Supporting Information
Insight into One-Electron Oxidation of the {Fe(NO)2}9 Dinitrosyl Iron Complex (DNIC): Aminyl Radical Stabilized by [Fe(NO)2] Motif
Chih-Chin Tsou,† Fu-Te Tsai,† Huang-Yeh Chen,‡ I-Jui Hsu,*, ‡ and Wen-Feng Liaw*,† †
Department of Chemistry, National Tsing-Hua University, Hsinchu, 30013, Taiwan.
‡
Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei 10608 Taiwan.
E-mail:
[email protected]; E-mail:
[email protected] Table S1. The IR νNO of the reversible redox {Fe(NO)2}9 and {Fe(NO)2}10 DNICs. {Fe(NO)2}10 {Fe(NO)2}9 {Fe(NO)2}9 {Fe(NO)2}10 ∆νNO –1 –1 νNO cm νNO cm cm–1 1808, 1687, 121 + + e NO 1739 (THF) 1633 (THF) 106 NO N N Fe Fe N N 1814, 1679, 135 -e NO NO 1746 (MeCN) 1622 (MeCN) 124 1815, 1686, 129 + N N N + e NO 1741 (THF) 1632 (THF) 109 NO N Fe Fe N 1673 N NO NO -e N N 1616 (CH2Cl2) N
+
N
NO
N
NO Fe
e-
-
NO
NO
N
+
N iPr N
+ e-
NO Fe
iPr
-e
NO
N N
-
NO Fe
iPr
NO
N N
+
NO Fe
+ e-
NO Fe NO
Ph3 P
_ iPr
iPr N
NO
+ e-
NO
- e-
Fe N iPr
iPr
iPr
iPr
N Fe
NO
N iPr
NO
+ e-
EtS
NO
- e-
EtS
2
NO
_
Fe
Fe EtS
NO
iPr
_
NO
_ N S S
NO
+ e-
NO
-
Fe
-e
S
2
N S N
NO
S S
Fe NO
S
_ N
O
N S
a
2
S
S O
1667, 1624 (THF)
122 109
4f
1791, 1723 (THF)
1664, 1619 (THF)
127 104
4f
1814, 1766 (CH2Cl2)
1714, 1668 (CH2Cl2)
100 98
4a
1761, 1709 (C6D6) 1755, 1705 (KBr) 1715, 1674 (THF) 1721, 1676 (KBr) 1773, 1721 (MeCN) 1768, 1729 (KBr) 1791, 1723 (MeCN) 1786, 1696 (KBr)
1627, 1567 (C6D6) 1632, 1559 (KBr) 1614, 1571 (THF) 1604, 1560 (KBr) 1684, 1633 (MeCN) 1654, 1609 (KBr) 1665, 1609 (MeCN) 1664, 1606 (KBr)
134 142 123 146 101 103 117 116 89 88 114 120 126 114 122 90
iPr
Ph 3P
e-
-
NO
Ph3 P
S N
1789, 1733 (THF)
N iPr N
iPr
iPr
Ph 3P
EtS
this work, 4b
N
N
iPr
4c
N
+ e-
Fe N
Ref. a
NO Fe NO
+e
-
-e
-
O
N
O
N
NO Fe
S
References are shown in the text.
NO
_
_
4d
5f, 8
4e
4e
Table S2. Comparisons of different exchange functionals results on complex 5.
Table S3. IR vibrational frequencies of experimental and B3LYP* results. νNO (cm–1) Complex 4 5
Expt. Symmetry 1707 1786
Asymmetry 1652 1733
B3LYP* Symmetry Asymmetry 1724.43 1673.73 1828.96 1770.88
Table S4 Summary of crystal data, intensity collection and structure refinement parameters for [(NO)2Fe(NPh2)2]– (2), [(NO)2Fe(N(TMS)2)2]– (3), [(NO)2Fe(N(mesityl)-(TMS))2]– (4) and [(NO)2Fe(N(mesityl)(TMS))2] (5). Complex number
2
Chemical formula
C32H36 FeKN4O9•2(C4H8O)
C24H60FeKN4O8Si4
C44H80FeKN4O10Si2•2(C4H8O)
C24H40FeN4O2Si2
Formula Mass
899.92
740.07
976.25
528.63
3
4
5
Crystal system
Monoclinic
Monoclinic
Orthorhombic
Orthorhombic
a/Å
14.256(3)
23.2705(8)
15.8975(9)
13.1256(10)
b/Å
13.064(3)
15.7542(6)
22.4576(12)
11.3614(9)
c/Å
24.449(5)
24.0988(9)
30.9214(17)
19.5259(14)
α/°
90.00
90.00
90.00
90.00
β/°
95.777(4)
111.731(2)
90.00
90.00
γ/°
90.00
90.00
90.00
90.00
Unit cell volume/Å3
4530.4(16)
8206.9(5)
11039.5(11)
2911.8(4)
Temperature/K
200(2)
200(2)
200(2)
200(2)
Space group
P 2/c
P 21/n
Pbca
Pnna
No. of formula units per unit cell, Z
4
8
8
4
Radiation type Synchrotron
MoKα
MoKα
MoKα
MoKα 0.626
Absorption coefficient, µ/mm
-1
0.477
0.627
0.443
No. of reflections measured
26327
54135
62208
14571
No. of independent reflections
7925
14412
9717
2570
Rint
0.0704
0.0738
0.0656
0.0430
Final R1 values (I > 2σ(I))
0.0619
0.0770
0.0505
0.0435
Final wR(F2) values (I > 2σ(I))
0.1540
0.2042
0.1194
0.1146
Final R1 values (all data)
0.1161
0.1374
0.0860
0.0603
Final wR(F2) values (all data)
0.1722
0.2275
0.1386
0.1268
Goodness of fit on F2
0.966
1.099
1.014
1.023
CCDC number
CCDC-876478
CCDC-876479
CCDC-876480
CCDC-876481
Scheme S1. One-electron oxidation of thiolate-coordinate {Fe(NO)2}9 DNICs, presumably, occurs from thiolate ligands to yield [{Fe(NO)2}9-(SR)2–•] intermediate, followed by dimerizing to yield [(NO)2Fe(µ-SR)]2 and disulfide.
Figure S1. ORTEP drawing and labeling scheme of [(NO)2Fe(NPh2)2]– (2) in [(THF)2-K18-crown-6-ether)]+ salt with thermal ellipsoids drawn at 50 % probability. Selected bond distances (Ǻ) and angles (deg): Fe(1)-N(1) 1.689(3), Fe(1)-N(2) 1.693(4), Fe(1)-N(3) 1.983(3), Fe(1)-N(4) 1.973(3), N(1)-O(1) 1.178(4), N(2)-O(2) 1.163(4), N(1)-Fe(1)-N(2) 110.73(17), N(3)-Fe(1)-N(4) 109.75(12), Fe(1)-N(1)-O(1) 161.7(3), Fe(1)-N(2)-O(2) 163.9(4).
Figure S2. ORTEP drawing and labeling scheme of [(NO)2Fe(N(TMS)2)2]– (3) in [K-18crown-6-ether)]+ salt with thermal ellipsoids drawn at 30 % probability. Selected bond distances (Ǻ) and angles (deg): Fe(1)-N(1) 1.700(6), Fe(1)-N(2) 1.686(6), Fe(1)-N(3) 2.010(5), Fe(1)-N(4) 1.971(5), N(1)-O(1) 1.190(7), N(2)-O(2) 1.152(8), N(3)-Si(1) 1.683(6), N(3)-Si(2) 1.709(6), N(4)-Si(3) 1.708(5), N(4)-Si(4) 1.713(6), K(1)-O(1) 2.778(6), Fe(2)N(5) 1.706(7), Fe(2)-N(6) 1.695(7), Fe(2)-N(7) 2.009(6), Fe(2)-N(8) 1.976(5), N(5)-O(16) 1.184(8), N(6)-O(16) 1.175 (8), N(7)-Si(5) 1.701(6), N(7)-Si(6) 1.712(6), N(8)-Si(7) 1.704(5), N(8)-Si(8) 1.712(5), N(1)-Fe(1)-N(2) 110.5(3), N(3)-Fe(1)-N(4) 117.5(2), Fe(1)N(1)-O(1) 152.1(7), Fe(1)-N(2)-O(2) 170.0(6), N(5)-Fe(2)-N(6) 104.2(3), N(7)-Fe(2)-N(8) 116.1(2), Fe(2)-N(5)-O(15) 150.9(7), Fe(2)-N(6)-O(16) 163.0(7).
(a)
3390
(b)
3400
3410
3420
3430
3440
3450
3360
3380
3400
Field [G]
3420
3440
3460
3480
3500
Field [G]
Figure S3. X-band EPR spectra of complex 2 in THF (a) at 298 K (solid line) and the simulation curve (dash line) with gav = 2.019 and AN(NO) = 2.40 G, AN(amide) = 4.64 G; (b) at 77K with g1 = 2.023, g2 = 2.016, g3 = 2.010.
(a)
3390
(b)
3400
3410
3420
Field [G]
3430
3440
3360
3380
3400
3420
3440
3460
3480
Field [G]
Figure S4. X-band EPR spectra of complex 3 in THF (a) at 298 K (solid line) and the simulation curve (dash line) with gav = 2.020 and AN(NO) = 2.45 G, AN(amide) = 3.75 G; (b) at 77K with g1 = 2.024, g2 = 2.017, g3 = 2.011.
(a)
(b) 2.0
0.20
1.8 1.6 0.15 1.4 1.2
χM
µeff
0.10
1.0 0.8 0.6
0.05 0.4 0.2 0.0
0.00 0
50
100
150
200
250
300
0
50
100
150
200
250
T(K)
T (K) (c) 0.5 data fit 0.4
0.3
χMT
0.2
Data: Data1_B Model: user29 Chi^2/DoF = 2.3855E-6 R^2 = 0.99274
0.1
P1 P2 P3
2.049 ±--0.14625 2.25765
±0.00543 ±0.01329
0.0 0
50
100
150
200
250
300
T (K) Figure S5. (a) The magnetic susceptibility (χM) of complex 4 under 0.5 Tesla applied field. (b) Effective magnetic moment (µeff) vs temperature (T) plot. (c) Curie Law fitting of χMT vs T plot gives g = 2.049, θ = –0.146 ± 0.005 K and TIP = (226 ± 1.3) × 10-6 cm3 mol-1 (R2 = 0.993).
300
(a) 10
Current (µA)
5
0
-5
-10
-15 -0.2
-0.4
-0.6
-0.8
-1.0
-1.2
+
Potential vs Fc /Fc (V)
(b)
30 20 10
Current (µA)
0 -10 -20 -30 -40 -50 -60 0.5
0.0
-0.5
-1.0
-1.5
-2.0
+
Potential vs Fc /Fc (V)
Figure S6. (a) Cyclic voltammogram of DNIC 2 in a 20 mM THF with 0.2 M [nBu4N][PF6] as the supporting electrolyte at room temperature and scan rate of 100 mV/s showing a psuedo-reversible redox wave with E1/2 = –0.581 V and ipa/ipc = 0.80. (b) Cyclic voltammogram of DNIC 3 in the same condition showing an oxidation wave at –0.270 V.
(a)
(b)
1.4
2
270 nm
1
265 nm
315 nm
1
Abs
Abs
318 nm 340 nm
0.5
465 516 nm nm 380 nm
0 -0.1 240
400
760 nm
600
800
495 nm
1000
-0.1 250
1200
400
Wavelength [nm]
630 nm
600
800
1000
1200
Wavelength [nm]
(c)
(d) 0.75
1.5
269 nm
0.6 624 nm 664 nm
1285 nm
0.4
374 nm
Abs
Abs 0.5
380 nm
0.2
942 nm
442 nm
0 250
634 nm
400
600
800
Wavelength [nm]
1000
1200
0 265
400
600
800
1000
Wavelength [nm]
Figure S7. UV-vis spectra of (a) [(NO)2Fe(NPh2)2]– (2), (b) [(NO)2Fe(N(TMS)2)2]– (3), (c) [(NO)2Fe(N(mesityl)(TMS))2]– (4) and (d) [(NO)2Fe(N(mesityl)(TMS))2] (5) in THF.
Figure S8. Fe K-edge spectra of complexes 2, 3 and 4 (complex 2, 7113.8 eV; complex 3, 7113.9 eV; complex 4, 7113.9 eV) (the pre-edge absorption spectra are enlarged in the inset).
1200
(a)
(b)
(c)
(d)
(f)
(e)
(g)
(i)
(h)
(j)
(k)
(l)
Figure S9. 15N NMR spectra of [Fe(µ-SEt)(15NO)2]2 (a) in D8-THF and (b) in CD3CN; 15N NMR spectra of [(15NO)2Fe(sparteine)] (c) in D8-toluene, (d) in D8-THF and (e) in CD3CN; (f) [(TMEDA)Fe(15NO)2] in D8-THF; (g) [(EtS)2Fe(15NO)2]2– in D8-THF; (h) [(EtS)2Fe(15NO)2]2– in CD3CN; (i) [Fe(µ-SEt)(15NO)2]22– in CD3CN; (j) [Fe(µStBu)(15NO)2]22– in CD3CN; 15N NMR spectra of complex 5 (k) in D8-toluene and (l) in D8THF. Peak at -132 ppm is assigned to solvent CD3C15N.
Figure S10. 1H NMR spectrum of [(NO)2Fe(N(mesityl)(TMS))2] (5) in D8-toluene.
(a)
(b) 0.65
0.0030
0.60
0.0025
0.55
0.0020
χM
µeff
0.0015
0.50
0.45
0.0010 0.40
0.0005 0.35
0.0000 0
50
100
150
200
250
0.30
300
0
50
100
T (K)
(c)
150
200
250
T(K)
0.055 0.050 0.045 0.040 0.035
χMT
0.030
Data: Data1_B Model: user5
0.025
Chi^2/DoF = 1.9664E-8 R^2 = 0.99969
0.020
P1 P2 P3 P4 P5 P6
0.015 0.010 0.005
2.015 ±-2 ±-2647.34096 0.03192 -4.44991 0.81792
±97.52167 ±0.00007 ±0.0551 ±0.00367
0.000 0
50
100
150
200
250
300
T (K) Figure S11. (a) The magnetic susceptibility of complex 5 under 0.5 T applied field, (b) effective magnetic moment (µeff) vs temperature (T) plot, and (c) the best fit gives g({Fe(NO)2}9) = 2.015, g(L•) = 2.000, ∆S/T = 1840 ± 68 cm–1, θ = –4.45 ± 0.06 K, p = 3.19 % and TIP = (81.8 ± 0.4) × 10–6 cm3 mol–1 (R2 = 0.999).
300
Figure S12. Frontier MO diagram of complex 4. Numbers shown are the compositions of Fe 3d, NO 2p and N ([N(mesityl)(TMS)]-coordinated ligands) 2p orbitals in each MO.
Figure S13. Frontier MO diagram of complex 5. Numbers shown are the compositions of Fe 3d, NO 2p and N ([N(mesityl)(TMS)]-coordinated ligands) 2p orbitals in each MO.
