Experimental Supporting Information Organic Dye

Experimental Supporting Information Organic Dye Catalyzed, Visible-Light Photoredox Bromination of Arenes and Heteroarenes using NBromosuccinimide David A. Rogers, Roxanne G. Brown, Zachary C. Brandeburg, Eric Y. Ko, Megan D. Hopkins, Gabriel LeBlanc and Angus A. Lamar* Department of Chemistry and Biochemistry, The University of Tulsa, 800 S. Tucker Dr., Tulsa, OK 74104, USA. [email protected]

Index General information - LED chamber

S-1

Electrochemistry Information

S-2

Characterization of Compounds 3 and 5

S-3

1

S-5

H and 13C NMR Spectra

Figure S1. On the left – A red LED strip (620 nm) light bath reaction vessel On the right – A white LED strip (cool white) light bath reaction vessel Photocatalytic reactions were performed in a light bath which was constructed in our laboratory similar to our previous reports as follows.1-3 Waterproof 5050 LED strips (12V with power adapter, 18 LEDs/foot, approximately 0.24 Watt per LED – 72 Watt per strip) are coiled around the interior of evaporating dish (170mm x 90mm) using the adhesive backing of the LED strip. A Petri dish (150 x 20 mm) is placed upside down at the bottom of the dish to serve as an elevated glass “floor” to ensure that a round-bottom flask receives maximum light exposure. The temperature inside the dish is monitored and is generally maintained (air-cooled) between 19-22 oC (the temperature has not been observed above 25 o C).

S-1

Methods for electrochemical experiments Electrochemical experiments were performed using a BioLogic SP-200 Potentiostat using a platinum disk working electrode, a platinum mesh counter electrode, and a silver wire as the quasi-reference electrode. The electrolyte consisted of 0.25 mM erythrosine B and 100 mM tetrabutylammonium hexafluorophosphate in acetonitrile. In some experiments, 1 mM ferrocene was used as an internal standard, as well as for calibration of the quasi-reference electrode. The ferrocene formal potential was found to be 0.477 V vs the silver wire quasi-reference electrode. Cyclic voltammetry was performed using a scan rate of 500 mV/s.

Figure S2. Cyclic voltammograms of (A) ferrocene, (B) NBS with ferrocene, (C) Ery B with (black) and without (red) ferrocene, and (D) Ery B with ferrocene using a platinum disk working electrode. Major redox peaks have been labeled as oxidation (O) or reduction (R) along with an abbreviation for the chemical entity. Formal potentials for irreversible electrochemical behavior were estimated using the half-wave potential. Note that the oxidation peak observed in (D), labeled EryBO2, only appears after a reducing potential (below -1V vs Fc/Fc+) has been reached and is therefore not an oxidation of the ground state Ery B.

S-2

1-Bromonaphthalene (3) The title compound was quantified using gas chromatography with adamantane as an internal standard. A standard curve of 1-bromonaphthalene (Figure S3) was prepared in 5 separate reaction vessels by adding varying amounts of 1bromonaphthalene (between 0 and 0.25 mmol) to 3 mL of acetonitrile. To each of the 3 mL acetonitrile solutions was added 8 mL of hexanes and 0.156 mmol (20 mg) of adamantane. The acetonitrile solution was extracted with the hexanes, and 1 mL of the hexanes portion was removed for gas chromatography injection. Gas chromatography was performed using a Shimadzu GC-2010 Plus with GCMS-QP2010 with a Restek Rtx-5MS capillary column (30m; 0.25 mmID; 0.25 um df; Crossbond – 5% diphenyl/95% dimethyl pilosiloxane). The GC method was as follows: 40 °C for 5 minutes, then increase at 10 °C/minute for 16 minutes (up to 200 °C). 200 °C is maintained for 10 additional minutes. As seen in Figure S4, 1Bromonaphthalene is observed at 16.8 minutes, and confirmed by MS (EI) m/z 206 and 208 (M+ 1:1 ratio; 50% rel. intensity) 127 (100% rel. intensity) 63 (90% rel. intensity).

Theoretical % Yield 1-Bromonaphthalene

1-Bromonaphthalene/Adamantane after Extraction 120 110 100 90 80 70 60 50 40 30 20 10 0

y = 80.155x R² = 0.9948

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

1.4

1.5

Integration Ratio 1-Br-Naphth/Adamantane

Figure S3. Standard curve of 1-bromonaphthalene versus internal standard (adamantane)

Figure S4. Expanded view of a typical GCMS chromatogram.

S-3

1-Bromo-4-methoxybenzene (5) The title compound was observed by 1H NMR and compared to a reported spectrum.4 One equivalent of nitrobenzene was added as internal standard at the conclusion of the reaction time period. The 1H NMR spectrum is included within this supporting information document (Figure S10).

References: 1. Brueckner, A. C.; Hancock, E. N.; Anders, E. J.; Tierney, M. M.; Morgan, H. R.; Scott, K. A.; Lamar, A. A., Visible-light-mediated, nitrogen-centered radical amination of tertiary alkyl halides under metal-free conditions to form []-tertiary amines. Organic & biomolecular chemistry 2016, 14 (19), 4387-4392.

2. Hopkins, M. D.; Scott, K. A.; DeMier, B. C.; Morgan, H. R.; Macgruder, J. A.; Lamar, A. A., Formation of N-sulfonyl imines from iminoiodinanes by iodine-promoted, N-centered radical sulfonamidation of aldehydes. Organic & biomolecular chemistry 2017, 15 (43), 9209-9216.

3. Hopkins, M.; Brandeburg, Z.; Hanson, A.; Lamar, A., Visible-Light, Iodine-Promoted Formation of N-Sulfonyl Imines and NAlkylsulfonamides from Aldehydes and Hypervalent Iodine Reagents. Molecules 2018, 23 (8), 1838.

4. Braddock, D. C.; Cansell, G.; Hermitage, S. A., (Diacetoxyiodo)benzene-Lithium Bromide as a Convenient Electrophilic Br+ Source. Synlett 2004, 461-464.

S-4

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ 0.21 ZB-11-1H 0.20

Figure S5 - Product 4

0.19 0.18 0.17 0.16 0.15 0.14 0.13

Normalized Intensity

0.12 0.11 0.10 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 0.97 1.01 1.04 1.06 1.00 0.98 11

10

9

8

7

3.01 6 5 Chemical Shift (ppm)

4

3

2

1

0

S-5

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ AL-2-127-B-10min

Figure S6 - 2-methylnaphthalene (uncatalyzed reaction - 10 min) 0.025


0.020

0.015

0.010

0.005

0 1.01 1.99 0.94 2.13 1.00 9.5

9.0

8.5

8.0

7.5

7.0

6.5 6.0 Chemical Shift (ppm)

5.5

5.0

4.5

4.0

3.5

S-6

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ AL-2-127-B-2hr 0.013

0.012

Figure S7 - 2-methylnaphthalene (uncatalyzed reaction - 120 min)

0.011

0.010

0.009


0.008

0.007

0.006

0.005

0.004

0.003

0.002

0.001

0 0.38 1.01 3.79 1.44 0.66 1.72 2.47 1.31 9.5

9.0

8.5

8.0

7.5

0.75 0.89 7.0


5.5

5.0

4.5

4.0

3.5

S-7

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ AL-2-127-A-10min 0.019 0.018

Figure S8 - 2-methylnaphthalene (catalyzed reaction - 10 min)

0.017 0.016 0.015 0.014 0.013


0.012 0.011 0.010 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001 0 0.94 9.5

9.0

8.5

0.97 1.07 1.01 1.00 1.11 8.0

7.5

7.0


5.5

5.0

4.5

4.0

3.5

S-8

127.25

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ ZB-11-13C 0.30 128.67


77.00 76.68

125.61 124.00

0.15

0.10 135.97 132.97


77.32

0.20

24.15

0.25

0.05

0

220

200

180

160

140

120 100 Chemical Shift (ppm)

80

60

40

20

0

-20

S-9

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ 0.100

RB-Anisole-nitrobenzene25min

0.095 0.090

Figure S10 - anisole reaction (with nitrobenzene internal standard) 0.085 0.080 0.075 0.070 0.065


0.060 0.055 0.050 0.045 0.040 0.035 0.030 0.025 0.020 0.015 0.010 0.005 0 1.94 1.00 1.98 1.94 1.99 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

7.0

2.98 6.5 6.0 5.5 5.0 Chemical Shift (ppm)

4.5

4.0

4.36 3.19 3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

-0.5

S-10

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ 0.21 RB-89-pure 0.20 0.19


0.18 0.17 0.16 0.15 0.14 0.13


0.12 0.11 0.10 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 0.961.02 11

10

9

8

1.09 7


4

3.21 3

2

1

0

S-11

77.30 76.99 76.67

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ RB89-4000scans-13C

0.25


133.84

0.15

159.56

56.47

26.30

0.05

111.83 111.04

131.21 129.46

0.10

195.62


0.20

0

220

200

180

160

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80

60

40

20

0

-20

S-12


EK-64pureaftervacuum-5hrs

0.25



0.20

0.15

0.10

0.05

0 1.00 0.23 1.17 0.26 2.69 1.48 1.23 1.55 11

10

9

8

7


4

3

2

1

0

S-13


EK-64pureaftervacuum-5hrs

Figure S14 - Product 7 aromatic region 0.25


0.20

0.15

0.10

0.05

0 1.00 8.2

8.1

8.0

0.23 7.9

1.17 7.8

0.26

2.69


7.5

1.48

1.23 7.4

1.55 7.3

7.2

7.1

7.0

S-14

76.30 75.98 75.66

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ EK-64-13C-10000scans 0.30


0.25

0.05

112.15 110.84

122.49 119.80

125.22

126.89

128.85

0.10

0.00

0.15

129.70

155.57 153.87


0.20

0

220

200

180

160

140


80

60

40

20

0

-20

S-15


DR-6-41-f23-29-1H

Figure S16 - Product 8 0.25


0.20

0.15

0.10

0.05

0 2.00 1.04 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

7.0

2.00

6.5 6.0 5.5 5.0 Chemical Shift (ppm)

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

-0.5

S-16

101.57

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-6-41-F23-29-13C 0.30


146.96

124.28

113.00

0.15

0.10

109.55

148.55


112.26

0.20

77.31 76.99 76.67

0.25

0.05

0

-0.05

220

200

180

160

140


80

60

40

20

0

-20

S-17


ZB-1-NBS-7-pure-1H



0.20

0.15

0.10

0.05

0 0.92 2.04 1.03 1.00 1.18 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

7.0


4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

-0.5

S-18

117.12


ZB-1-NBS-5-pure-13C 0.30

127.82


77.31 77.00 76.68

124.12

0.25

132.26 129.65

0.10

106.12

0.15 150.54


129.31

0.20

0.05

0

220

200

180

160

140


80

60

40

20

0

-20

S-19

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-5-152-F40-54-1H 0.14

0.13


0.11

0.10


0.09

0.08

0.07

0.06

0.05

0.04

0.03

0.02

0.01

0 1.01 1.050.98 11

10

9

8

7


9.03 4

3

2

1

0

S-20

128.74

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-5-152-13C 0.30


115.48

31.36

76.67

126.21

0.20

0.10

109.83

145.07

0.15

0.05

34.20

149.83


77.30 76.98

0.25

0

220

200

180

160

140


80

60

40

20

0

-20

S-21


DR-5-189-1H-pure



0.20

0.15

0.10

0.05

0 0.99 1.04 0.99 11

10

9

8

7


1.11 4

3

6.72 2

1

0

S-22

24.04

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-5-189-13C-pure-FEB16 0.30


0.25

76.99 76.67

115.78

33.15

127.22

77.30

0.15

150.10 0.05

109.93

0.10

142.66


129.59

0.20

0

220

200

180

160

140


80

60

40

20

0

-20

S-23


DR-6-122-F15-18-1H



0.20

0.15

0.10

0.05

0 1.01 1.07 1.01 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

7.0


1.13 4.5

4.0

3.5

3.0

2.5

4.93 2.0

5.06 1.5

1.0

0.5

0

-0.5

S-24

26.83

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-6-122-13C 0.30 34.59


0.25

26.07 43.49

115.82

130.03 127.59

0.15

77.41 77.09 76.77

109.99

0.05

141.97

0.10

150.15


0.20

0 220

200

180

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140


80

60

40

20

0

-20

S-25


DR-5-140

Figure S26 Product 13 0.25


0.20

0.15

0.10

0.05

0 1.99 11

10

9

8

1.00 7


4

3

2

1

0

S-26

131.54

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-5-140-13C-5000scans 0.30


77.31 76.68

0.25

0.15

126.17

0.05

109.90

0.10

148.48


0.20

0

-0.05

220

200

180

160

140


80

60

40

20

0

-20

S-27


DR-6-69



0.20

0.15

0.10

0.05

0 1.00 1.01 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

1.00 7.0


4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

S-28

131.38



133.55

0.25

77.34 77.02 76.70

0.15

121.47

0.05

110.78

112.22

0.10

148.13


0.20

0

220

200

180

160

140


80

60

40

20

0

-20

S-29


DR-5-160-F26-41-1H



0.20

0.15

0.10

0.05

0

0.89 11.5

11.0

10.5

10.0

9.5

9.0

8.5

1.00 8.0

7.5

1.05 7.0

2.04


4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

-0.5

S-30

128.27



138.44

120.30

0.25

107.80

77.33 77.01 76.70

0.15

0.10

143.54


0.20

0.05

0 220

200

180

160

140


80

60

40

20

0

-20

S-31


DR-6-65-1h



0.20

0.15

0.10

0.05

0 2.00 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

2.06 7.0


4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

-0.5

S-32

131.19

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-6-65-5000scans-13C 0.30


108.37

0.25

76.69

77.33 77.01 0.15

122.56

0.10

140.91


0.20

0.05

0

220

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140


80

60

40

20

0

-20

S-33


DR-6-58-F15-27-1H



0.20

0.15

0.10

0.05

0 4.02 0.83 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

7.0


4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

S-34

76.68

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-6-58-13C-6000scans 77.31

0.30


0.25

131.92 121.34

0.15

24.59

0.10

116.84

136.89

0.05 168.28


0.20

0 220

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80

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40

20

0

-20

S-35


DR-6-29-1H-F7-18


0.25


0.20

0.15

0.10

0.05

0 1.02 11.5

11.0

10.5

10.0

9.5

9.0

2.02 8.5

8.0

7.5

7.0


4.5

4.0

3.5

3.0

4.01 2.5

5.90 2.0

5.95 1.5

1.0

0.5

0

-0.5

S-36

12.64

48.93

128.17

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-6-29-F7-16-13C-pure

18.56


0.17

57.49

0.16 0.15 0.14 0.13

135.04

0.11 0.10 0.09 0.08 0.07 0.06

133.96

0.04 0.03

77.48 77.16 76.84

0.05

170.23


0.12

0.02 0.01 0 220

200

180

160

140


80

60

40

20

0

-20

S-37


DR-5-178-F6-18-1H



0.20

0.15

0.10

0.05

0 1.00 0.95 2.11 2.19 1.02 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

7.0


4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

S-38

-0.5

118.99



0.25

129.52

0.15

77.35 77.03 76.71 95.61

0.05

126.99

141.49

127.02

0.10

139.60


0.20

0

220

200

180

160

140


80

60

40

20

0

-20

S-39


DR-5-128



0.20

0.15

0.10

0.05

0 1.00 12

1.97 1.00 1.03 11

10

9

8


5

4

3

2

1

0

S-40

121.83


120.11


110.53

0.25

77.00 76.68 77.32

128.14

0.15

141.21

0.10

122.96


0.20

0.05

0 220

200

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160

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80

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40

20

0

-20

S-41


DR-6-60-F52-57-1H



0.20

0.15

0.10

0.05

0 2.21 2.17 1.14 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

7.0


4.5

0.33 3.00 4.0

3.5

3.0

2.92 2.5

2.0

1.5

1.0

0.5

0

S-42

-0.5

129.20 127.00 124.13

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/

0.100

36.43

DR-6-60-13C


0.095 0.090 0.085 0.080 0.075 12.46

0.070

154.02

0.060 0.055 0.050

129.37

0.045 0.040

134.78

77.47 77.15 76.83

0.035 0.030

36.83

0.020 0.015

19.18

90.45

0.025 162.12


0.065

0.010 0.005 0 -0.005 220

200

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0

-20

S-43


DR-6-56-NaOHwash

0.24 0.23


0.22 0.21 0.20 0.19 0.18 0.17 0.16


0.15 0.14 0.13 0.12 0.11 0.10 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 3.00 3.00 3.02 11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

7.0


4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

-0.5

S-44

29.79


33.92


76.71 128.09

0.15

147.95

0.10

0.05

109.29

154.36 151.19


0.20

27.97

77.35 77.03

0.25

0 220

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0

-20

S-45


DR-6-137-1H



0.20

0.15

0.10

0.05

0 0.93 11.5

11.0

10.5

10.0

9.5

9.0

0.97 2.00 1.02 8.5

8.0

7.5

7.0


4.5

3.33 4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

-0.5

S-46

77.31 76.99

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-6-132-3900scans-sep6-13C

76.68

0.30


121.45 121.31

0.25

111.95

14.33

0.15

98.29

135.27

0.05

124.07

127.97 126.56

61.45

0.10

160.95


0.20

0

220

200

180

160

140


80

60

40

20

0

-20

S-47


DR-6-139-JUL24-2



0.20

0.15

0.10

0.05

0 2.04 11

10

9

8

2.16 1.01 0.96 7


3.22 4

3

2

1

0

S-48

77.30 76.67

This report was created by ACD/NMR Processor Academic Edition. For more information go to www.acdlabs.com/nmrproc/ DR-6-139A-F38-53-13C 0.30


0.25

124.85

0.10

134.66

0.05

21.74

58.07

128.82

129.62

0.15

148.84 145.80


0.20

0

220

200

180

160

140


80

60

40

20

0

-20

S-49