Hadil Shalan, Alexander Colbert, Thanh Truc Nguyen, Mallory Kato, and Lionel Cheruzel*

Transcription

1 Correlating the para-substituent effects on Ru(II)-polypyridine photophysical properties and on the corresponding hybrid P450 BM3 enzymes photocatalytic activity. Hadil Shalan, Alexander Colbert, Thanh Truc Nguyen, Mallory Kato, and Lionel Cheruzel* Department of Chemistry, San Jose State University, San Jose, CA United States Table of Contents: Detailed synthesis of the cis-ru(x 2 bpy) 2 Cl 2 precursors....p.2 Characterization of the Ru(X 2 bpy) 2 (PhenIA) compounds.....p.4 Figure S1. Theoretical and Experimental mass spectra for the complexes p.5 Figure S2. Mass spectra of the hybrid enzymes P1-P7 confirming the covalent attachment of the corresponding photosensitizer.....p.6 Table S1. Relevant Hammett and Brown-Okamoto values used in this study....p.6 Figure S3. Individual emission spectra for the model complexes 1-7 and the corresponding hybrid enzymes P1-P7.. p.7 Figure S4. Correlation of the absorption and emission energy with the energy gap....p.8 Figure S5. Correlation of A) E(III/II) oxidation potential; B) absorption and emission energies; C) 1 H NMR chemical shift and D) quantum yield for complexes 1-7 vs. Σσ p value...p.8 Figure S6. Partial MO diagram illustrating the effect of the substituents on the frontier orbitals of the Ru(4,4 -X 2 bpy) 2 bpy)] 2+ complexes p.9 Figure S7. Trends in the first reduction potential for the complexes 1-7 vs. the Σσ p+ and Σσ p parameters p.9 Figure S8. A) Luminescence decay for the complexes 1-7 with the best fit shown as black traces; B) Stern-Volmer plots of the luminescence quenching by sodium diethyldithiocarbamate p.10 Figure S9. Linear free energy relationship of the logarithm of the quenching rate vs. Σσ p value...p.10 Figure S10. A) Initial reaction rates in the selective hydroxylation of the chromogenic nitrophenoxy substrate, benzoxy-4-nitrobenzene, by the hybrid enzymes P1-P7; B) Linear free energy relationship between the logarithm of the ratio of initial reaction rates vs. the mixed Σσ p+ and Σσ p parameters..p.11 Figure S11. Linear free energy relationship of the logarithm of the photocatalytic initial reaction rates vs. Σσ p (A) or Σσ p+ (B) values p.11

2 Detailed synthesis of the cis-ru(x 2 bpy) 2 Cl 2 precursors cis-ru(4,4 -dichloro-2,2 -bipyridine) 2 Cl 2 RuCl 3 3H 2 O (0.25 g, 1 mmol) was added to a solution of LiCl (1.7 g, 39 mmol) in ethylene glycol/water (25 ml, 4:1) at 110 C. After 15 min, Cl 2 bpy (0.60 g, 2.0 mmol) was added. After 12 min glucose (0.36 g, 2.0 mmol) was added and allowed to react for 10 min, at which point ascorbic acid (0.089 g, 0.5 mmol) was added. The reaction solution was maintained at 110 C for 30 min. The reaction was quenched with the addition of 10 ml of a saturated NaCl solution and cooled to 0 C for 60 min. The dark purple precipitate (0.46 g, 74%) was filtered and washed with the NaCl solution. cis-ru(2,2 -bipyridine) 2 Cl 2 The precursor compound was prepared as above to yield the desired product as a violet precipitate (0.48 g, 85%). cis-ru(4,4 -Dimethyl-2,2 -bipyridine) 2 Cl 2 The precursor compound was prepared as above to yield the desired product as a violet precipitate (0.46 g, 76%). cis-[ru(4,4 -Di-tert-butyl-2,2 -bipyridine) 2 Cl 2 RuCl 3 3H 2 O (0.25 g, 1 mmol) was added to a solution of LiCl (1.7 g, 39 mmol) in ethylene glycol/water (24 ml, 5:1) at 110 C. After 15 min, (tbu)2bpy (0.43 g, 2.0 mmol) was added. A reaction time of 25 minutes was necessary to dissolve the highly lipophilic ligand, after which glucose (0.36 g, 2.0 mmol, 2 eq) was added and allowed to react for 10 min. Additional reducing agent was necessary; therefore increased ascorbic acid was used (0.12 g, 0.7 mmol, 0.7 eq). Upon the addition of the ascorbic acid, the reaction solution was maintained at 110 C for 30 min. The reaction was quenched with the addition of 10 ml of a saturated NaCl solution and cooled to 0 C for 60 min. The dark purple precipitate was filtered, washed with the NaCl solution. Viscous violet solution yielded a dark violet precipitate after vacuum filtration. Resultant powder was dissolved in ethyl acetate, and the insoluble powder was filtered off. The product was recrystallized with the dropwise addition of hexane to yield a fine black powder (0.52 g, 67%). cis-ru(4,4 -Diphenoxy-2,2 -bipyridine) 2 Cl 2 RuCl 3 3H 2 O (0.25 g, 1 mmol) was added to a solution of LiCl (1.7 g, 39 mmol) in ethylene glycol/water (25 ml, 4:1) at 110 C. After 15 min, (OPh) 2 bpy (0.43 g, 2.0 mmol) was added. After 20 min, glucose (0.36 g, 2.0 mmol) was added and allowed to react for 10 min, at which point ascorbic acid (0.089 g, 0.5 mmol) was added. The reaction solution was maintained at 110 C for 30 min. The reaction was quenched with the addition of 10 ml of a saturated NaCl solution and cooled to 0 C for 60 min. The smooth, shiny violet microcrystalline precipitate (0.92 g, 53%) was filtered and washed with the NaCl solution. 2

3 cis-ru(4,4 -Dimethoxy-2,2 -bipyridine) 2 Cl 2 RuCl 3 3H 2 O (0.25 g, 1 mmol) was added to a solution of LiCl (1.7 g, 39 mmol) in ethylene glycol/water (25 ml, 4:1) at 110 C. After 15 min, (MeO) 2 bpy (0.43 g, 2.0 mmol) was added. After 12 min glucose (0.36 g, 2.0 mmol, 2 eq) was added and allowed to react for 10 min, at which point ascorbic acid (0.089 g, 0.5 mmol) was added. The reaction solution was maintained at 110 C for 30 min. The reaction was quenched with the addition of 10 ml of a saturated NaCl solution and cooled to 0 C for 60 min. The smooth, shiny violet microcrystalline precipitate (0.37g, 76%) was filtered and washed with the NaCl solution. cis-ru(4,4 -Dimethylamino-2,2 -bipyridine) 2 Cl 2 RuCl 3 3H 2 O (0.25 g, 1 mmol) was added to a solution of LiCl (1.7 g, 39 mmol) in ethylene glycol/water (25 ml, 4:1) at 110 C. After 15 min, (Me 2 N) 2 bpy (0.54 g, 2.0 mmol) was added. After 12 min glucose (0.36 g, 2.0 mmol, 2 eq) was added and allowed to react for 10 min, at which point ascorbic acid (0.28 g, 1.6 mmol) was added. The reaction solution was maintained at 110 C for 30 min. The reaction was quenched with the addition of 10 ml of a saturated NaCl solution and cooled to 0 C for 60 min. The blue/purple precipitate (0.34 g, 47%) was filtered, washed with the NaCl solution. 3

4 Characterization of the Ru(X 2 bpy) 2 (PhenIA) compounds [Ru(4,4 -dichloro-2,2 -bipyridine) 2 (5-iodoacetamido-1,10-phenanthroline)] 2PF 6. Isolated as an orange powder (0.044 g, 85%). 1 H NMR (400 MHz, d 6 -DMSO): (s, 1H, PhenIA), 9.15 (s, 4H, Cl 2 bpy), (dd, 2H, PhenIA), 8.61 (s, 1H, PhenIA), (d, 2H, PhenIA), 7.87 (d, 4H, Cl 2 bpy), 7.69 (d, 2H, PhenIA), 7.44 (d, 4H, Cl 2 bpy), 4.08 (s, 2H, PhenIA). [Ru(2,2 -bipyridine) 2 (5-iodoacetamido-1,10-phenanthroline)] 2PF 6. Isolated as a red-orange powder (0.051 g, 90%). 1 H NMR (400 MHz, d 6 -DMSO): δ (ppm) (s, 1H, PhenIA), 8.82 (m, 6H, bpy, PhenIA), 8.63 (s, 1H, PhenIA), (m, 6H, bpy, PhenIA), 7.92 (d, 1H, PhenIA), 7.82 (m, 3H, bpy, PhenIA), 7.57 (d, 4H, bpy), 7.35 (d, 2H, bpy), 4.09 (s, 2H, PhenIA). [Ru(4,4 -di-tbutyl-2,2 -bipyridine) 2 (5-iodoacetamido-1,10-phenanthroline)] 2PF 6. Isolated as a light orange powder (0.037g, 82%). 1 H NMR (400 MHz, d 6 -DMSO): (s, 1H, PhenIA), 8.84 (s, 4H, tbu 2 bpy), 8.74 (d, 2H, PhenIA), 8.59 (s, 1H, PhenIA), 8.08 (d, 1H, PhenIA), 7.99 (d, 2H, PhenIA), 7.85 (d, 1H, PhenIA), 7.62 (d, 4H, tbu 2 bpy), 7.41 (d, 2H, tbu 2 bpy), 7.31 (d, 2H, tbu 2 bpy), 4.09 (s, 2H, PhenIA), 1.24 (s, 36H, tbu 2 bpy). [Ru(4,4 -dimethyl-2,2 -bipyridine) 2 (5-iodoacetamido-1,10-phenanthroline)] 2PF 6. Isolated as an orange powder (0.46 g, 72%). 1 H NMR (400 MHz, d 6 -DMSO): δ (ppm) (s, 1H, PhenIA), 8.84 (d, 1H, PhenIA), 8.74 (m, 5H, Me 2 bpy, PhenIA), 8.59 (s, 1H, PhenIA), 8.19 (d, 1H, PhenIA), 8.03 (d, 1H, PhenIA), 7.99 (dd, 1H, PhenIA), 7.65 (d, 2H, Me 2 bpy), 7.35 (d, 4H, Me 2 bpy), 7.35 (d, 1H, PhenIA), 7.17 (d, 2H, Me 2 bpy), 3.37 (s, 12H, Me 2 bpy), 4.09 (s, 2H, PhenIA). [Ru(4,4 -diphenoxy-2,2 -bipyridine) 2 (5-iodoacetamido-1,10-phenanthroline)] 2PF 6. Isolated as an orange powder (0.032g, 78%). 1 H NMR (400 MHz, d 6 -DMSO): δ (ppm) (s, 1H, PhenIA), 8.74 (d, 1H, PhenIA), 8.69 (m, 5H, OPhe 2 bpy, PHenIA), 8.32 (s, 1H, PhenIA), 8.19 (d, 1H, PhenIA), 7.90 (d, 1H, PhenIA), 7.83 (d, 1H, PhenIA), (m, 25H, OPhe 2 bpy, PhenIA), 6.87 (dd, 4H, OPhe 2 bpy), 4.07 (s, 2H, PhenIA) [Ru(4,4 -dimethoxy-2,2 -bipyridine) 2 (5-iodoacetamido-1,10-phenanthroline)] 2PF 6. Isolated as a dark red powder (0.047g, 85%). 1 H NMR (400 MHz, d 6 -DMSO): δ (ppm) (s, 1H, PhenIA), 8.74 (d, 2H, PhenIA), 8.58 (s, 1H, PhenIA), 8.46 (s, 4H, OMe 2 bpy), 8.32 (d, 1H, PhenIA), 8.12 (d, 1H, PhenIA), (d, 2H, PhenIA), 7.60 (d, 2H, OMe 2 bpy), 7.21 (d, 4H, OMe 2 bpy), 6.92 (d, 2H, OMe 2 bpy), 3.97 (s, 6H, OMe 2 bpy), 4.07 (s, 2H, PhenIA). [Ru(4,4 -bis(dimethylamino)-2,2 -bipyridine) 2 (5-iodoacetamido-1,10- phenanthroline)] 2PF 6. Isolated as a brown powder (0.022g, 64%). 1 H NMR (400 MHz, d 6 -DMSO): δ (ppm) (s, 1H, PhenIA), 8.60 (d, 1H, PhenIA), 8.49 (s, 1H, PhenIA), 8.30 (d, 1H, PhenIA), 8.18 (d, 1H, PhenIA), 7.99 (d, 2H, PhenIA), 7.72 (d, 4H, Me 2 bpy), 7.24 (d, 2H, (NMe 2 ) 2 bpy), 6.99 (d, 1H, PhenIA), 6.82 (d, 4H, (NMe 2 ) 2 bpy), 6.46 (d, 2H, (NMe 2 ) 2 bpy), 2.48 (s, 12H, (N(Me) 2 ) 2 bpy), 4.12 (s, 2H, PhenIA). 4

5 Figure S1. Theoretical and experimental mass spectra for the complexes 1-7 5

6 Proteins Theoretical mass P P P P P P P Figure S2. Mass Spectra of the hybrid enzymes P1-P7 confirming the covalent attachment of the corresponding photosensitizer. The determined mass values are consistent with the ones predicted for a 1:1 covalent attachment of the photosensitizer to the sl407c heme domain shown in the table. Table S1. Relevant Hammett and Brown-Okamoto values used in this study. Substituent σ m σ p σ p+ Cl H Me tbu OMe OPhe NMe

7 Figure S3: Individual emission spectra for the model complexes 1-7 and the corresponding hybrid enzymes P1-P7. 7

8 Figure S4. Correlation of the absorption and emission energy with the energy gap, ΔE, expressed as the difference in the oxidation (E(III/II)) and first reduction (E(II/I)) potentials. Figure S5. Correlations of A) E(III/II) oxidation potential; B) absorption and emission energies; C) 1 H NMR chemical shift and D) quantum yield for the complexes 1-7 vs. the Σσ p value. 8

9 Figure S6. Partial MO diagram illustrating the effect of the substituents on the frontier orbitals of the Ru(4,4 -X 2 bpy) 2 bpy)] 2+ complexes as the electronic donating ability of the substituent is increased across the series. Figure S7. Trends in the first reduction potential for the complexes 1-7 vs. the Σσ p+ (A) and Σσ p (B) parameters. 9

10 Figure S8. A) Luminescence decay for the complexes 1-7 with the best fit shown as black traces; B) Stern-Volmer plots of the luminescence quenching by sodium diethyldithiocarbamate. Figure S9. Linear free energy relationship of the logarithm of the ratio of quenching rates vs Σσ p value. 10

11 Figure S10. A) Initial reaction rates in the selective hydroxylation of the chromogenic nitro-phenoxy substrate, benzoxy-4-nitrobenzene, by the hybrid enzymes P1-P7; B) Linear free energy relationship between the logarithm of the ratio of initial reaction rates vs. the mixed Σσ p+ and Σσ p parameters. Figure S11. Linear free energy relationship of the logarithm of the photocatalytic initial reaction rates for the hydroxylation of 16-nitrophenoxyhexadecanoic acid vs. Σσ p+ (A) or Σσ p (B) parameters. 11