S1

Supporting Information

Systematic Ligand Variation to Modulate the Electrochemical

Properties of Iron and Manganese Complexes

Stefan S. Rohner,a) Niklas W. Kinzel,a), b) Christophe Werlé,b), * and Walter Leitnera), b), *

a) Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Worringerweg 2, 52074 Aachen,

Germany.

b) Max-Planck-Institute for Chemical Energy Conversion, Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany.

Corresponding Authors:

* E-mail for C. W.: christophe.werle@cec.mpg.de

* E-mail for W. L.: walter.leitner@cec.mpg.de

Table of Contents1. Synthetic Procedures and Characterizations ........................................................................................2

1.1. Synthesis of (H-dpaq) (5a) ............................................................................................................2

1.1. Synthesis of (H-dpaq5-OMe) (5b) .....................................................................................................3

1.2. Synthesis of (H-dpaq6-OMe) (5c) .....................................................................................................5

1.3. Synthesis of (H-dpaqPyr) (5d) .........................................................................................................7

1.4. Synthesis of (H-dpaqCF3)................................................................................................................9

2. Supporting Figures..............................................................................................................................13

2.1. NMR spectra ...............................................................................................................................13

2.2. Electrochemistry.........................................................................................................................21

Electronic Supplementary Material (ESI) for Dalton Transactions.This journal is © The Royal Society of Chemistry 2019

S2

1. Synthetic Procedures and Characterizations

5-chloro-8-nitroquinoline (6), 5-methoxy-8-nitroquinoline (7) and the H-dpaqNO2 ligand (5e) were

synthesized according to reported procedures.[1]

1.1. Synthesis of (H-dpaq) (5a)

NNH2

NHN

BrO

NHN

NO

N

N

a) b)

3a 4a 5a

Scheme S1. Reaction conditions: a) bromoacetylbromide, Na2CO3, MeCN, 0 °C, 20 min; b) bis(2-pyridylmethyl)amine, Na2CO3, MeCN, 0 °C to r.t, overnight.

2-Bromo-N-(quinolin-8-yl)acetamide (4a). Bromoacetylbromide (146 µL,

1.68 mmol) was slowly added at 0 °C to a mixture of 8-aminoquinoline (3a, 200 mg,

1.39 mmol) and sodium carbonate (206 mg, 1.94 mmol) in dry acetonitrile (10 mL).

The reaction mixture was stirred at 0 °C for 20 min before the fine dispersed solid

was recovered by filtration. The filter cake was washed with acetonitrile (10 mL) and diethylether (10 mL)

before drying under high vacuum led to 2-Bromo-N-(quinolin-8-yl)acetamide (4a) as a light beige solid

(318 mg, 1.20 mmol, 86%). The obtained analytical data are consistent with those previously reported in

the literature.[1d] 1H-NMR (400 MHz, CD3OD, 296 K): 8.88 (dd, J = 4.2 Hz, 1.7 Hz, 1H), 8.62 (dd,

J = 7.7 Hz, 1.3 Hz, 1H), 8.31 (dd, J = 8.3 Hz, 1.7 Hz, 1H), 7.66 (dd, J = 8.3 Hz, 1.3 Hz, 1H), 7.57 (dd,

J = 8.2 Hz, 4.1 Hz, 2H), 4.28 (s, 2H). 13C{1H}-NMR (101 MHz, CD3OD, 296 K): 167.0, 150.2, 140.0, 137.7,

135.1, 129.6, 127.9, 124.1, 123.2, 118.1, 30.2.

2-(Bis(pyridin-2-ylmethyl)amino)-N-(quinolin-8-yl) acetamide (H-dpaq, 5a).

Bis(2-pyridylmethyl)amine (162 µL, 0.90 mmol) was slowly added at 0 °C to a

mixture of 2-bromo-N-(quinolin-8-yl)acetamide (4a, 270 mg, 1.02 mmol) and

sodium carbonate (111 mg, 1.05 mmol) in acetonitrile (15 mL). The mixture was

slowly warmed up to room temperature and stirring was continued overnight.

The resulting mixture was filtered over fritted glass to remove excess sodium carbonate. The solution was

concentrated to 3 mL leading to the precipitation of a beige solid that was recovered by filtration. The

NHN

BrO

NHN

NO

N

N

S3

residue was washed with diethylether (10 mL). Subsequent drying under high vacuum led to H-dpaq (5a)

as a beige solid (356 mg, 0.929 mmol, 67%). The obtained analytical data are consistent with those

previously reported in the literature.[1d] 1H-NMR (400 MHz, CD3CN, 296 K): 11.46 (s, 1H), 9.01 (dd,

J = 1.7 Hz, 2.6 Hz, 1H), 8.65 (dd, J = 1.1 Hz, 6.5 Hz, 1H), 8.47 (d, J = 4.9 Hz, 2H), 8.31 (dd, J = 1.6 Hz, 6.8 Hz,

1H), 7.90 (d, J = 7.9 Hz, 2H), 7.70 (td, J = 1.7 Hz, 6.0 Hz, 2H), 7.63-7.58 (m, 2H), 7.53 (t, J = 8.0 Hz, 1H), 7.18

(dd, J = 2.1 Hz, 7.6 Hz, 2H), 3.95 (s, 4H), 3.50 (s, 2H).13C{1H}-NMR (101 MHz, CD3CN, 296 K): 170.4,

159.3, 149.9, 149.8, 139.4, 137.5, 137.3, 135.4, 129.1, 128.0, 124.4, 123.3, 123.0, 122.6, 116.6, 61.7, 60.1.

1.1. Synthesis of (H-dpaq5-OMe) (5b)

Cl

NO2

H2N NNO2

Cl

NNO2

OMe

NNH2

OMe

NHN

OMe

OBr

NHN

OMe

NO

N

N

a) b) c)

d) e)

6 7a 3b

4b 5b

3b

Scheme S2. Reaction conditions: a) glycerol, NaI, H2SO4, 150 °C, 2 h ; b) NaOMe, MeOH, reflux, 2 h; c) SnCl2 2 H2O, EtOH, ∙reflux, 1 h; d) bromoacetylbromide, Na2CO3, MeCN, 0 °C, 20 min; e) bis(2-pyridylmethyl)amine, Na2CO3, MeCN, 0 °C to r.t., overnight.

5-Methoxyquinolin-8-amine (3b). The synthesis was performed according to a modified

reported procedure.[2] A mixture of 5-methoxy-8-nitroquinoline (7, 796 mg, 3.90 mmol)

and tin chloride dihydrate (2.65 g, 11.8 mmol) in ethanol (25 mL) was stirred under reflux

for one hour. After cooling to room temperature, the solution was diluted with ethyl

acetate (15 mL) before an aqueous solution of sodium hydroxide (5 M) was added until pH 11 was

reached. The organic phase was separated, washed with brine (3 x 15 mL) and dried over anhydrous

sodium sulfate. The volatiles were removed in vacuo and drying of the obtained residue under high

vacuum led to 5-methoxyquinolin-8-amine (3b) as a black highly viscous gel (577 mg, 3.31 mmol, 85%).

The obtained analytical data are consistent with those previously reported in the literature.[2] 1H-NMR

(400 MHz, CDCl3, 296 K): 8.77 (dd, J = 1.8 Hz, 4.2 Hz, 1H), 8.47 (dd, J = 1.7 Hz, 8.4 Hz, 1H), 7.33 (dd,

NNH2

OMe

S4

J = 4.2 Hz, 8.5 Hz, 1H), 6.83 (d, J = 8.2 Hz, 1H), 6.68 (d, J = 8.2 Hz, 1H), 4.46 (br s, 2H), 3.88 (s, 3H). 13C-APT-NMR (101 MHz, CDCl3, 296 K): 148.1, 147.0, 139.1, 137.4, 130.8, 121.1, 120.4, 109.8, 105.4,

55.9.

2-Bromo-N-(5-methoxyquinolin-8-yl)acetamide (4b). Bromoacetylbromide

(290 µL, 3.35 mmol) was slowly added at 0 °C to a mixture of 5-methoxyquinolin-8-

amine (3b, 485 mg, 2.78 mmol) and sodium carbonate (415 mg, 3.88 mmol) in dry

acetonitrile (20 mL). The reaction mixture was stirred at 0 °C for 20 min before the

fine dispersed solid was recovered by filtration. The obtained solid was washed with

acetonitrile (2 mL). Subsequent drying under high vacuum led to 2-bromo-N-(5-methoxyquinolin-8-

yl)acetamide (4b) as a dark brown solid (630 mg, 3,62 mmol, 80%). 1H-NMR (300 MHz, CD3CN, 296 K):

9.98 (s, 1H), 8.94 (d, J = 8.9 Hz, 1H), 8.89 (dd, J = 1.6 Hz, 4.9 Hz, 1H), 8.31 (d, J = 8.7 Hz, 1H), 7.73 (dd, J

= 4.9 Hz, 8.6 Hz, 1H), 7.08 (dd, J = 3.7 Hz, 8.7 Hz, 1H), 4.25 (d, J = 2.9 Hz, 2H), 3.96 (s, 3H). 13C-APT-NMR

(101 MHz, CD3OD, 296 K): 152.4, 148.4, 143.2, 132.7, 124.7, 123.2, 122.9, 120.6, 109.8, 104.9, 56.9,

26.2.

2-(Bis(pyridin-2-ylmethyl)amino)-N-(5-methoxyquinolin-8-yl)acetamide (H-

dpaq5-OMe, 5b). Bis(2-pyridylmethyl)amine (256 µL, 1.42 mmol) was slowly added

at 0 °C to a mixture of 2-bromo-N-(5-methoxyquinolin-8-yl)acetamide (4b,

437 mg, 1.48 mmol) and sodium carbonate (169 mg, 1.59 mmol) in acetonitrile

(23 mL). The mixture was then slowly warmed up to room temperature where it

was stirred overnight and subsequently filtered over filter paper to remove

excess sodium carbonate. The solvent of the filtrate was removed in vacuo and drying under high vacuum

led to 2-(bis(pyridin-2-ylmethyl)amino)-N-(5-methoxyquinolin-8-yl)acetamide (5b) as a dark brown

liquid (102 mg, 0.247 mmol, 19%). The obtained analytical data are consistent with those previously

reported in the literature.[1c] 1H-NMR (400 MHz, CDCl3, 296 K): 11.36 (s, 1H), 8.93 (dd, J = 1.8 Hz,

4.2 Hz, 1H), 8.68 (d, J = 8.5 Hz, 1H), 8.61 (dd, J = 1.7 Hz, 8.4 Hz, 1H), 8.52 (ddd, J = 0.9 Hz, 1.8 Hz, 4.8 Hz,

2H), 7.97 (dt, J = 1.2 Hz, 7.9 Hz, 2H), 7.65 (tdd, J = 1.8 Hz, 4.3 Hz, 7.7 Hz, 2H), 7.49 (dd, J = 4.2 Hz, 8.4 Hz,

1H), 7.20-7.12 (m, 2H), 6.83 (d, J = 8.6 Hz, 1H), 4.01 (s, 4H), 3.99 (s, 3H), 3.51 (d, J = 1.2 Hz, 2H). 13C-APT-NMR (101 MHz, CDCl3, 296 K): 169.1, 158.5, 150.5, 149.3, 139.7, 136.7, 136.6, 131.4, 128.0,

123.5, 122.5, 122.1, 120.7, 116.9, 104.6, 61.2, 59.4, 55.9.

NHN

OMe

OBr

NHN

OMe

NO

N

N

S5

1.2. Synthesis of (H-dpaq6-OMe) (5c)

NNO2

NNH2

OMe OMe

NHN

BrO

OMeN

HNN

O

N

N

OMe

a) b) c)

7b 3c 4c 5c

Scheme S3. Reaction conditions: a) SnCl2 2 H2O, EtOH, reflux, 1 h; b) bromoacetylbromide, Na2CO3, MeCN, 0 °C, 20 min; c) ∙bis(2-pyridylmethyl)amine, Na2CO3, MeCN, 0 °C to r.t., overnight.

6-Methoxyquinolin-8-amine (3c). The synthesis was performed according to a

modified reported procedure.[2] A mixture of 6-methoxy-8-nitroquinoline (7b,

1.00 g, 4.91 mmol) and tin chloride dihydrate (3.33 g, 14.8 mmol) in ethanol (20 mL)

was stirred under reflux for one hour. After cooling to room temperature, the

solution was diluted with ethyl acetate (15 mL) before an aqueous solution of sodium hydroxide (5 M)

was added until pH 11 was reached. The organic phase was separated, washed with brine (3 x 15 mL) and

dried over anhydrous sodium sulfate. The volatiles were removed in vacuo and drying of the obtained

residue under high vacuum led to 6-methoxyquinolin-8-amine (3c) as a black highly viscous gel (656 mg,

3.77 mmol, 77%). The obtained analytical data are consistent with those previously reported in the

literature.[2] 1H-NMR (400 MHz, CDCl3, 296 K): 8.60 (dd, J = 1.6 Hz, 4.3 Hz, 1H), 7.96 (dd, J = 1.6 Hz,

8.3 Hz, 1H), 7.32 (dd, J = 4.3 Hz, 8.3 Hz, 1H), 6.58 (d, J = 2.5 Hz, 1H), 6.48 (d, J = 2.6 Hz, 1H), 5.01 (br s, 2H),

3.88 (s, 3H). 13C-APT-NMR (101 MHz, CDCl3, 296 K): 159.4, 145.4, 145.2, 135.5, 130.4, 122.2, 102.2,

95.0, 55.8.

2-Bromo-N-(6-methoxyquinolin-8-yl)acetamide (4c). Bromoacetylbromide (290 µL,

3.35 mmol) was slowly added at 0 °C to a mixture of 6-methoxyquinolin-8-amine (3c,

485 mg, 2.78 mmol) and sodium carbonate (415 mg, 3.88 mmol) in dry acetonitrile

(20 mL). The reaction mixture was stirred at 0 °C for 20 min before the fine dispersed

solid was recovered by filtration. The obtained solid was washed with acetonitrile (2 mL). Subsequent

drying under high vacuum led to 2-bromo-N-(6-methoxyquinolin-8-yl)acetamide (4c) as a light brown

solid (475 mg, 1.61 mmol, 58%). 1H-NMR (400 MHz, CD3OD, 296 K): 8.97 (dd, J = 8.4 Hz, 1.5 Hz, 1H),

8.93 (dd, J = 5.2 Hz, 1.5 Hz, 1H), 7.98 (dd, J = 8.5 Hz, 5.2 Hz, 1H), 7.80 (d, J = 2.6 Hz, 1H), 7.59 (d, J = 2.7 Hz,

NNH2

OMe

NHN

BrO

OMe

S6

1H), 4.24 (s, 2H), 4.03 (s, 3H). 13C-APT-NMR (101 MHz, CD3OD, 296 K): 169.1, 161.2, 145.6, 143.7, 140.0,

132.7, 132.0, 132.7, 122.8, 105.9, 57.0, 29.2.

2-(Bis(pyridin-2-ylmethyl)amino)-N-(6-methoxyquinolin-8-yl)acetamide (H-

dpaq6-OMe, 5c). Bis(2-pyridylmethyl)amine (234 µL, 1.30 mmol) was slowly

added at 0 °C to a mixture of 2-bromo-N-(6-methoxyquinolin-8-yl)acetamide

(4c, 387 mg, 1.31 mmol) and sodium carbonate (154 mg, 1.45 mmol) in

acetonitrile (25 mL). The mixture was then slowly warmed up to room

temperature where it was stirred overnight and subsequently filtered over fritted glass to remove excess

sodium carbonate. The solvent of the filtrate was removed in vacuo and drying under high vacuum led to

2-(bis(pyridin-2-ylmethyl)amino)-N-(6-methoxyquinolin-8-yl)acetamide (5c) as a dark red liquid

(102 mg, 0.247 mmol, 19%).1H-NMR (400 MHz, CDCl3, 296 K): 11.47 (s, 1H), 8.71 (dd, J = 1.6 Hz, 4.2 Hz,

1H), 8.43 (ddd, J = 0.9 Hz, 1.8 Hz, 4.9 Hz, 2H), 8.39 (d, J = 2.7 Hz, 1H), 7.99 (dd, J = 1.6 Hz, 8.3 Hz, 1H), 7.89

(dt, J = 1.1 Hz, 7.9 Hz, 2H), 7.63-7.54 (m, 2H), 7.39 (dd, J = 4.2 Hz, 8.3 Hz, 1H), 7.08 (ddd, J = 1.2 Hz, 4.9 Hz,

7.5 Hz, 2H), 6.73 (d, J = 2.7 Hz, 1H), 3.92 (s, 4H), 3.82 (s, 3H), 3.45 (s, 2H). 13C-APT-NMR (101 MHz, CDCl3,

296 K): 169.5, 158.3, 158.0, 148.9, 145.5, 136.6, 135.3, 135.1, 134.9, 129.0, 123.3, 122.3, 122.1, 108.8,

99.7, 60.9, 59.2, 55.5. HRMS (ESI+): m/z: calcd. for C24H23N5O2 [M+Na]+: 436.17440; found: 436.17435.

NHN

NO

N

N

OMe

S7

1.3. Synthesis of (H-dpaqPyr) (5d)

N NN

N NH N

NHN N

O

N

N

N

Br

N

O

O a) b) c)

d)

5d

8 9 10 11

11

Scheme S4. Reaction conditions: a) pyren-1-ylboronic acid, Pd(PPh3)4, K2CO3, MeCN, 0 °C, 20 min; b) trimethylorthoformate, r.t., 1 h; c) NaBH4, DCM/MeOH, r.t., overnight; d) 2-bromo-N-(quinolin-8-yl)acetamide (4a), Na2CO3, MeCN/DCM, 0 °C to r.t., overnight.

5-(Pyren-1-yl)picolinaldehyde (9). The synthesis was performed according to a modified

reported procedure.[3] A mixture of pyren-1-ylboronic acid (0.738 g, 3.00 mmol), 5-

bromopicolinaldehyde (8, 0.558 g, 3.00 mmol), tetrakis(triphenylphosphine)palladium

(0.347 g, 0.300 mmol) and potassium carbonate (1.24 g, 9.00 mmol) in tetrahydrofuran

(45 mL) and degassed water (9 mL) was stirred under reflux for 21 h. After that time, the

reaction mixture was poured into cold water (50 mL) and was extracted with

dichloromethane (3 x 25 mL). The combined organic phases were dried over anhydrous sodium sulfate

and the volatiles were removed in vacuo. The brownish-yellow residue was purified via column

chromatography over silica with a mixture of petrol ether/ethyl acetate (gradient PE/EtOAc 9:1 up to 0:1)

as eluent. 5-(Pyren-1-yl)picolinaldehyde (9) was obtained as a yellow solid (0.640 g, 2.08 mmol, 70%).

1H-NMR (600 MHz, CD2Cl2, 296 K): 10.21 (s, 1H), 9.06 (s, 1H), 8.28 (d, J = 7.8 Hz, 1H), 8.26 (d, J = 7.8 Hz,

1H), 8.22 (d, J = 7.5 Hz, 1H), 8.17-8.12 (m, 4H), 8.11-8.05 (m, 3H), 7.98 (d, J = 7.8 Hz, 1H). 13C{1H}-NMR-(151 MHz, CD2Cl2, 296 K): 193.6, 152.0, 151.9, 141.6, 139.1, 132.8, 132.0, 131.8, 131.2 ,

129.0, 128.9, 128.6, 127.9, 127.7, 126.8, 126.2, 125.8, 125.3, 125.0, 124.3, 121.6. HRMS (ESI+): m/z: calcd.

for C22H13NO [M+Na]+: 330.08894; found: 330.08841.

N

O

S8

1-(5-(Pyren-1-yl)pyridin-2-yl)-N-(pyridin-2-ylmethyl)methan-

amine (11). The synthesis was performed according to a modified

reported procedure.[4] Pyridin-2-ylmethanamine (0.103 mL,

1.00 mmol) was slowly added at room temperature to a solution

of 5-(pyren-1-yl)picolinaldehyde (9, 0.307 g, 1.00 mmol) in dry trimethylorthoformate (15 mL). After

stirring the solution at room temperature for one hour, the solvent was removed under high vacuum. The

obtained brownish residue (10) was then dissolved in a mixture of dichloromethane (12 mL) and

methanol (3 mL), and sodium borohydride (0.078 g, 2.07 mmol) was slowly added to the solution. The

resulting mixture was then stirred at room temperature overnight, before being poured into water

(20 mL) and adjusting the pH value to 14 by adding an aqueous solution of sodium hydroxide (10 M). The

mixture was extracted with diethylether (3 x 20 mL) and the combined organic phases were washed with

an aqueous solution of sodium hydroxide (0.5 M, 2 x 20 mL). Subsequently, an aqueous solution of citric

acid (1 M, 3 x 20 mL) was added and the pH value was then again adjusted to 14 by addition of an aqueous

solution of sodium hydroxide (10 M). The mixture was extracted with dichloromethane (3 x 20 mL). The

combined organic phases were dried over anhydrous sodium sulfate and the solvent was removed in

vacuo. The obtained residue was dried under high vacuum leading to 1-(5-(pyren-1-yl)pyridin-2-yl)-N-

(pyridin-2-ylmethyl)methanamine (11) as a yellow oil (0.350 g, 0.876 mmol, 88%). 1H-NMR (600 MHz,

CD2Cl2, 296 K): 8.82 (d, J = 2.1 Hz, 1H), 8.58 (d, J = 4.8 Hz, 1H), 8.25 (d, J = 7.8 Hz, 1H), 8.23 (dd,

J = 6.7 Hz, 0.9 Hz, 1H), 8.19 (d, J = 7.4 Hz, 1H), 8.14-8.10 (m, 3H), 8.07-8.02 (m, 2H), 7.97 (d, J = 7.8 Hz, 1H),

7.93 (dd, J = 2.3 Hz, 5.5 Hz, 1H), 7.69 (td, J = 1.9 Hz, 5.9 Hz, 1H), 7.58 (d, J = 7.8 Hz, 1H), 7.43 (d, J = 7.9 Hz,

1H), 7.20 (dd, J = 4.9 Hz, 2.6 Hz, 1H), 4.12 (s, 2H), 4.08 (s, 2H), 3.06 (br s, 1H). 13C{1H}-NMR (151 MHz,

CD2Cl2, 296 K): 160.0, 158.9, 150.7, 149.6, 138.6, 136.8, 135.4, 134.2, 131.8, 131.4, 131.3, 129.1, 128.3,

128.1, 127.7, 126.6, 125.8, 125.5, 125.3, 125.2, 125.1, 124.9, 122.6, 122.4, 122.2, 55.0, 54.8. HRMS (ESI+):

m/z: calcd. for C28H21N3 [M+H]+: 400.18082; found: 400.18088.

2-(((5-(Pyren-1-yl)pyridin-2-yl)methyl)(pyridin-2-ylmethyl)amino)-N-

(quinolin-8-yl)acetamide (H-dpaqPyr, 5d). A solution of 1-(5-(pyren-1-

yl)pyridin-2-yl)-N-(pyridin-2-ylmethyl)methanamine (11, 280 mg,

0.70 mmol) in dry dichloromethane (2 mL) was slowly added at 0 °C to a

solution of 2-Bromo-N-(quinolin-8-yl)acetamide (4a, 199 mg, 0.750 mmol)

and sodium carbonate (85 mg, 0.80 mmol) in dry acetonitrile (12 mL). The

mixture was then slowly warmed up to room temperature where it was

NNH N

NHN

NO

N

N

S9

stirred overnight and subsequently filtered over fritted glass to remove excess sodium carbonate. After

removal of the volatiles in vacuo, the crude product remained as a dark red oil and was purified via column

chromatography over silica with a mixture of ethyl acetate/methanol (gradient: 1:0 up to 9:1) as eluent.

H-dpaqPyr (5d) was obtained as a brownish solid (160 mg, 0.274 mmol, 39%). 1H-NMR (600 MHz, CD2Cl2,

296 K): 11.67 (s, 1H), 8.99 (dd, J = 1.7 Hz, 2.6 Hz, 1H), 8.80-8.77 (m, 2H), 8.56 (d, J = 4.8 Hz, 1H), 8.22

(dd, J = 2.9 Hz, 5.0 Hz, 2H), 8.19 (dd, J = 1.7 Hz, 6.6 Hz, 1H), 8.17 (dd, J = 2.5 Hz, 5.5 Hz, 2H), 8.10 (q,

J = 3.7 Hz, 8.9 Hz, 2H), 8.05 (d, J = 7.9 Hz, 1H), 8.03 (t, J = 7.6 Hz, 1H), 8.01 (q, J = 9.3 Hz, 5.2 Hz, 2H), 7.92

(dd, J = 2.3 Hz, 5.6 Hz, 1H), 7.89 (d, J = 7.8 Hz, 1H), 7.79 (td, J = 1.8 Hz, 5.9 Hz, 1H), 7.57-7.53 (m, 2H),

7.51-7.48 (m, 1H), 7.20 (dd, J = 5.0 Hz, 2.5 Hz, 1H), 4.17 (s, 2H), 4.14 (s, 2H), 3.66 (s, 2H). 13C{1H}-NMR

(151 MHz, CD2Cl2, 296 K): 169.9, 158.8, 157.6, 150.5, 149.5, 148.7, 139.2, 138.7, 136.9, 136.7, 135.7,

135.0, 134.0, 131.8, 131.4, 131.2, 129.0, 128.6, 128.3, 128.1, 128.0, 127.7, 126.6, 125.8, 125.4, 125.2,

125.1, 125.0, 124.8, 123.9, 123.4, 122.7 , 122.1, 121.0, 116.5, 61.7, 61.4, 60.0. HRMS (ESI+): m/z: calcd. for

C39H29N5O [M+H]+: 584.24449; found: 584.24445.

1.4. Synthesis of (H-dpaqCF3)

O

NHN

O

NHN

CF3

CF3

CF3

N

N

ON

HNN

OBr

HNN

NH2N

CF3

NNH2

a) b)

3d

d) e)

c)

3a

3d

4d 5f

12a 12b

Scheme S5. Reaction conditions: a) benzoylchloride, Et3N, CH2Cl2, r.t, overnight; b) NH2SO3H, PhI(OAc)2, NaSO2CF3, dichloroethane, 50 °C, 24 h; c) HCl, EtOH, 100 °C, 24 h; d) bromoacetylbromide, Na2CO3, MeCN, 0 °C, 20 min; e) bis(2-pyridylmethyl)amine, Na2CO3, MeCN, 0 °C to r.t., overnight.

N-(quinolin-8-yl)benzamide (12a). The synthesis was performed according to a

modified reported procedure.[5] A solution of benzoylchloride (700 mg, 5.0 mmol),

O

NNH

S10

8-aminoquinoline (3a, 665 mg, 4.6 mmol) and triethylamine (0.765 mL, 5.5 mmol) in dry dichloromethane

(10 mL) at room temperature was stirred overnight. Subsequently, water (10 mL) was added and the

mixture was extracted with dichloromethane (3 x 20 mL). The combined organic phases were washed with

water (20 mL) and brine (20 mL) and were dried over anhydrous sodium sulfate before the solvent was

removed in vacuo. Drying under high vacuum led to N-(quinolin-8-yl)benzamide (12a) as a brownish-grey

solid (985 mg, 3.97 mmol, 86%). The obtained analytical data are consistent with those previously

reported in the literature.[6] 1H-NMR (400 MHz, CD2Cl2, 296 K): 10.8 (s, 1H), 8.90 (dd, J = 2.0 Hz, 6.8 Hz,

1H), 8.87 (d, J = 4.0 Hz, 1H), 8.23 (d, J = 8.2 Hz, 1H), 8.08 (d, J = 7.6 Hz, 2H), 7.64-7.54 (m, 5H), 7.51 (dd,

J = 4.3 Hz, 8.3 Hz, 1H). 13C{1H}-NMR (101 MHz, CD2Cl2, 296 K): 165.5, 148.8, 139.1, 136.9, 135.6, 135.1,

132.2, 129.3, 129.2, 128.8, 128.5, 127.7, 127.6, 122.2, 122.1, 116.7.

N-(5-(Trifluoromethyl)quinolin-8-yl)benzamide (12b). The synthesis was

performed according to a modified reported procedure.[5] A mixture of N-(quinolin-

8-yl)benzamide (12a, 2.48 g, 10.0 mmol), sodium trifluoromethanesulfinate

(6.24 g, 20.0 mmol), diacetoxyiodobenzene (6.44 g, 20.0 mmol), sulfamic acid

(6.44 g, 20.0 mmol) and dichloroethane (50 mL) was stirred at 50 °C for 24 h. After

cooling down to room temperature, the mixture was diluted with dichloromethane (25 mL) and filtered

over celite. The filter cake was washed with dichloromethane (3 x 8 mL) and the solvent of the filtrate was

removed in vacuo. The resulting crude product was purified by column chromatography over silica with a

mixture of petrol ether/ethyl acetate (1:1) as eluent. N-(5-(trifluoromethyl)quinolin-8-

yl)benzamide (12b) was obtained as a brownish-grey solid (670.5 mg, 2.12 mmol, 21%). The obtained

analytical data are consistent with those previously reported in the literature.[5] 1H-NMR (400 MHz, CD2Cl2,

296 K): 10.9 (s, 1H), 8.99-8.92 (m, 2H), 8.54 (d, J = 8.7 Hz, 1H), 8.09 (d, J = 7.6 Hz, 2H), 7.98 (d,

J = 8.3 Hz, 1H), 7.69-7.55 (m, 5H). 13C-APT-NMR (101 MHz, CD2Cl2, 296 K): 165.8, 149.3, 139.0, 138.2,

135.0, 133.5, 132.6, 128.9, 128.0, 127.7, 127.0 (q, J = 5.8 Hz), 126.2, 124.7, 123.5, 119.6, 114.2. 19F{1H}-NMR (377 MHz, CD2Cl2, 296 K): -59.0.

5-(Trifluoromethyl)quinolin-8-amine (3d). The synthesis was performed according to a

modified reported procedure.[5] Concentrated hydrochloric acid (5.3 mL) was added to a

solution of N-(5-(trifluoromethyl)chinolin-8-yl)benzamide (12b, 670.5 mg, 2.12 mmol) in

ethanol (14 mL). The solution was stirred at 100 °C for 24 h. After that time, the reaction

mixture was cooled down to room temperature, concentrated in vacuo and an aqueous

solution of sodium hydroxide (3 M) was added until the basic pH range was reached. The product was

O

NNH

CF3

NNH2

CF3

S11

extracted with dichloromethane (3 x 20 mL) and the combined organic phases were dried over anhydrous

sodium sulfate. After removal of the volatiles in vacuo, the crude product was further purified via column

chromatography on silica with a mixture of dichloromethane/ethyl acetate (gradient: 9:1 up to 1:1) as

eluent. 5-(Trifluoromethyl)quinolin-8-amine (3d) was obtained as a brownish-grey solid (137.9 mg,

0.650 mmol, 31%). The obtained analytical data are consistent with those previously reported in the

literature.[5] 1H-NMR (400 MHz, CDCl3, 296 K): 8.83 (d, J = 4.2 Hz, 1H), 8.51 (d, J = 8.8 Hz, 1H), 7.73 (d,

J = 8.1 Hz, 1H), 7.58 (dd, J = 4.3 Hz, 8.6 Hz, 1H), 6.88 (d, J = 8.1 Hz, 1H), 5.84 (br-s, 2H). 13C-APT-NMR (101 MHz, CDCl3, 296 K): 147.4, 147.2, 133.7, 127.2 (q, J = 5.7 Hz), 126.3, 125.5, 123.6,

122.6, 107.3. 19F{1H}-NMR (377 MHz, CDCl3, 296 K): -57.9.

2-Bromo-N-(5-(trifluoromethyl)quinolin-8-yl)acetamide (4d). Bromoacetylbromide

(68.2 µL, 0.78 mmol) was slowly added at 0 °C to a solution of 5-

(trifluoromethyl)quinolin-8-amine (3d, 138 mg, 0.65 mmol) and sodium

carbonate (96.2 mg, 0.91 mmol) in dry acetonitrile (10 mL). The reaction mixture was

stirred at 0 °C for 20 min before the fine dispersed solid was recovered by filtration.

The obtained solid was washed with acetonitrile (3 mL) and diethylether (10 mL), before drying under high

vacuum led to 2-Bromo-N-(5-(trifluoromethyl)quinolin-8-yl)acetamide (4d) as a grey solid (198 mg,

0.59 mmol, 91%). 1H-NMR (300 MHz, CD3CN, 296 K): 11.0 (s, 1H), 9.25 (dt, J = 8.8 Hz, J = 1.5 Hz, 1H),

9.16 (dd, J = 5.3 Hz, J = 1.5 Hz, 1H), 8.87 (d, J = 8.5 Hz, 1H), 8.32 (d, J = 8.5 Hz, 1H), 8.22 (dd,

J = 8.8 Hz, 5.3 Hz, 1H), 4.52 (s, 2H). 19F{1H}-NMR (377 MHz, CD2Cl2, 296 K): -59.2. HRMS (ESI+): m/z:

calcd. for C12H9F3N2BrO [M+H]+: 332.98449; found: 332.98445.

2-(Bis(pyridin-2-ylmethyl)amino)-N-(5-(trifluoromethyl)quinolin-8-

yl)acetamide (H-dpaqCF3, 5f). Bis(2-pyridylmethyl)amine (103 µL, 0.57 mmol)

was slowly added at 0 °C to a mixture of 2-bromo-N-(5-

(trifluoromethyl)quinolin-8-yl)acetamide (4d, 198 mg, 0.60 mmol) and sodium

carbonate (68 mg, 0.64 mmol) in dry acetonitrile (9 mL). The mixture was then

slowly warmed up to room temperature and stirring was continued overnight.

The resulting mixture was filtered over fritted glass to remove excess sodium carbonate. The solvent of

the filtrate was removed in vacuo and the obtained residue was dried under high vacuum leading to

H-dpaqCF3 (5f) as a red solid (75 mg, 0.17 mmol, 26%) which was used without further purification.

1H-NMR (400 MHz, CD3CN, 296 K): 11.7 (s, 1H), 9.10 (d, J = 4.1 Hz, 1H), 8.68 (d, J = 8.2 Hz, 1H), 8.55

(dt, J = 1.9 Hz, 8.8 Hz, 1H), 8.47 (d, J = 4.7 Hz, 2H), 7.95 (d, J = 8.2 Hz, 1H), 7.84 (d, J = 7.7 Hz, 2H), 7.76 (dd,

NHN

BrO

CF3

NHN

NO

N

N

CF3

S12

J = 4.1 Hz, 8.7 Hz, 1H), 7.68 (dt, J = 1.7 Hz, 7.7 Hz, 2H), 7.17 (dd, J = 5.4 Hz, 7.0 Hz, 2H), 3.97 (s, 4H), 3.54 (s,

2H). 13C-APT-NMR (101 MHz, CD3CN, 296 K): 171.3, 159.3, 150.5, 150.0, 137.5, 129.3, 133.6, 127.6 (q,

J = 6.0 Hz), 124.5, 123.4, 118.3, 114.3, 61.9, 60.3. 19F{1H}-NMR (377 MHz, CD3CN, 296 K): -59.3.

HRMS (ESI+): m/z: calcd. for C24H20F3N5O [M+Na]+: 474.15122; found: 474.14902.

2. Supporting Figures

2.1. NMR spectra

-1.0-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0δ(ppm)

3.09

2.05

0.97

0.93

1.01

0.98

1.00

3.88

5.01

6.48

6.48

6.58

6.59

7.26

CD

Cl3

7.31

7.32

7.33

7.34

7.95

7.95

7.97

7.97

8.59

8.59

8.60

8.60

Figure S1. 1H-NMR spectrum (400 MHz, CDCl3, 296 K) of 5-Methoxyquinolin-8-amine (3b).

NNH2

OMe

S13

-100102030405060708090100110120130140150160170180190200210δ(ppm)

55.9

0

76.8

477

.16

77.4

8

105.

41

109.

76

120.

4212

1.13

130.

8113

7.40

139.

11

147.

0014

8.07

Figure S2. 13C-APT-NMR spectrum (101 MHz, CDCl3, 296 K) of 5-Methoxyquinolin-8-amine (3b).

-1.0-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5δ(ppm)

3.03

2.03

0.99

0.95

1.00

1.00

1.01

2.04

3.30

MeO

D3.

31 M

eOD

3.31

MeO

D3.

31 M

eOD

3.32

MeO

D

4.04

4.26

4.88

HD

O

7.61

7.62

7.80

7.81

7.99

8.00

8.01

8.02

8.94

8.95

8.95

8.96

8.99

9.00

9.01

Figure S3. 1H-NMR spectrum (400 MHz, CD3OD, 296 K) of 2-bromo-N-(6-methoxyquinolin-8-yl)acetamide (4c).

NHN

BrO

OMe

NNH2

OMe

S14

-100102030405060708090100110120130140150160170180δ(ppm)

29.1

9

48.3

6 M

eOD

48.5

8 M

eOD

48.7

9 M

eOD

49.0

0 M

eOD

49.2

1 M

eOD

49.4

3 M

eOD

49.6

4 M

eOD

56.9

7

105.

89

122.

8112

3.69

132.

0113

2.72

139.

9814

3.75

145.

57

161.

24

169.

15

Figure S4. 13C-APT-NMR spectrum (101 MHz, CD3OD, 296 K) of 2-bromo-N-(6-methoxyquinolin-8-yl)acetamide (4c).

-1.00.01.02.03.04.05.06.07.08.09.010.011.012.0δ(ppm)

1.93

2.96

4.67

0.98

2.42

1.09

2.40

2.02

1.00

0.94

1.99

1.00

0.87

1.92

2.80

HD

O

3.45

3.82

3.92

6.73

6.74

7.06

7.06

7.07

7.08

7.08

7.08

7.09

7.10

7.26

CD

Cl3

7.37

7.38

7.39

7.40

7.56

7.57

7.58

7.58

7.60

7.60

7.88

7.90

7.98

7.98

8.00

8.00

8.38

8.39

8.43

8.44

8.70

8.70

8.71

8.71

11.4

7

Figure S5. 1H-NMR spectrum (400 MHz, CDCl3, 296 K) of H-dpaq6-OMe (5c).

NHN

BrO

OMe

NHN

NO

N

N

OMe

S15

-100102030405060708090100110120130140150160170180δ(ppm)

55.4

459

.18

60.9

3

99.7

1

108.

83

122.

0512

2.32

123.

34

128.

9713

4.91

135.

0713

5.28

136.

57

145.

48

148.

93

157.

9815

8.27

169.

50

Figure S6. 13C-APT-NMR spectrum (101 MHz, CDCl3, 296 K) of H-dpaq6-OMe (5c).

-1.00.01.02.03.04.05.06.07.08.09.010.0δ(ppm)

1.00

2.03

1.02

3.80

1.02

1.02

1.03

0.96

0.94

5.32

CD

2Cl2

5.32

CD

2Cl2

5.32

CD

2Cl2

7.98

7.99

8.05

8.05

8.06

8.07

8.07

8.09

8.11

8.12

8.13

8.14

8.14

8.15

8.17

8.21

8.21

8.21

8.22

8.23

8.25

8.25

8.26

8.26

8.27

8.29

9.05

9.06

9.06

10.2

1

Figure S7. 1H-NMR spectrum (600 MHz, CD2Cl2, 296 K) of 5-(pyren-1-yl)picolinaldehyde (9).

N

O

NHN

NO

N

N

OMe

S16

-100102030405060708090100110120130140150160170180190200δ(ppm)

53.4

853

.66

53.8

454

.02

54.2

0

121.

5712

4.32

124.

9612

5.27

125.

7912

6.16

126.

8012

7.66

127.

9312

8.63

128.

8712

9.01

131.

2013

1.79

132.

0213

2.81

139.

1314

1.59

151.

9215

2.05

193.

61

Figure S8. 13C{1H}-NMR spectrum (151 MHz, CD2Cl2, 296 K) of 5-(pyren-1-yl)picolinaldehyde (9).

-1.0-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0δ(ppm)

1.39

1.90

1.87

1.03

0.98

0.96

1.04

1.04

1.00

2.24

2.93

1.03

1.08

1.07

0.94

0.91

3.06

4.08

4.12

5.32

CD

2Cl2

5.32

CD

2Cl2

5.32

CD

2Cl2

7.19

7.19

7.20

7.21

7.42

7.44

7.57

7.58

7.67

7.68

7.69

7.69

7.70

7.70

7.92

7.92

7.93

7.93

7.96

7.97

8.02

8.04

8.05

8.07

8.10

8.11

8.12

8.13

8.18

8.20

8.22

8.23

8.24

8.25

8.58

8.59

8.82

8.82

Figure S9. 1H-NMR spectrum (600 MHz, CD2Cl2, 296 K) of 1-(5-(pyren-1-yl)pyridin-2-yl)-N-(pyridin-2-ylmethyl)methanamine (11).

N

O

NNH N

S17

-100102030405060708090100110120130140150160170180δ(ppm)

53.4

853

.66

53.8

454

.02

54.2

054

.77

54.9

7

122.

1612

2.35

122.

6012

4.92

125.

0612

5.16

125.

2512

5.44

125.

5512

5.75

126.

5912

7.70

128.

0712

8.10

128.

2712

9.10

131.

2813

1.41

131.

8213

4.20

135.

3713

6.76

138.

5614

9.61

150.

70

158.

8916

0.01

Figure S10. 13C{1H}-NMR spectrum (151 MHz, CD2Cl2, 296 K) of 1-(5-(pyren-1-yl)pyridin-2-yl)-N-(pyridin-2-ylmethyl)methanamine (11).

-1.00.01.02.03.04.05.06.07.08.09.010.011.012.0δ(ppm)

1.99

2.00

1.98

1.01

1.01

2.03

1.01

0.99

0.99

1.83

1.31

1.04

2.11

2.03

1.09

1.95

0.96

1.93

0.93

0.90

3.66

4.14

4.17

7.19

7.20

7.20

7.21

7.48

7.49

7.50

7.50

7.53

7.54

7.55

7.55

7.56

7.70

7.70

7.71

7.71

7.72

7.73

7.88

7.89

7.91

7.92

7.93

7.93

7.99

8.00

8.01

8.03

8.04

8.05

8.06

8.08

8.10

8.10

8.12

8.16

8.17

8.18

8.18

8.19

8.19

8.20

8.20

8.21

8.21

8.22

8.22

8.56

8.57

8.78

8.79

8.79

8.80

8.80

8.98

8.99

8.99

8.99

11.6

7

Figure S11. 1H-NMR spectrum (600 MHz, CD2Cl2, 296 K) of H-dpaqPyr (5d).

NNH N

NHN

NO

N

N

S18

-100102030405060708090100110120130140150160170180δ(ppm)

53.4

853

.66

53.8

454

.02

54.2

054

.77

54.9

7

122.

1612

2.35

122.

6012

4.92

125.

0612

5.16

125.

2512

5.44

125.

5512

5.75

126.

5912

7.70

128.

0712

8.10

128.

2712

9.10

131.

2813

1.41

131.

8213

4.20

135.

3713

6.76

138.

5614

9.61

150.

70

158.

8916

0.01

Figure S12. 13C{1H}-NMR spectrum (151 MHz, CD2Cl2, 296 K) of H-dpaqPyr (5d).

-1.00.01.02.03.04.05.06.07.08.09.010.011.0δ(ppm)

2.04

1.00

1.01

0.99

1.00

0.99

0.80

1.92

CD

3CN

1.93

CD

3CN

1.94

CD

3CN

1.95

CD

3CN

1.96

CD

3CN

1.96

2.32

HD

O

4.52

8.20

8.21

8.23

8.24

8.31

8.34

8.85

8.88

9.15

9.16

9.17

9.18

9.23

9.23

9.24

9.26

9.26

9.27

11.0

3

Figure S13. 1H-NMR spectrum (300 MHz, CD3CN, 296 K) of 2-Bromo-N-(5-(trifluoromethyl)quinolin-8-yl)acetamide (4d).

NHN

NO

N

N

NHN

BrO

CF3

S19

-78-76-74-72-70-68-66-64-62-60-58-56-54-52-50-48-46-44-42-40δ(ppm)

-59.

18

Figure S14. 19F{1H}-NMR spectrum (377 MHz, CD3CN, 296 K) of 2-Bromo-N-(5-(trifluoromethyl)quinolin-8-yl)acetamide (4d).

-1.00.01.02.03.04.05.06.07.08.09.010.011.012.0δ(ppm)

1.98

4.05

2.00

1.03

2.04

2.07

2.05

1.01

1.96

1.00

1.00

0.67

1.93

CD

3CN

1.93

CD

3CN

1.94

CD

3CN

1.95

CD

3CN

1.95

CD

3CN

2.15

HD

O2.

17 H

DO

3.50

3.95

7.17

7.18

7.19

7.20

7.51

7.53

7.55

7.59

7.59

7.59

7.60

7.61

7.61

7.61

7.62

7.68

7.68

7.69

7.70

7.71

7.72

7.89

7.91

8.30

8.31

8.32

8.33

8.46

8.47

8.64

8.64

8.66

8.66

9.00

9.01

9.01

9.02

11.4

6

Figure S15. 1H-NMR spectrum (400 MHz, CD3CN, 296 K) of H-dpaqCF3 (5f).

NHN

NO

N

N

CF3

NHN

BrO

CF3

S20

-100102030405060708090100110120130140150160170180δ(ppm)

0.70

0.91

1.12

CD

3CN

1.32

CD

3CN

1.52

CD

3CN

1.73

1.94

55.0

060

.29

61.9

1

114.

2911

8.32

122.

9912

3.09

123.

3712

4.51

127.

5812

7.64

133.

6713

7.56

139.

3313

9.45

150.

0215

0.48

159.

26

171.

30

Figure S16. 13C-APT-NMR spectrum (101 MHz, CD3CN, 296 K) of H-dpaqCF3 (5f).

-82-80-78-76-74-72-70-68-66-64-62-60-58-56-54-52-50-48-46-44-42-40δ(ppm)

-59.

31

Figure S17. 19F{1H}-NMR spectrum (377 MHz, CD3CN, 296 K) of H-dpaqCF3 (5f).

NHN

NO

N

N

CF3

NHN

NO

N

N

CF3

S21

2.2. Electrochemistry

Figure S18. Left: CV of [Fe(dpaq5-NO2)](ClO4)2 (1e) with increasing concentration (0.50 – 2.00 mM) in PC (3.2 vol% H2O (1.85 M), 200 mM LiClO4) at a scan rate of 75 mV/s with subtracted background. Right: Plot of icat vs. the concentration of 1e.

Figure S19. CV of [Fe(dpaq5-H)(H2O)](ClO4)2 (1a, red) and [Fe(dpaq6-OMe)(H2O)](ClO4)2 (1c, black) (both 1.0 mM) in PC (3.2 vol% H2O (1.85 M), 200 mM LiClO4) at a scan rate of 75 mV/s.

S22

Figure S20. CV of [Fe(dpaqPyr)](ClO4)2 (1d) with increasing concentration from 0.5 mM (black), 1.0 mM (red) up to 1.5 mM (blue) in PC (3.2 vol% H2O (1.85 M), 200 mM LiClO4) at a scan rate of 75 mV/s.

Figure S21. Left: CV after 50 scans of [Fe(dpaqPyr)](ClO4)2 (1d) with increasing concentration from 0.5 mM (black), 1.0 mM (red) up to 1.5 mM (blue) in PC (3.2 vol% H2O (1.85 M), 200 mM LiClO4) at a scan rate of 75 mV/s. Right: 50 successive CVs of 1d (0.5 mM) in PC (3.2 vol% H2O (1.85 M), 200 mM LiClO4) at a scan rate of 75 mV/s.

S23

Figure S22. CV of [Mn(dpaqH)]ClO4 (2a, 1.0 mM) in acetonitrile with 100 mM (n-Bu)4N(ClO4) at a scan rate of 300 mV/s.

Figure S23. Left: CV of [Mn(dpaqH)]ClO4 (2a, 1.0 mM) in acetonitrile with 100 mM (n-Bu)4N(ClO4) and an increasing amount of water at a scan rate of 50 mV/s. Right: Plot of icat² vs. the concentration of water.

S24

Figure S24. Left: CV of [Mn(dpaqH)]ClO4 (2a) with increasing concentration in acetonitrile with 100 mM (n-Bu)4N(ClO4) and 7 vol% water (4.05 M) at a scan rate of 50 mV/s. Right: Plot of icat vs. the concentration of 2a.

Figure S25. Left: CV of [Mn(dpaqH)]ClO4 (2a, 1.0 mM) in borate buffer (0.2 M, pH 8) with increasing scan rate. Right: Normalized current (i/ν0.5) vs. potential.

S25

Figure S26. Pourbaix diagram for MnIII-OH/MnIV=O (1.0 mM) of 2a in a borate buffer (0.2 M).

Figure S27. CV of [Mn(dpaqH)]ClO4 (2a, red) and of [Mn(dpaqPyr)]ClO4 (2d, black) (both 1.0 mM) in PC (3.2 vol% H2O (1.85 M), 200 mM LiClO4) at a scan rate of 75 mV/s.

S26

References

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