69050900 C -0.61729600 1.93752000 0.47194100 H 7.79073800 -0.04981300 2.55766800 C 2.98497200 2.32173900 1.74991600 H 7.30020100 2.12079100 -1.12766900 O -1.41176400 2.82426100 0.24664900 H 8.77313800 0.97626700 0.51616700 O 3.60434200 3.32996600 2.01003100 C 0.88597800 2.04536100 0.39170400 O 3.57600000 1.15462700 1.33257100 H 1.28816300 1.16231300 -0.11094600 O -0.98347300 0.67491100 0.86968400 H 1.12975100 2.93709900 -0.18855500 C -2.35296300 0.44232900 1.11743400 C 1.48627700 2.15320200 1.81668000 C -2.91619700 0.88781200 2.30953700 H 1.25435000 1.24675400 2.38309400 C -3.07998500 -0.28945900 0.18536500 H 1.07431200 3.01930300 2.33699600
S-40 C 5.90304600 0.34936300 0.39783400
C 5.67676100 2.67657700 1.06668900
C 7.28978600 0.49420800 0.35015500
E= -1837.47196 H H 5.43659500 -0.60066800 0.15910100
C 0.97617100 1.08323100 0.54233600 C 7.06222000 2.82445200 1.02353600
H 1.53438800 1.12363700 -0.38654800 H 5.04184400 3.51360000 1.33657400
C 1.58469000 1.16513900 1.73456100 C 7.85049500 1.73038100 0.66664000
H 1.02550200 1.13525700 2.66328200 H 7.91966700 -0.34359800 0.07290800
C -0.48534200 0.95140300 0.36440600 H 7.51866300 3.77848400 1.26254500
C 3.04437200 1.31446100 1.91280100 Cl -7.04008700 0.40614400 1.64689800
O -1.03691800 0.96385000 -0.71838600 Cl 9.59523100 1.91694600 0.61279100
O 3.58168600 1.44152100 2.99539000
O 3.72164900 1.28054200 0.72147900
O -1.14496700 0.80288800 1.55672600
C -2.54899600 0.71330300 1.51916700 E= -1838.04306 H
C -3.31140100 1.84422600 1.24338400 C 1.62667500 2.62674100 -2.91334100
C -3.13251100 -0.50768300 1.83610800 H 1.41747400 3.55154300 -3.43844900
C -4.70162800 1.74978500 1.28147800 C 0.16564600 0.69576600 -2.16046100
H -2.82844400 2.78569600 1.00446100 C 2.57548100 2.71062300 -1.83152000
C -4.52361800 -0.60563300 1.87853000 O -0.05445200 -0.48719400 -2.05918100
H -2.51028600 -1.37083200 2.04817500 O 3.12980200 3.72794500 -1.43893500
C -5.28922200 0.52485800 1.59793300 O 2.79817000 1.45633900 -1.26948800
H -5.31581700 2.61789900 1.06977700 O -0.30356000 1.64246500 -1.28236800
H -4.99967600 -1.54818100 2.12468500 C -1.00264700 1.20956100 -0.14151200
C 5.11920000 1.44010700 0.75554000 C -0.34164800 0.50870600 0.86361100
S-41 C -2.33705500 1.58040700 -0.02119600
C -1.03740800 0.16773900 2.02208600
H 0.70173100 0.23729200 0.75103100
C -3.03606100 1.24441000 1.13851400 E= -1147.30225 H
H -2.82406600 2.12776200 -0.82142000 C 0.90798300 1.38553800 0.54978800
C -2.37601800 0.54092500 2.14467400 H 1.40589200 1.41059600 -0.41333400
H -0.54127900 -0.37621400 2.81809300 C 1.59244100 1.50017800 1.69737900
H -4.07664600 1.52681500 1.25243500 H 1.09433400 1.48444100 2.66066900
C 3.51502600 1.36240300 -0.07492800 C -0.56064800 1.23095800 0.46762600
C 3.13040100 2.08359700 1.05491500 C 3.06052200 1.66372400 1.77702800
C 4.56550700 0.45040500 -0.03206800 O -1.17287600 1.20128700 -0.58350400
C 3.81808600 1.89156500 2.25129500 O 3.66252400 1.81110300 2.82409600
H 2.29921200 2.77759300 1.00695000 O 3.65755000 1.62029000 0.54864300
C 5.25381600 0.25226300 1.16500200 O -1.14349000 1.11809800 1.69864500
H 4.83889600 -0.10237400 -0.92487900 C -2.55110000 1.00965500 1.75287500
C 4.87283300 0.97914000 2.29135000 C -3.35455000 2.10402700 1.43553000
H 3.53138400 2.44174900 3.14071400 C -3.09864900 -0.18193300 2.20365900
H 6.07314800 -0.45629000 1.21522000 C -4.73298500 1.99156200 1.56785400
C 0.93897600 1.36199900 -3.29290200 H -2.90605100 3.02988700 1.09051900
H 1.65352700 0.61292500 -3.65408600 C -4.48547100 -0.29779100 2.34155400
H 0.22276800 1.54752200 -4.10042000 H -2.45092100 -1.01794200 2.44823900
Cl -3.24994100 0.11633000 3.60711000 C -5.30652000 0.79105400 2.01947000
Cl 5.73687100 0.73732500 3.80100300 H -5.38095000 2.82855700 1.32661100
H -4.90610700 -1.23134700 2.69628900
C 5.06185100 1.77184500 0.49513900
S-42 C 5.82932600 0.66017100 0.18233300 H 1.21929000 3.56944000 -3.46830600
C 5.64081100 3.02667900 0.67680600 C 0.23886800 0.62156800 -2.21022400
C 7.21433800 0.79179400 0.04465600 C 2.44826700 2.86882800 -1.84567700
H 5.35289700 -0.30536500 0.04458500 O 0.11773100 -0.57683800 -2.10672200
C 7.01748500 3.16135500 0.54277300 O 2.87707400 3.94768900 -1.45392400
H 5.02131700 3.88460000 0.91757200 O 2.79916300 1.65450800 -1.27473200
C 7.81189500 2.04656600 0.22611400 O -0.33258500 1.52921700 -1.35909000
H 7.80627500 -0.08192300 -0.20137900 C -1.04156000 1.03393700 -0.24224900
H 7.49344800 4.12784600 0.67711800 C -0.35010700 0.47817500 0.83354800
O -6.66929700 0.78334500 2.11358400 C -2.41927000 1.18922300 -0.21229300
O 9.15224400 2.28582600 0.11365200 C -1.06022900 0.07011600 1.95559100
C -7.29730200 -0.42966400 2.56977100 H 0.72832100 0.36921200 0.79226700
H -8.36785900 -0.22197100 2.56034700 C -3.13740100 0.78312300 0.91662200
H -7.07610300 -1.26463700 1.89498400 H -2.93357700 1.62772600 -1.06168500
H -6.97802500 -0.67733800 3.58866800 C -2.45664000 0.21965800 2.00440900
C 9.99962600 1.17262600 -0.22844200 H -0.54543400 -0.36538600 2.80646700
H 11.00883600 1.58239200 -0.28184200 H -4.21333100 0.91034600 0.93347000
H 9.95592600 0.39493900 0.54293200 C 3.57023300 1.65093100 -0.10298500
H 9.71909900 0.75143000 -1.20068000 C 3.13143200 2.29842400 1.05403500
C 4.73895100 0.90154200 -0.10291300
C 3.88251400 2.19341700 2.21798100
H 2.21007800 2.86994300 1.04330800
C 5.49577200 0.79052100 1.06735300
E= -1147.87262 H H 5.05884400 0.40155200 -1.01187600
C 1.53151100 2.67510100 -2.94164800 C 5.06890200 1.44076900 2.23252800
S-43 H 3.55786000 2.68573500 3.12963200 C 3.03703800 1.33762800 1.91394900
H 6.40498600 0.20118100 1.05492400 O -1.03428100 1.00302600 -0.73386200
C 0.99779100 1.33896400 -3.32308100 O 3.57041600 1.47500200 2.99650900
H 1.80136000 0.65815500 -3.62699600 O 3.72219400 1.28574600 0.72573500
H 0.30758400 1.43142000 -4.16847700 O -1.14604200 0.80212500 1.53786800
O -3.05950400 -0.21059600 3.15229700 C -2.54692300 0.71135500 1.49996100
O 5.73325300 1.39921600 3.42663900 C -3.31069100 1.84363500 1.23246300
C -4.48963500 -0.06893900 3.24582200 C -3.12441800 -0.51603500 1.80737100
H -4.75729900 -0.47482600 4.22195700 C -4.69883300 1.74009100 1.27130100
H -4.78365500 0.98558700 3.19048800 H -2.82779000 2.78652900 1.00046400
H -4.99299800 -0.63975400 2.45711000 C -4.51296000 -0.61337100 1.84657700
C 6.94195300 0.61872900 3.48603700 H -2.49642000 -1.37681000 2.01029700
H 7.29849200 0.71534700 4.51218700 C -5.29566400 0.51255900 1.57362500
H 6.73933600 -0.43507300 3.26248600 H -5.31009200 2.61196800 1.06535400
H 7.69660900 1.01078500 2.79439000 H -4.98127300 -1.56277200 2.08321300
C 5.11736400 1.43937200 0.76487800
C 5.89546600 0.33686200 0.42809500
C 5.67728500 2.67834700 1.06288200
C 7.28051100 0.47755700 0.39108200
H 5.42173300 -0.61237800 0.20218800 E= -1592.62823 H C 7.06262800 2.81261800 1.02603300 C 0.97658400 1.10741100 0.53308400 H 5.04264900 3.52002100 1.31741500 H 1.53870900 1.14951800 -0.39334400 C 7.85997000 1.71258300 0.69555800 C 1.57863100 1.18881900 1.72855500 H 7.90273800 -0.37243300 0.13240300 H 1.01517700 1.15972100 2.65468500 H 7.51759000 3.76967100 1.25655800 C -0.48371100 0.97558800 0.34844600
S-44 C -6.79139300 0.40490600 1.65959400 C -2.98285300 1.26122500 1.15603200
C 9.35169600 1.86903200 0.61664200 H -2.78633700 2.16944100 -0.79690600
F -7.43291800 1.35225200 0.92346500 C -2.33240900 0.52289700 2.14769100
F -7.24933000 0.54868800 2.94420400 H -0.49588300 -0.43453000 2.76307400
F -7.25378100 -0.80407800 1.23235300 H -4.01559700 1.56539100 1.28601900
F 9.82107200 2.86076000 1.42206300 C 3.49230800 1.38020200 -0.08750300
F 9.77532100 2.17815600 -0.65057200 C 3.10029600 2.11791000 1.02857700
F 10.01704300 0.73241700 0.96535200 C 4.52854700 0.44991400 -0.02304800
C 3.76847100 1.92231400 2.23476800
H 2.27964200 2.82207700 0.96034200
C 5.18985800 0.25683600 1.18519300
H 4.80343100 -0.11274400 -0.90883700 E= -1593.20023 H C 4.81206200 0.99668800 2.31135000 C 1.62444000 2.62759900 -2.94458100 H 3.46947500 2.48713900 3.11060100 H 1.41337800 3.54732500 -3.47775400 H 5.99756900 -0.46543100 1.25007800 C 0.18424800 0.68523200 -2.18204200 C 0.94564000 1.35645500 -3.31858500 C 2.56729300 2.72473500 -1.85929800 H 1.66490900 0.61325800 -3.68285900 O -0.02417700 -0.49859700 -2.07474300 H 0.22404400 1.53478300 -4.12290000 O 3.11317500 3.74589600 -1.46789400 C -3.04924900 0.18038600 3.42184900 O 2.80075800 1.47121800 -1.29272300 C 5.53904500 0.75717100 3.60192100 O -0.29529000 1.63166900 -1.30551000 F -2.68246500 -1.03587000 3.91623900 C -0.97731000 1.20147600 -0.15750600 F -2.79481400 1.08333100 4.42243900 C -0.31156800 0.47247600 0.82577200 F -4.40185000 0.15270600 3.27618000 C -2.30093100 1.60166700 -0.01046100 F 5.38656300 -0.52803600 4.05103500 C -0.99852900 0.13251400 1.98681800 F 6.88886900 0.94566400 3.48055200 H 0.72309900 0.18124700 0.68888600
S-45 F 5.12489200 1.56789300 4.60988300 C -5.27351300 2.70855200 0.35051600
H -5.13699100 1.47822100 2.14229200
H -5.11613200 0.56897000 0.63103700
H -5.03206100 3.66215400 -1.59172800
H -5.05271100 1.89951800 -1.64389900 E= -925.318377 H H -6.36896300 2.68655400 0.30667700 C 0.97021500 0.66132400 -0.18677300
H -4.99121800 3.62178400 0.89285900 H 1.55269000 -0.25386600 -0.20362400 C 5.19920100 1.01575000 -0.26688400 C 1.56343400 1.86356500 -0.15852900
C 5.74718800 1.03689200 1.15760900 H 0.98070700 2.77844600 -0.13460100 C 5.68826200 -0.19185000 -1.05563000 C -0.49834800 0.45163100 -0.19795500
H 5.45365800 1.94533200 -0.78523900 C 3.03192600 2.07394400 -0.16193200
C 7.28515500 1.01727600 1.12789000 O -0.99854900 -0.66577900 -0.18380200
H 5.37410700 0.15110700 1.68770600 O 3.53149500 3.19094500 -0.11978800 H 5.37886100 1.92375000 1.68360100 O 3.72699700 0.92320400 -0.23064000
C 7.22588000 -0.21166300 -1.08539300 O -1.19262500 1.60412700 -0.23921400 H 5.31588900 -1.10479700 -0.57329900 C -2.66490000 1.51424900 -0.27739000
H 5.27934400 -0.15932400 -2.07134100 C -3.21327300 1.46196300 1.14620300 C 7.80932300 -0.18884700 0.33491000 C -3.15201700 2.73998600 -1.03892900
H 7.67072300 1.00095600 2.15347300 H -2.92051500 0.59681100 -0.81645200 H 7.64892500 1.94378000 0.66299700 C -4.75123000 1.48434000 1.11668100
H 7.56958200 -1.09920700 -1.62842100 H -2.83892300 2.33484100 1.69645500 H 7.58818800 0.66428600 -1.64075200 H -2.84647900 0.56279600 1.65200500
H 8.90476000 -0.16450900 0.29196000 C -4.68951000 2.76223200 -1.06875300
H 7.52802600 -1.11426000 0.85669800 H -2.77878800 3.64131200 -0.53578500
H -2.74262600 2.72998600 -2.05490700
S-46 H -5.28170100 2.29754700 -0.23504700
H -4.59198800 0.71625800 0.13124000
H -4.71946900 2.06888600 2.20725100 E= -925.886664 H H -3.79961900 3.36982900 1.44745700 C 1.72078900 2.58067300 -2.16937600 C 4.62854500 1.20888400 -0.34078500 H 1.23148200 3.54024100 -2.29663300 C 4.17077900 1.06097700 1.10954100 C 0.05052200 0.79645300 -1.70807900 C 5.39275000 -0.01608600 -0.82770700 C 2.92315100 2.58752600 -1.36231500 H 5.23404500 2.11369600 -0.45563600 O 0.12937600 -0.29293300 -1.17275500 C 5.37687000 0.78925900 2.02415800 O 3.40963000 3.60861900 -0.86981700 H 3.46530400 0.22153600 1.16424900 O 3.45438200 1.34396500 -1.21101300 H 3.63917300 1.96559600 1.42251300 O -0.93568600 1.68915200 -1.50971500 C 6.59901300 -0.28774400 0.08672900 C -1.96925100 1.35661200 -0.50588500 H 4.71681000 -0.88102400 -0.81476900 C -1.51019400 1.85263800 0.86191400 H 5.71599000 0.13868200 -1.86315800 C -3.25865100 2.02660900 -0.96051100 C 6.16373800 -0.44136500 1.55125400 H -2.08197400 0.26875000 -0.50009600 H 5.03170700 0.65278500 3.05545000 C -2.61511500 1.61992400 1.90631500 H 6.03848100 1.66640400 2.02139800 H -1.28965500 2.92527300 0.78678300 H 7.12191800 -1.18804300 -0.25520300 H -0.58640500 1.34006100 1.15103800 H 7.31062700 0.54554300 0.00578900 C -4.36418700 1.78995800 0.08316300 H 7.04072400 -0.59749600 2.19068600 H -3.08005000 3.10378100 -1.07320900 H 5.53092900 -1.33459400 1.64888500 H -3.55635100 1.63252100 -1.93845600 C 1.08069100 1.34783800 -2.70711100 C -3.93277400 2.27933900 1.47306100 H 1.80875600 0.55759200 -2.88772600 H -2.28925000 2.01022000 2.87720100 H 0.54280900 1.57974900 -3.63286900 H -2.77257700 0.53993300 2.03170600
S-47 C -5.38977000 3.28533300 -2.76541800
H -6.13225900 2.49978000 -2.87105500
C -4.16145900 3.11518800 -3.37601900
(DME) H -3.97496500 2.20291000 -3.93032500
E= -2135.34135513 H C -3.15066800 4.11211800 -3.27797000
C -9.49623600 4.37722000 -4.01545200 C -3.46337800 5.28329800 -2.53454200
H -9.46227500 3.32493500 -4.26263600 H -2.72672200 6.06948200 -2.41866300
C -8.46174600 5.33253500 -4.26587700 C -4.70225000 5.43895900 -1.93928900
H -7.50366000 5.12670900 -4.72370700 H -4.89156800 6.34620500 -1.37247800
C -8.88297200 6.58626300 -3.72409900 Co -8.82427900 5.16792600 -2.26391400
H -8.30383100 7.49934200 -3.71117000 N -1.93229600 3.94876400 -3.87086000
C -10.18613100 6.40948300 -3.15244100 C -0.89508200 4.96642900 -3.71952800
H -10.75836600 7.16615800 -2.63359000 H -0.63914500 5.12010100 -2.66363100
C -10.56563100 5.04513700 -3.33431900 H -0.00125200 4.63549200 -4.24713800
H -11.47595700 4.58436400 -2.97643600 H -1.21422300 5.92577100 -4.14530200
C -7.53111100 5.84555700 -0.84570400 C -1.62899200 2.72896900 -4.61564000
H -7.04949000 6.81259000 -0.87419200 H -1.67450500 1.84369500 -3.96837700
C -8.81687900 5.58396100 -0.28267400 H -2.32861300 2.58930300 -5.44865200
H -9.46317700 6.31189200 0.18827500 H -0.62128500 2.80914800 -5.02275200
C -9.12101800 4.20506000 -0.50866400
H -10.03705800 3.69894300 -0.23582100
C -8.02253000 3.62350500 -1.21188700
H -7.97509800 2.59889600 -1.55358100
C -6.99386500 4.62107900 -1.39087500
C -5.70152500 4.44846800 -2.03145400
S-48 H -0.46253000 4.26771300 6.95664000
C -5.51319900 4.41045600 1.69942000
C -6.44653100 3.67348700 2.43224600
C -5.52486800 5.80812400 1.71405900
C -7.41359500 4.36552900 3.16598400
(DME) H -6.42281500 2.59340900 2.43136900
E= -3054.29828896 H C -6.49438100 6.47996000 2.45398100
C -3.18718400 2.33695000 -0.21204700 H -4.77134100 6.34715700 1.14900900
H -3.06373700 1.35471600 -0.65240800 C -7.44857500 5.76061700 3.17863700
C -1.64579700 3.94227300 1.01600900 H -8.14387200 3.79837000 3.73623800
C -4.44986400 2.58116900 0.43794300 H -6.50206300 7.56613300 2.46379500
O -1.23834200 5.06769000 1.18062000 H -8.20704500 6.28290600 3.75410100
O -5.37664500 1.78462700 0.51729200 C -2.10886900 3.35812400 -0.31386800
O -4.46582600 3.86437500 0.96431700 H -2.43503600 4.21217100 -0.91973200
O -1.70822600 2.99434800 2.00365200 H -1.22772700 2.92941700 -0.80347900
C -1.35925300 3.39074000 3.31342200 C -9.12263600 3.79667400 -4.20562000
C -2.29930000 4.05244900 4.09700400 H -8.87062400 2.78231700 -4.48331100
C -0.10760500 3.03585700 3.80202800 C -8.32835200 4.95822000 -4.45921600
C -1.96644000 4.36826400 5.41517600 H -7.36419600 4.97483800 -4.94857200
H -3.26783300 4.31206700 3.68246700 C -8.99139800 6.07967600 -3.87026500
C 0.21139100 3.35571400 5.12353200 H -8.62410300 7.09659200 -3.85148400
H 0.59819800 2.51940500 3.15924100 C -10.20460700 5.61344600 -3.26553200
C -0.71465800 4.02129700 5.92946700 H -10.90868800 6.21686600 -2.70938500
H -2.68986300 4.88446600 6.03954500 C -10.28576300 4.20317000 -3.47291200
H 1.18519500 3.08332200 5.51986500 H -11.06118200 3.54814300 -3.10030500
S-49 C -7.33123700 5.56794500 -1.11476600 C -1.12004200 3.10321200 -4.89167100
H -6.99147900 6.59127900 -1.18083300 H -0.94275500 2.35730700 -4.10502500
C -8.53738200 5.14414500 -0.48095800 H -1.80989600 2.67622200 -5.62874300
H -9.25260400 5.78710200 0.01274300 H -0.17427900 3.31426000 -5.39026200
C -8.65293300 3.73114800 -0.66027700
H -9.47300800 3.10973400 -0.32790300
C -7.51943500 3.28928800 -1.40488200
H -7.34536200 2.27205300 -1.72240600
C -6.65545700 4.41631100 -1.66374800
C -5.38229700 4.40222600 -2.36490600
C -4.87802200 3.22460500 -2.95531800 (DME)
H -5.44894900 2.30312000 -2.89723900 E= -3054.43858722 H
C -3.66114800 3.19886200 -3.61270700 C -5.12569300 1.93106600 0.62529100
H -3.31751400 2.26223300 -4.03516100 H -5.53218000 0.92550700 0.62823000
C -2.86058900 4.36867400 -3.71571900 C -2.76160300 2.86756100 1.05287400
C -3.36814200 5.55684800 -3.12109400 C -5.90283400 2.92050800 1.19251300
H -2.79286200 6.47431100 -3.15851600 O -1.91201500 3.66204200 0.71047100
C -4.59044700 5.56323100 -2.47259000 O -7.03976200 2.90498300 1.69640800
H -4.92976500 6.49371000 -2.02734500 O -5.21487600 4.22450400 1.07619100
Co -8.57734400 4.67843200 -2.45148200 O -2.91144700 2.44844100 2.36026700
N -1.64709300 4.34906700 -4.34089300 C -2.12399400 3.02723800 3.35915200
C -0.80166000 5.54073300 -4.34607700 C -2.12739400 4.40349600 3.58698100
H -0.54305600 5.85187000 -3.32551900 C -1.40646300 2.15999900 4.18059400
H 0.11844200 5.31247800 -4.88339800 C -1.39424100 4.91044400 4.66008000
H -1.29954200 6.37632900 -4.85213400 H -2.70180800 5.06019800 2.94534800
S-50 C -0.68001400 2.68017500 5.25358000 H -8.88886200 6.29032500 -3.99555300
H -1.42772300 1.09330800 3.97951100 C -10.18143700 4.53185100 -3.46884700
C -0.67012100 4.05545800 5.49544500 H -10.96966200 4.97559800 -2.87638600
H -1.39832200 5.98089700 4.84589100 C -10.01699100 3.13964900 -3.74275900
H -0.12303300 2.00676900 5.89912000 H -10.66167500 2.34300900 -3.39710000
H -0.10550800 4.45860400 6.33128900 C -7.36536700 4.86893300 -1.29354600
C -5.33805900 5.15505900 2.06172500 H -7.26930900 5.94468900 -1.25771100
C -5.66782300 4.85304600 3.39295400 C -8.42422400 4.11881500 -0.70406700
C -5.02374500 6.47746900 1.71051700 H -9.25727200 4.52617400 -0.14907700
C -5.67674800 5.87050200 4.34759400 C -8.21498300 2.74492100 -1.02155700
H -5.89874500 3.83229600 3.67033900 H -8.85640800 1.92182200 -0.74135400
C -5.02775400 7.48142500 2.67783100 C -7.00761800 2.64337500 -1.77135600
H -4.75500800 6.69348000 0.68044500 H -6.60309600 1.73025000 -2.18172500
C -5.35871800 7.18726800 4.00394600 C -6.45561500 3.96168800 -1.94773500
H -5.92480000 5.62387900 5.37715100 C -5.22414500 4.30801000 -2.64256500
H -4.76922600 8.49825900 2.39240400 C -4.50851300 3.35465200 -3.39308400
H -5.36369300 7.96957800 4.75764700 H -4.89273600 2.34304900 -3.48774600
C -3.72505400 2.14953900 0.12330100 C -3.31492600 3.66359800 -4.02202500
H -3.67470800 2.72023500 -0.81201600 H -2.80406000 2.88864200 -4.58160800
H -3.26015800 1.17549200 -0.08552900 C -2.75812600 4.96802200 -3.93266400
C -8.82178800 2.97598500 -4.52074100 C -3.48305700 5.93212400 -3.18288400
H -8.41342800 2.03549800 -4.86488000 H -3.09716800 6.93856900 -3.07017500
C -8.24573000 4.26641500 -4.72048400 C -4.67633000 5.60235100 -2.56277500
H -7.31557400 4.47695800 -5.23097200 H -5.18298200 6.36746000 -1.98209700
C -9.07760600 5.22722600 -4.05924400 Co -8.39274500 3.84836600 -2.72067800
S-51 N -1.57272900 5.27996500 -4.54110400 C -1.10490100 0.13315600 2.00126000
C -1.01567800 6.62366500 -4.42326600 H 0.63982600 0.13640100 0.71969400
H -0.78032800 6.87272400 -3.37990200 C -3.03900800 1.31015300 1.14985200
H -0.09659300 6.67369200 -5.00715000 H -2.79197600 2.22072400 -0.80441600
H -1.71299000 7.37612900 -4.81224000 C -2.42708600 0.55843300 2.15481400
C -0.81320500 4.25165800 -5.24495600 H -0.62402400 -0.44923000 2.78178200
H -0.56143700 3.41517700 -4.58044000 H -4.06595300 1.64436100 1.26500800
H -1.37244200 3.85871400 -6.10399200 H -2.97769100 0.30593500 3.05622100
H 0.11446800 4.69150500 -5.61099600 C 3.54190800 1.36457600 -0.07432100
C 3.12305000 2.04652100 1.06721700
C 4.63288700 0.50073300 -0.05093600
C 3.82558300 1.85675300 2.25711600 (DME) H 2.26169800 2.70379400 1.02396600 E= -918.74707 H C 5.32436800 0.31744400 1.14822900 C 1.61874300 2.60362300 -2.90424200 H 4.92651600 -0.01847500 -0.95787100 H 1.38555000 3.52951200 -3.41741700 C 4.92526100 0.99532900 2.30171500 C 0.15132900 0.67180600 -2.15806200 H 3.50688300 2.38178700 3.15303700 C 2.56782000 2.70114000 -1.82175600 H 6.17555500 -0.35672200 1.17656600 O -0.08832600 -0.50788700 -2.06999800 H 5.46582800 0.85120100 3.23252000 O 3.09778600 3.72978300 -1.42706800 C 0.94801500 1.32996600 -3.28333900 O 2.81663900 1.45008900 -1.26894500 H 1.67340400 0.57852300 -3.61653100 O -0.30750600 1.62271200 -1.28228700 H 0.24862200 1.49818100 -4.10947400 C -1.02127600 1.20255400 -0.14149800
C -0.38854600 0.45529600 0.84816300
C -2.33554900 1.63682800 -0.01140400
S-52 (DME) H -3.53342900 1.29979800 1.75308900
E= -918.88744 H H -2.19309100 -0.07064600 3.34262500
C 1.78198000 2.86455800 -3.02912300 C 3.41961000 1.44212100 -0.39983100
H 1.42948700 3.77592400 -3.50337200 C 3.02545100 2.41538600 0.53767100
C 0.48795800 0.82699900 -2.07804900 C 3.92426000 0.21341700 0.06544200
C 2.92742900 2.95568200 -2.27605100 C 3.13064800 2.14759900 1.90271900
O 0.47857900 -0.37955800 -1.95063400 H 2.63284600 3.36308800 0.18944100
O 3.70808400 3.87989500 -1.99517300 C 4.01687000 -0.04078700 1.43260500
O 3.29724000 1.58527500 -1.73965300 H 4.21901200 -0.53759000 -0.66230700
O -0.07558300 1.67776500 -1.14530800 C 3.62231500 0.92394100 2.36556300
C -0.62155800 1.13988400 0.02181000 H 2.81086800 2.90638100 2.61319200
C 0.14484000 0.37534600 0.90149400 H 4.39661500 -1.00243500 1.77008400
C -1.94208400 1.47427300 0.31709800 H 3.69342700 0.72391800 3.43100400
C -0.43140600 -0.05820900 2.09531400 C 1.02631800 1.58675200 -3.27968200
H 1.17404800 0.13879200 0.66043800 H 1.59978000 0.83379600 -3.83642800
C -2.50588700 1.03662300 1.51729800 H 0.14127700 1.81207000 -3.89261900
H -2.51066700 2.07506300 -0.38624300
C -1.75396100 0.26792200 2.40843300
H 0.16414800 -0.64803900 2.78674500
S-53 S7. References
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