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1 Supporting Information For: Highly Fluorinated Ir(III)- 2,2 :6,2 -Terpyridine -Phenylpyridine-X Complexes via Selective C-F Activation: Robust Photocatalysts for Solar Fuel Generation and Photoredox Catalysis Jonathan A. Porras, Isaac N. Mills, Wesley J. Transue, and Stefan Bernhard Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States Synthesis and Characterization of mppy Precursors Synthesis and Characterization of mppy Ligands NMR Spectra of Final Complexes NMR Spectra of Crude Reactions and Derivatizations ESI-MS of Crude Reactions UV-Vis Absorption Spectra TD-DFT Results Computational Emission Energy Modeling Additional Photoredox Catalysis CO 2 Traces Combined Triplet Orbital Diagrams (3a-3c) Expanded Frontier Orbital Diagrams Calculated Molecular Orbitals and Singlet Optimized Geometries S1-S2 S2-S4 S5-S18 S18-S19 S20 S21 S22-S23 S23 S24 S25 S26-S27 S28-S45

2 Synthesis of mppy Precursors. In a typical reaction, the corresponding acetophenone (50 mmol) was dissolved in CHCl 3 (40 ml) and cooled to 0 o C with an ice bath. A solution of Br 2 (1.10 equiv) in CHCl 3 was added and the solution was left to stir for 2 hours at room temperature, at which point the solution became pale orange. The reaction mixture was poured into a 250 ml separatory funnel and was washed with saturated Na 2 S 2 O 3, water, and saturated NaCl. The CHCl 3 was evaporated in-vacuo and the orange oil was suspended in diethyl ether. A solution of pyridine (10 equiv) in diethyl ether was added, which upon addition formed an immediate precipitate. The solution was stirred for 3 hours, at which point the precipitate was filtered and washed with diethyl ether. The product was of sufficient purity to use in the next synthetic step. 1-(2-oxo-2-phenylethyl)pyridine-1-ium bromide. 1 H NMR (300 MHz, DMSO-d 6 ): δ 9.04 (dd, J = 1.23, 6.69 Hz, 2H), 8.75 (m,1h), 8.29 (m, 2H), 8.08 (dd, J = 1.23, 8.34, 2H), 7.80 (m, 1H), 7.69 (m, 2H), 6.54 (s, 2H). 1-(2-(4-fluorophenyl)-2-oxoethyl)pyridine-1-ium bromide. 1 H NMR (300 MHz, DMSO-d 6 ): δ (m, 2H), 8.75 (m, 1H), 8.29 (m, 2H), 8.17 (m, 2H), 7.51 (m, 2H), 6.68 (s, 2H). 19 F NMR ( MHz, DMSO-d 6 ): δ (m, 1F). 1-(2-(2-fluorophenyl)-2-oxoethyl)pyridin-1-ium bromide. 1 H NMR (300 MHz, DMSO-d 6 ): δ (dd, J = 1.10, 6.56 Hz, 2H), 8.75 (t, J = 7.83 Hz, 1H), 8.29 (m, 2H), 8.02 (td, J = 1.80, 7.67 Hz, 1H), 7.85 (m, 1H), 7.52 (m, 2H), 6.37 (d, J = 3.28 Hz, 2H). 19 F NMR ( MHz, DMSOd 6 ): δ (m, 1F). 1-(2-(2,4-difluorophenyl)-2-oxoethyl)pyridin-1-ium bromide. 1 H NMR (300 MHz, DMSOd 6 ): δ (d, J = 5.55 Hz, 2H), 8.75 (t, J = 7.83 Hz, 1H), 8.29 (m, 2H), 8.11 (td, J = 6.70, 8.66 Hz, 1H), 7.62 (ddd, J = 2.40, 9.27, Hz, 1H), 7.37 (td, J = 2.35, 8.47, 8.50 Hz, 1H), 6.50 (d, J = 3.11 Hz, 2H). 19 F NMR ( MHz, DMSO-d 6 ): δ (m, 1H), (m, 1H). S1

3 1-(2-(2,6-difluorophenyl)-2-oxoethyl)pyridin-1-ium bromide. 1 H NMR (300 MHz, DMSOd 6 ): δ (d, J = 5.47 Hz, 2H), 8.75 (t, J = 7.84 Hz, 1H), 8.29 (m, 2H), 7.84 (tt, J = 6.35, 8.45 Hz, 1H), 7.38 (dd, J = 8.54, 9.95 Hz, 2H), 6.28 (s, 2H). 19 F NMR ( MHz, DMSO-d 6 ): δ (dd, J = 6.60, 10.28, 2F). 1-(2-oxo-2-(2,4,6-trifluorophenyl)ethyl)pyridin-1-ium bromide. 1 H NMR (300 MHz, DMSOd 6 ): δ (d, J = 5.50 Hz, 2H), 8.75 (t, J = 7.84 Hz, 1H), 8.29 (m, 2H), 7.53 (m, 2H), 6.27 (s, 2H). 19 F NMR ( MHz, DMSO-d 6 ): δ (m, 1F), (t, J = Hz, 2F). Synthesis of mppy Ligands by Kröhnke Condensation. In a typical reaction, the corresponding acyl pyridinium bromide precursor (40 mmol), methacrolein (1.05 equiv), NH 4 OAc (10 equiv), and methanol (50 ml) were combined and heated to 65 o C overnight. The solution was diluted with a four-fold volume of water and extracted with diethyl ether. The diethyl ether was removed in vacuo, and the crude residue was dissolved in 3 M HCl (Note: at this step some of the more fluorinated mppy ligands may crash out of solution as their HCl salts). The aqueous layer was extracted twice with diethyl ether, after which it was neutralized with solid Na 2 CO 3. The aqueous phase was extracted with diethyl ether, dried with Na 2 SO 4, and solvent was removed in vacuo. The product was then chromatographed on silica gel using 10% EtOAc/Hexanes as the eluent. 5-methyl-2-phenylpyridine (mppy). Yield: 64%. 1 H NMR (500 MHz, CDCl 3 ): δ (m, 1H), 7.98 (m, 2H), 7.62 (d, J = 8.06 Hz, 1H), 7.54 (dd, J = 2.09, 8.07 Hz, 1H), 7.46 (t, J = 7.53 Hz, 2H), 7.39 (t, J = 7.32 Hz, 1H), 2.36 (s, 3H). 13 C NMR ( MHz, CDCl 3 ): δ , , , , , , , , (broad, 2C), , MS (m/z ESI, CH 3 OH) Calculated: [M+H] + Found: [M+H] +. 2-(4-fluorophenyl)-5-methylpyridine (4-Fmppy). Yield: 62%. 1 H NMR (500 MHz, CDCl 3 ): δ (s, 1H), 7.94 (ddd, J = 2.58, 5.30, 8.41 Hz, 2H), 7.57 (m, 2H), 7.13 (m, 2H), 2.36 (s, 3H). 19 F NMR ( MHz, CDCl 3 ): δ (s, 1F). 13 C NMR ( MHz, CDCl 3 ): δ S2

4 (d, J = Hz), , , , (d, 3.09 Hz), , , , , , (d, J = Hz), MS (m/z ESI, CH 3 OH) Calculated: [M+H] + Found: [M+H] +. 2-(2-fluorophenyl)-5-methylpyridine (2-Fmppy). Yield: 74%. 1 H NMR (500 MHz, CDCl 3 ): δ (s, 1H), 7.96 (td, J = 1.79, 7.88 Hz, 1H), 7.68 (dd, J = 2.05, 8.06 Hz, 1H), 7.55 (dd, J = 1.78, 8.07 Hz, 1H), 7.34 (m, 1H), 7.25 (m, 1H), 7.14 (m, 1H), 2.36 (s, 1H). 19 F NMR ( MHz, CDCl 3 ): δ (s, 1F). 13 C NMR ( MHz, CDCl 3 ): δ (d, J = Hz), (d, J = 2.13 Hz), , , , (d, J = 3.07 Hz), (d, J = 8.51 Hz), (d, J = Hz), (d, J = 3.58 Hz), (d, J = 8.82 Hz), (d, J = Hz), MS (m/z ESI, CH 3 OH) Calculated: [M+H] + Found: [M+H] +. 2-(2,4-difluorophenyl)-5-methylpyridine (2,4-dFmppy). Yield: 54%. 1 H NMR (500 MHz, CDCl 3 ): δ (s, 1H), 7.98 (td, J = 6.71, 8.85 Hz, 1H), 7.64 (dd, J = 2.17, 8.07 Hz 1H), 7.56 (dd, J = 1.92, 8.09 Hz, 1H), 6.98 (td, J = 2.39, 8.41 Hz, 1H), 6.89 (ddd, J = 2.50, 8.83, Hz, 1H), 2.37 (s, 3H). 19 F NMR ( MHz, CDCl 3 ): δ (d, J = 8.05 Hz, 1F), (d, J = 8.37 Hz, 1F). 13 C NMR ( MHz, CDCl 3 ): δ (d, J = Hz), (dd, J = 12.00, Hz), (d, J = Hz), , (d, J = 2.42 Hz), , , (d, J = 4.57, 9.61 Hz), (d, J = 9.15 Hz), (dd, J = 3.65, Hz), (dd, J = 25.43, 27.01), MS (m/z ESI, CH 3 OH) Calculated: [M+H] + Found: [M+H] +. 2-(2,6-difluorophenyl)-5-methylpyridine (2,6-dFmppy). Yield: 49%. 1 H NMR (500 MHz, CDCl 3 ): δ (d, J = 1.94 Hz, 1H), 7.59 (dd, J = 1.78, 7.95 Hz, 1H), 7.38 (d, J = 7.91 Hz, 1H), 7.31 (tt, J = 6.30, 8.37 Hz, 1H), 6.98 (td, J =4.23, 8.1 Hz, 1H), 2.38 (s, 3H). 19 F NMR ( MHz, CDCl 3 ): δ (s, 2F). 13 C NMR ( MHz, CDCl 3 ): δ (dd, J = 6.96, Hz), , , , , (t, J = Hz), (t, J = 1.48 Hz), (t, J = Hz), (dd, J = 20.37, 5.91 Hz), MS (m/z ESI, CH 3 OH) Calculated: [M+H] + Found: [M+H] +. S3

5 5-methyl-2-(2,4,6-trifluorophenyl)pyridine (2,4,6-tFmppy). Yield: 58%. 1 H NMR (500 MHz, CDCl 3 ): δ (s, 1H), 7.59 (m, 1H), 7.34 (d, J = 7.93 Hz, 1H), 6.76 (m, 2H), 2.39 (s, 1H). 19 F NMR ( MHz, CDCl 3 ): δ (s, 1F), (d, J = 6.61, 2F). 13 C NMR ( MHz, CDCl 3 ): δ (dt, J = 15.52, 15.52, Hz), (ddd, J = 9.66, 14.92, Hz), , , , , , (m), (m), MS (m/z ESI, CH 3 OH) Calculated: [M+H] + Found: [M+H] +. Synthesis of PFmppy and PFMeOppy. In a typical reaction, K 3 PO 4 (4.0 equiv), 1,10- phenanthroline (10 mol %), corresponding 2-bromopyridine (6.0 mmol), pentafluorobenzene (4.5 equiv), 1:1 DMF/Xylenes (20 ml) were degassed by four cycles of vacuum and argon, at which point CuI (10 mol %) was added. The solution was heated to 120 o C overnight. Once cooled, the reaction was poured into a separatory funnel containing diethyl ether and 1:1 water/nh 4 OH. The aqueous phase was extracted with diethyl ether, and the combined extracts were dried with Na 2 SO 4, and the solvents were removed in vacuo. The crude product was chromatographed on silica gel using 10% EtOAc/Hexanes as the eluent. 5-methyl-2-(perfluorophenyl)pyridine (PFmppy). Yield: 55%. 1 H NMR (500 MHz, CDCl 3 ): δ (s, 1H), 7.66 (dd, J = 2.06, 7.95 Hz, 1H), 7.38 (d, J = 7.93 Hz, 1H), 2.43 (s, 3H). 19 F NMR ( MHz, CDCl 3 ): δ (dd, J = 7.93, Hz, 2F), (t, J = Hz, 1F), (td, J = 7.48, Hz, 2F). 13 C NMR ( MHz, CDCl 3 ): δ , (dm, J = Hz), , (dm, J = Hz), (dm, J = Hz), , , , (m), MS (m/z ESI, CH 3 OH) Calculated: [M+H] + Found: [M+H] +. 5-methoxy-2-(perfluorophenyl)pyridine (PFMeOppy). Yield: 81%. 1 H NMR (500 MHz, CDCl 3 ): δ (d, J = 2.87 Hz, 1H), 7.41 (d, J = 8.60 Hz, 1H), 7.32 (dd, J = 2.96, 8.63 Hz, 1H), 3.92 (s, 3H). 19 F NMR ( MHz, CDCl 3 ): δ (dd, J = 8.10, Hz, 2F), (t, J = Hz, 1F), (td, J = 6.88, Hz, 2F). 13 C NMR ( MHz, CDCl 3 ): δ , (dm, J = Hz), (dm, J = Hz), , , (dm, J = Hz), , , (m), MS (m/z ESI, CH 3 OH) Calculated: [M+H] + Found: [M+H] +. S4

6 Figure S1. 1 H-NMR spectrum (500 MHz) of 2a in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. Figure S2. 19 F-NMR spectrum ( MHz) of 2a in acetone-d 6. S5

7 Figure S3. 13 C-NMR spectrum ( MHz) of 2a in acetone-d 6. Residual solvent signals at 29.8 and Figure S4. 1 H-NMR spectrum (500 MHz) of 2b in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. S6

8 Figure S5. 19 F-NMR spectrum ( MHz) of 2b in acetone-d 6. Figure S6. 13 C-NMR spectrum ( MHz) of 2b in acetone-d 6. Residual solvent signals at 29.8 and S7

9 Figure S7. 1 H-NMR spectrum (500 MHz) of 2c in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. Figure S8. 19 F-NMR spectrum ( MHz) of 2c in acetone-d 6. S8

10 Figure S9. 13 C-NMR spectrum ( MHz) of 2c in acetone-d 6. Residual solvent signals at 29.8 and Figure S10. 1 H-NMR spectrum (500 MHz) of 2d in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. S9

11 Figure S F-NMR spectrum ( MHz) of 2d in acetone-d 6. Figure S C-NMR spectrum ( MHz) of 2d in acetone-d 6. Residual solvent signals at 29.8 and S10

12 Figure S13. 1 H-NMR spectrum (500 MHz) of 2e in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. Figure S F-NMR spectrum ( MHz) of 2e in acetone-d 6. S11

13 Figure S C-NMR spectrum ( MHz) of 2e in acetone-d 6. Residual solvent signals at 29.8 and Figure S16. 1 H-NMR spectrum (500 MHz) of 2f in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. S12

14 Figure S F-NMR spectrum ( MHz) of 2f in acetone-d 6. Figure S C-NMR spectrum ( MHz) of 2f in acetone-d 6. Residual solvent signals at 29.8 and S13

15 Figure S19. 1 H-NMR spectrum (500 MHz) of 3a in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. Figure S F-NMR spectrum ( MHz) of 3a in acetone-d 6. Note: Trace unreacted ligand is present and was removed with subsequent recrystallization. S14

16 Figure S C-NMR spectrum ( MHz) of 3a in acetone-d 6. Residual solvent signals at 29.8 and Figure S22. 1 H-NMR spectrum (500 MHz) of 3b in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. S15

17 Figure S F-NMR spectrum ( MHz) of 3b in acetone-d 6. Figure S C-NMR spectrum ( MHz) of 3b in acetone-d 6. Residual solvent signals at 29.8 and S16

18 Figure S25. 1 H-NMR spectrum (500 MHz) of 3c in acetone-d 6. Residual solvent signals at 2.0 and 2.8 ppm. Figure S F-NMR spectrum ( MHz) of 3c in acetone-d 6. Note: trace unreacted ligand is present but was removed with subsequent recrystallization. S17

19 Figure S C-NMR spectrum ( MHz) of 3c in acetone-d 6. Residual solvent signals at 29.8 and Figure S F-NMR spectrum ( MHz) of crude reaction of 1a with 2,4-dFmppy, showing the production of the C-F activation product (2b), C-H activation product (2d), and the byproducts of the generated HF with the borosilicate glass (BF 3 OH - and BF 4 - ). S18

20 Figure S F-NMR spectrum ( MHz) of crude reaction of 1a with 2-Fmppy, showing the production of the C-H activation product (2c) and the byproducts of the generated HF with the borosilicate glass (BF 3 OH - and BF 4 - ). Figure S30. 1 H-NMR spectrum ( MHz) in DMSO-d 6 of the hydrazone generated from the oxidation products from crude reaction of 1a with 2-Fmppy reacting with 2,4- dinitrophenylhydrazine (DNPH) (red). The spectrum is overlayed with that of the pure hydrazone generated from the reaction of glyoxal with DNPH (blue). Unreacted DNPH indicated. S19

21 Figure S31. ESI-mass spectrum of the crude reaction of 1a with 2,4-dFmppy, showing both the C-F activation product (2b) and the C-H activation product (2d). Spectrum collected with a 50 µm methanol solution. Figure S32. ESI-mass spectrum of the crude reaction of 1a with 2-Fmppy, showing both the C-F activation product (2a) and the C-H activation product (2c). Spectrum collected with a 50 µm methanol solution. S20

22 Figure S33. UV-Vis absorption spectra of chloro complexes 2a (black), 2b (orange), 2c (cyan), 2d (green), 2e (yellow), and 2f (blue). All spectra were recorded at room temperature using 10 µm acetonitrile solutions. Figure S34. UV-Vis absorption spectra of cyano complexes 3a (orange), 3b (pink), and 3c (black dashed). All spectra were recorded at room temperature using 10 µm acetonitrile solutions. S21

23 Figure S35. Experimental (purple) and Calculated (black dashed) UV-Vis absorption spectra of 2c. Calculated spectra were determined from Gaussian 09 TD-DFT calculations using Gaussum software with a fwhm = 4000 cm -1. Oscillator strengths are included as vertical lines. Figure S36. Experimental (green) and Calculated (black dashed) UV-Vis absorption spectra of 2f. Calculated spectra were determined from Gaussian 09 TD-DFT calculations using Gaussum software with a fwhm = 4000 cm -1. Oscillator strengths are included as vertical lines. S22

24 Figure S37. Experimental (orange) and Calculated (black dashed) UV-Vis absorption spectra of 3c. Calculated spectra were determined from Gaussian 09 TD-DFT calculations using Gaussum software with a fwhm = 4000 cm -1. Oscillator strengths are included as vertical lines. Figure S38. Relationship between experimental emission energy and energy difference between the total energies of singlet and triplet excited states at the optimized triplet geometry. S23

25 Figure S39. Combined CO 2 evolution traces using 2b (solid), 3a (dashed), and [Ir(dF(CF 3 )ppy) 2 (dtbbpy)]pf 6 (dot-dashed). 1-naphthalene acetic acid (blue), 4-biphenylacetic acid (gold), diphenylacetic acid (black), cyclohexylcarboxylic acid (green), 3,3,3- triphenylpropionic acid (pink). Figure S40. CO 2 evolution traces using 2b with diphenylacetic acid at varying catalyst concentrations. 0.1 mol % (black), 0.05 mol % (orange), mol % (blue), mol % (green), mol % (yellow). S24

26 Figure S41. Triplet frontier orbital diagrams of 3a-3c. Increasing fluorination leads to a decrease in metal character in the triplet state, most notably in the LSOMOs. S25

27 -3 LUMO+6-4 LUMO+2-5 LUMO+5 LUMO Energy (ev) -6-7 LUMO+1 E = 3.08 ev -8 HOMO-1 HOMO -9 HOMO-4-10 HOMO-3 Figure S42. Expanded Frontier Orbital diagram of 2c. HOMO-6 S26

28 -3 LUMO+6-4 LUMO+2-5 LUMO+5 LUMO Energy (ev) -6-7 LUMO+1 E = 3.52 ev -8 HOMO-1 HOMO -9 HOMO-3-10 HOMO-2 Figure S43. Expanded Frontier Orbital Diagram of 3c. HOMO-4 S27

29 DFT Results for 2a SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S28

30 Singlet Optimized Coordinates for 2a: Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S29

31 DFT Results for 2b SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S30

32 Singlet Optimized Coordinates for 2b: Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S31

33 DFT Results for 2c SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S32

34 Singlet Optimized Coordinaes for 2c: Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S33

35 DFT Results for 2d SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S34

36 Singlet Optimized Coordinates for 2d Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S35

37 DFT Results for 2e SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S36

38 Singlet Optimized Coordinates for 2e Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S37

39 DFT Results for 2f SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S38

40 Singlet Optimized Coordinates for 2f Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S39

41 DFT Results for 3a SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S40

42 Singlet Optimized Coordinates for 3a Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S41

43 DFT Results for 3b SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S42

44 Singlet Optimized Coordinates for 3b Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S43

45 DFT Results for 3c SCF Energy: a.u. Frontier Orbitals HOMO ev LUMO ev S44

46 Singlet Optimized Coordinates for 3c Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S45

All solvents and reagents were used as obtained. 1H NMR spectra were recorded with a Varian

SUPPLEMETARY OTE Chemistry All solvents and reagents were used as obtained. 1H MR spectra were recorded with a Varian Inova 600 MR spectrometer and referenced to dimethylsulfoxide. Chemical shifts are