Electronic Supplementary Material (ESI) for ChemComm.
This journal is © The Royal Society of Chemistry 2014
Supporting Information to
Synthesis and Ligand-Based Reduction Chemistry of Boron
Difluoride Complexes with Redox-Active Formazanate Ligands
Mu-Chieh Chang and Edwin Otten*
Stratingh Institute for Chemistry, University of Groningen, The Netherlands
Contents
Experimental Section................................................................................................................................2
X-ray crystallography ................................................................................................................................5
EPR spectrum of 3a...................................................................................................................................8
UV-VIS data for compounds 2a and 3a.....................................................................................................9
NMR spectra for compounds 1b, 2a, 4b and 2b. ....................................................................................10
References ..............................................................................................................................................17
1
Experimental Section
General Considerations.
All manipulations were carried out under nitrogen atmosphere using standard glovebox, Schlenk, and
vacuum-line techniques. Toluene and hexane (Aldrich, anhydrous, 99.8%) were passed over columns of
Al2O3 (Fluka), BASF R3-11-supported Cu oxygen scavenger, and molecular sieves (Aldrich, 4 Å). THF
(Aldrich, anhydrous, 99.8%) was dried by percolation over columns of Al2O3 (Fluka). All solvents were
degassed prior to use and stored under nitrogen. C6D6 (Aldrich) and d8-toluene (Aldrich) was vacuum
transferred from Na/K alloy and stored under nitrogen. The compounds (PhNNC(p-tolyl)NNPh)2Zn (1a)
and [MesN2]+[BF4]- were synthesized according to published procedures.1 NMR spectra were recorded on
a Varian Gemini 400 spectrometer. The 1H and 13C NMR spectra were referenced internally using the
residual solvent resonances and reported in ppm relative to TMS (0 ppm); J is reported in Hz. Elemental
analyses were performed at the Microanalytical Department of the University of Groningen or Kolbe
Microanalytical Laboratory (Mülheim an der Ruhr, Germany). UV-Vis spectra were recorded in THF
solution (~ 10-5 M) using a Perkin Elmer Lambda 900 in a quartz cell that was sealed under N2
atmosphere. EPR spectra were recorded on a Bruker EMXplus spectrometer at 20 K in THF. All
electrochemical measurements were performed under an inert N2 atmosphere in a glove box using an
Autolab PGSTAT 100 computer-controlled potentiostat. Cyclic voltammetry (CV) was performed using a
three-electrode configuration comprising of a Pt wire counter electrode, a Ag wire pseudoreference
electrode and a Pt disk working electrode (CHI102, CH Instruments, diameter = 2 mm). The Pt working
electrode was polished before experiment using alumina slurry (0.05 μm), rinsed with distilled water and
subjected to brief ultrasonication to remove any adhered alumina microparticles. The electrodes were then
dried in an oven at 75 °C overnight to remove any residual traces of water. The CV data was calibrated by
adding ferrocene in THF solution at the end of experiments. In all cases, there is no indication that
addition of ferrocene influences the electrochemical behaviour of products. All electrochemical
measurements were performed at ambient temperatures under an inert N2 atmosphere in THF containing
0.1 M [nBu4N][PF6] as the supporting electrolyte. Data were recorded with Autolab NOVA software
(v.1.8).
PhNHNC(C6F5)H
This compound was prepared using a modified literature procedure. 2
2,3,4,5,6-pentafluorobenzaldehyde (1.96 g, 10 mmol) and phenylhydrazine (1.08 g, 10 mmol) were stirred
at room temperature in ethanol (30 mL) for 3 hours. After the reaction 60 mL water was added to the
reaction mixture, and stirred for 1 hour. The light yellow solid that precipitated was collected and washed
with water and hexane. After drying under reduced pressure overnight 2.8 g light yellow solid of
PhNHNC(C6F5)H (0.96 mmol, 96%) was obtained. 1H NMR (C6D6): δ 7.18 (t, 2H, J= 8 Hz, Ph m-H),
7.04 (d, 2H, J= 8 Hz, Ph o-H), 6.84 (t, 1H, J= 8 Hz, Ph p-H), 6.75 (s, 1H, NH), 6.62 (s, 1H, NHNCH). 13C
NMR (C6D6): δ 144.8 (dm, J= 252 Hz, C6F5), 144.3 (Ph i-C), 140.3 (dtt, J= 252, 14, 5 Hz, C6F5 p-F),
138.2 (dm, J= 245 Hz, C6F5), 130.0 (Ph m-C), 123.6 (q, J= 3 Hz, NHNC), 121.9 (Ph p-C), 113.6(Ph o-C),
111.5 (td, J= 12, 4 Hz, C6F5 i-C). 19F NMR (C6D6): δ -144.1 (dd, 2F, J= 22, 8 Hz, C6F5 m-F), -157.0 (t,
1F, J= 21 Hz, C6F5 p-F), -163.6 (td, 2F, J= 21, 8 Hz, , C6F5 o-F) ppm. Anal. calcd for C13H7N2F5: C,
54.56; H, 2.47; N, 9.79. Found: C, 54.59; H, 2.44; N, 9.75.
2
PhNNC(C6F5)NNHMes
A flask was charged with PhNHNC(C6F5)H (1.72 g, 6 mmol), sodium hydroxide (2.00 g, 50 mmol), water
(100 mL) and acetone (160 mL) and the mixture cooled to 0 °C. At this temperature, [MesN2]+[BF4](1.40 g, 6 mmol) was added slowly with stirring. The reaction mixture was slowly warmed up to RT and
stirred for an additional 30 mins. Acetic acid was added to the reaction mixture until pH = 7. The reaction
mixture was stirred for another 2 hours. The crude organic product was extracted into CH2Cl2 and the
solution was concentrated. The product was purified by recrystallization from CH2Cl2/MeOH at -30 °C
for 2 days to give 1.2 g of PhNNC(C6F5)NNHMes (2.7 mmol, 45%). 1H NMR (400 MHz, CDCl3, 25 °C)
δ 12.21 (s, 1H, NH), 7.41- 7.35 (m, 4H, Ph o-H, Ph m-H), 7.31 (t, 1H, J= 6.6, Ph p-H), 6.95 (s, 2H, Mes
m-H), 2.41 (s, 6H, Mes o-CH3), 2.31 (s, 3H, Mes p-CH3). 19F NMR (376.4 MHz, C6D6, 25 °C) δ -139.3
(dd, 2F, J= 23.3, 7.5, C6F5 m-F), -154.5 (t, 1F, J= 20.9, C6F5 p-F), -162.9 (td, 2F, J= 23.0, 5.6, C6F5 oF).13C NMR (400 MHz, CDCl3, 25 °C) δ 145.5 (dm, J= 251.8, C6F5), 145.2 (Ph i-C), 144.8 (Mes i-C),
141.4 (dm, J= 259.0, C6F5), 140.0 (Mes p-C), 137.8 (dm, J= 249.6, C6F5), 135.8 (NNCNN), 132.8 (Mes
o-C), 130.8 (Ph m-C), 129.7 (Mes m-C), 125.3 (Ph p-C), 116.7(Ph o-C), 111.5-111.1 (m, C6F5), 21.4 (Mes
p-CH3), 20.6 (Mes o-CH3). Anal. calcd for C19H11N4F5: C, 61.11; H, 3.96; N, 12.96. Found: C, 61.23; H,
3.98; N, 12.80.
(PhNHNC(C6F5)NNMes)2Zn (1b)
A schlenk flask was charged with PhNNC(C6F5)NNHMes (258.7 mg, 0.60 mmol), 1.2M solution of
Me2Zn in toluene (0.25 mL, 0.60 mmol) and toluene 10 mL. The reaction mixture was stirred at RT
overnight after which all volatiles were removed under vacuo. The crude product was dissolved in 10 mL
of hexane and all volatiles was removed under vacuo again. After drying under vacuo, 210.5 mg deep
orange solid of (PhNHNC(C6F5)NNMes)2Zn (0.55 mmol, 76%) could be obtained. The isolated product is
about 95 % pure with some unidentified impurity and free ligand present. Because of good solubility in
all the common organic solvents, 1b is very hard to purify further and was used as such in subsequent
reactions. 1H NMR (400 MHz, C6D6, 25 °C) δ 7.75 (d, 2H, J = 7.9, Ph o-H), 7.21 (t, 2H, J = 7.9, Ph m-H),
6.92 (t, 1H, J = 7.6, Ph p-H), 6.33 (s, 2H, Mes m-H), 1.95 (s, 3H, Mes p-CH3), 1.82 (bs, 6H, Mes o-CH3).
19F NMR (376.4 MHz, C D , 25 °C) δ -143.67 (dd, 2F, J = 24.7, 7.9, C F m-F), -156.4 (t, 1F, J = 21.5,
6 6
6 5
C6F5 p-F), -163.0 (td, 2F, J = 21.7, 8.1, C6F5 o-F). 13C NMR (100.6 MHz, C6D6, 25 °C) δ 151.8 (Ph i-C),
148.0 (Mes i-C), 148.1-147.7 (m, C6F5), 145.7-145.3 (m, C6F5), 143.0-142.4 (m, C6F5), 140.4-139.9 (m,
C6F5), 139.9-139.3 (m, C6F5), 137.4 (Mes p-C), 133.7 (NNCNN), 130.4 (Ph o-C), 130.1 (bs, Mes o-C),
129.3 (Mes m-C), ~128.5 (overlapped, Ph p-C), 120.9 (Ph o-C), 115.8 (td, J = 17.3, 4.0, C6F5 i-C), 21.1
(Mes p-CH3), 18.5 (bs, Mes o-CH3). The NMR spectra are shown below. (Figure S4)
(PhNNC(p-tol)NNPh)BF2 (2a)
A schlenk flask was charged with 1a (610 mg, 0.83 mmol), BF3∙Et2O (0.4 mL, 3.24 mmol) and 10 mL of
toluene. The reaction mixture was stirred at 70°C overnight after which the color had changed from blue
to purple and all volatiles were removed under reduced pressure. To the residue was added 10 mL of
toluene and BF3∙Et2O (0.4 mL, 3.24 mmol), and the mixture was stirred at 70 °C overnight, upon which
the color had changed to red. The volatiles were removed in vacuo and the residue was taken up into
hexane and recrystallized by slowly cooling the clear red solution to -30 °C to afford 517 mg of
(PhNNC(p-tol)NNPh)BF2 (1.43 mmol, 86%) as red crystalline material. 1H NMR (400 MHz, C6D6, 25
°C) δ 8.06 (d, 2H, J = 8.2, p-tolyl CH), 7.91 (d, 4H, J = 8.4, Ph o-H), 7.09 (d, 2H, J = 8.2, p-tolyl CH),
3
7.01 (t, 4H, J = 7.1, Ph m-H), 6.95 (t, 2H, J = 7.2, Ph p-H), 2.13 (s, 3H, p-tolyl CH3). 19F NMR (376.4
MHz, C6D6, 25 °C) δ -144.4 (q, 2F, J = 28.8, BF2). 11B NMR (128.3 MHz, C6D6, 25 °C) δ -0.06 (t, 1B, J =
28.7, BF2). 13C NMR (100.6 MHz, C6D6, 25 °C) δ 150.3 (Ph i-C), 144.8 (NCN), 139.8 (p-tolyl i-C), 131.8
(p-tolyl CMe), 130.1 (Ph m-CH), 130.0 (p-tolyl CH), 129.6 (Ph p-CH), 126.4 (p-tolyl CH), 124.2 (Ph oCH), 21.6 (p-tolyl CH3). Anal. Calcd for C20H17BF2N4: C, 66.32; H, 4.73; N, 15.47. Found: C, 66.39; H,
4.75; N, 15.30. The NMR spectra are shown below. (Figure S5)
[(PhNNC(p-tol)NNPh)BF2][Cp2Co](THF) (3a)
A mixture of solid (PhNNC(p-tol)NNPh)BF2 (24.9 mg, 0.069 mmol) and Cp2Co (14.9 mg, 0.079 mmol)
was prepared. After addition of 2 mL THF, the color of the reaction mixture changed to green. Slow
diffusion of hexane (4 mL) into the THF solution precipitated 42 mg of [(PhNNC(ptol)NNPh)BF2][Cp2Co](THF) as green crystalline material (0.067 mmol, 98%). Anal. Calcd for
C34H35BCoF2N4O: C, 65.50; H, 5.66; N, 8.99. Found: C, 65.47; H, 5.71; N, 8.99.
(PhNNC(C6F5)NN(BF3)Mes)2Zn (4b)
A mixture of 1b (100.0 mg, 0.108 mmol), BF3∙Et2O (0.04 mL, 0.32 mmol) and 10 mL of toluene was
prepared. The reaction mixture was stirred at 70°C for 2 hours after which the color had changed to
orange. Slow diffusion of 5 mL of hexane into the toluene solution at -30 °C for 4 days resulted in
precipitation of 98 mg orange crystals of 4b (0.092 mmol, 85%). 1H NMR (400 MHz, C6D6, 25 °C) δ 7.76
(d, 2H, J = 8.1, Ph o-H), 7.01 (t, 2H, J = 7.7, Ph m-H), 6.89 (t, 1H, J = 7.4, Ph p-H), 6.35 (s, 1H, Mes mH), 6.14 (s, 1H, Mes m-H), 2.48 (s, 3H, Mes o-CH3), 2.29 (s, 3H, Mes o-CH3), 1.79 (s, 3H, Mes p-CH3),
11B NMR (128.3 MHz, C D , 25 °C) δ 0.78 (s, 1B, BF ). 19F NMR (376.4 MHz, C D , 25 °C) δ -130.3 (d,
6 6
3
6 6
1F, J = 23.9, C6F5 m-F), -136.7 (d, 1F, J = 23.9, C6F5 m-F), -148.4 (s, 3F, BF3), -152.7 (t, 1F, J = 21.8,
C6F5 p-F), -161.6 (td, 1F, J = 22.6, 7.3, C6F5 o-F), -163.0 (td, 1F, J = 22.7, 7.7, C6F5 o-F). 13C NMR
(100.6 MHz, C6D6, 25 °C) δ 148.6 (Ph i-C), 144.7 (dm, 1JCF ~ 253, C6F5 o-C), 142.1 (dm, 1JCF ~ 260, C6F5
p-C) 139.2 (Mes i-C), 137.2 (dm, 1JCF ~ 252, C6F5 m-C), 136.3 (Mes o-C), 136.0 (Mes o-C), 134.5 (Ph pC), 132.4 (Mes p-C), 130.5 (NNCNN), 129.7 (Ph m-C), 129.1 (Mes m-C), ~128.5 (overlapped, Mes m-C),
122.4 (Ph o-C), 108.9 (td, J = 19.4, 4.0, C6F5 i-C), 19.9 (Mes p-CH3), 17.9 (Mes o-CH3). Anal. Calcd for
C44H32B2F16N8Zn: C, 49.68; H, 3.03; N, 10.53. Found: C, 50.18; H, 3.15; N, 10.18. The NMR spectra are
shown below. (Figure S6)
(PhNNC(C6F5)NNMes)BF2 (2b)
A solution of (PhNNC(C6F5)NN(BF3)Mes)2Zn (4b) (103.1 mg, 0.097 mmol) in toluene (10 mL) was
stirred at 130°C for 12 hours after which all volatiles were removed under vacuo. The crude product was
dissolved in hexane and separated from solid by filtration. The product was further purified by silica
column chromatography with CH2Cl2/hexane (1:10)(r = 0.2). The fractions were collected and removing
solvent in vacuo afforded the product as red solid (51 mg, 0.104 mmol, 54%). 1H NMR (400 MHz,
CDCl3, 25 °C) δ 7.85-7.78 (m, 2H, Ph o-H), 7.52-7.43 (m, 3H, Ph m-H and p-H), 6.90 (s, 2H, Mes m-H),
2.27 (s, 3H, Mes p-CH3), 2.05 (s, 6H, Mes o-CH3). 11B NMR (128.3 MHz, CDCl3, 25 °C) δ -1.34 (t, 1B, J
= 23.8, BF2). 19F NMR (376.4 MHz, CDCl3, 25 °C) δ -140.9 - -141.1 (m, 2F, C6F5 m-F), -151.8 (tt, 1F, J
= 21.0, 2.2, C6F5 p-F), -153.2 (q, 2F, J = 23.7, BF2), -161.2 - -161.4 (m, 2F, C6F5 o-F). 13C NMR (100.6
MHz, CDCl3, 25 °C) δ 147.2-146.7 (m, C6F5), 144.7-144.2 (m, C6F5), 143.8-143.2 (m, C6F5), 142.8 (Ph, iC), 141.1-140.7 (m, C6F5), 140.7-140.4 (m, C6F5), 139.7 (NNCNN), 139.3 (Mes i-C). 139.5-139.1 (m,
4
C6F5), 137.1-136.6 (m, C6F5), 134.4 (Mes o-C), 130.7 (Ph p-C), 129.6 (Mes m-C and Ph m-C), 123.9 (Ph
o-C), 109.8 (td, J = 15.6, 4.1, C6F5 i-C), 21.3 (Mes p-CH3), 17.8 (Mes o-CH3). Anal. Calcd for
C19H10BF7N4: C, 55.03; H, 3.36; N, 11.67. Found: C, 55.20; H, 3.53; N, 11.26. The NMR spectra are
shown below. (Figure S7)
5
X-ray crystallography
Suitable crystals of 2a, 3a, and 4b were mounted on a cryo-loop in a drybox and transferred, using inertatmosphere handling techniques, into the cold nitrogen stream of a Bruker D8 Venture diffractometer.
The final unit cell was obtained from the xyz centroids of 9981 (2a), 9687 (3a) and 9950 (4b) reflections
after integration. Intensity data were corrected for Lorentz and polarisation effects, scale variation, for
decay and absorption: a multiscan absorption correction was applied, based on the intensities of
symmetry-related reflections measured at different angular settings (SADABS).5 The structures were
solved by direct methods using the program SHELXS.6 The hydrogen atoms were generated by
geometrical considerations and constrained to idealised geometries and allowed to ride on their carrier
atoms with an isotropic displacement parameter related to the equivalent displacement parameter of their
carrier atoms. Structure refinement was performed with the program package SHELXL.6 Crystal data and
details on data collection and refinement are presented in Table S1.
For compound 3a, refinement was frustrated by disorder problems. From the solution it was clear that the
THF solvate molecule was partly occupied (81%) and disordered: the electron density of the atoms
appeared to be spread out. The THF C atom that showed the most unrealistic displacement parameters
was described by two site occupancy factors with separately refined displacement parameters. The s.o.f.
of the major/minor fractions refined to 0.52/0.29, respectively. The remaining atoms of the THF solvate
molecule also showed large displacement parameters, but attempts to model this with a two-site
occupancy model did not lead to significant improvements. In addition, one of the cyclopentadienyl rings
of the Cp2Co+ fragment suffered from rotational disorder. A two-site occupancy model was applied: both
s.o.f. for the major fraction refined to 0.54.
For compound 4b, refinement was frustrated by disorder problems. The two independent molecules in the
asymmetric unit both showed a different kind of disorder. For one of them, it was clear from the solution
that a phenyl ring was disordered over two positions. A difference Fourier synthesis allowed the location
of the minor orientation, and a two-site occupancy model was applied. The s.o.f. of both refined to a value
of 0.50. One of the BF3 units in this molecule showed large displacement parameters, but this could not
be satisfactorily modelled by a disorder model. The second independent molecule also showed unrealistic
displacement parameters for a BF3 fragment: for two of the F atoms in this group, a two-site occupancy
model was applied, the major fraction of which refined to a s.o.f. of 0.61.
6
Table S1. Crystallographic data for 2a, 3a and 4b
chem formula
Mr
cryst syst
color, habit
size (mm)
space group
a (Å)
b (Å)
c (Å)
α (°)
β (°)
γ (°)
V (Å3)
Z
calc, g.cm-3
µ(Mo Kα), mm-1
F(000)
temp (K)
 range (°)
data collected (h,k,l)
min, max transm
rflns collected
indpndt reflns
observed reflns Fo 
2.0 σ (Fo)
R(F) (%)
wR(F2) (%)
GooF
weighting a,b
params refined
min, max resid dens
2a
C20H17BF2N4
362.19
monoclinic
red, needle
0.34 x 0.24 x 0.05
P21/c
10.4160(6)
18.8213(11)
9.2633(5)
3a
C33.25H33BCoF2N4O
612.88
monoclinic
green, platelet
0.30 x 0.18 x 0.06
P21/n
12.2031(7)
17.4363(9)
14.4788(7)
4b
C44H32B2F16N8Zn
1063.76
monoclinic
orange, platelet
0.20 x 0.16 x 0.03
P21/c
28.1225(14)
20.6482(10)
15.3728(7)
101.539(2)
97.446(2)
93.868(2)
1779.30(17)
4
1.352
0.096
752
100(2)
5.80–55.82
-13:13, -24:24, -11:12
0.9680, 0.9952
49978
4282
3564
3054.8(3)
4
1.333
0.607
1276
200(2)
5.675-53.32
-15:15, -22:22, -18:17
0.8389, 0.9645
105601
6775
5657
8906.3(7)
8
1.587
0.663
4288
100(2)
5.878-52.737
-36:36, -26:26, -20:19
0.6950, 0.7456
285779
20514
15776
3.74
8.92
1.037
0.0416, 0.7967
245
-0.219, 0.379
4.37
12.67
1.070
0.0770, 1.6064
455
-0.512, 0.960
5.26
11.07
1.083
0.0422, 16.6302
1353
-0.914, 2.757
7
Figure S1. Molecular structure of 2a showing 50% probability ellipsoid. The hydrogen atoms are omitted
for clarity
8
EPR spectrum of 3a
Figure S2. EPR of 3a (frozen THF solution at 20K)
500000
400000
300000
200000
100000
0
3240 3260 3280 3300 3320 3340 3360 3380 3400 3420 3440
-100000
-200000
-300000
-400000
-500000
9
UV-VIS data
Figure S2a. UV-Vis of 2a, 2b and 3a in THF.
UV-Vis in THF
Extinction coefficient
30000
25000
20000
2a
3a
2b
15000
10000
5000
0
300
400
500
600
nm
700
800
900
Figure S2b. UV-Vis of 1b and 4b in 1,2-dichloroethane.
10
Extinction coefficient
UV-Vis in DCE
40000
35000
30000
25000
20000
1b
4b
15000
10000
5000
0
300
400
600 nm
500
700
800
900
NMR spectra for compounds 1b, 2a, 4b and 2b.
1300
2.06
2.03
1.95
1.82
2.30
2.73
6.33
6.94
6.92
7.19
7.16
7.76
7.76
7.74
7.74
7.21
Figure S4. (a) 1H-NMR of 1b in C6D6
1200
1100
1000
900
800
700
600
500
400
300
200
100
12.0
11.5
11.0
10.5
10.0
9.5
9.0
8.5
8.0
7.5
7.0
6.5
6.0
f1 (ppm)
2.80
5.84
2.00
1.12
2.03
1.86
0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
-100
1.5
1.0
0.5
0.0
Figure S4.(b) 19F-NMR of 1b in C6D6
11
-162.94
-162.96
-163.00
-163.01
-163.06
-163.08
-163.10
-156.31
-156.37
-156.43
-143.63
-143.65
-143.70
-143.72
6500
6000
5500
5000
4500
4000
3500
3000
2500
2000
1500
1000
500
-130
-135
-140
-145
-150
f1 (ppm)
2.20
0.98
2.00
0
-155
-500
-160
-165
8.4
8.2
8.0
7.8
7.6
7.4
7.2
7.0
2.13
3.27
7.10
7.08
7.03
7.01
6.99
6.96
6.95
6.93
2.13
4.12
2.03
7.92
7.90
4.02
2.00
8.07
8.05
Figure S5. (a) 1H-NMR of 2a in C6D6
6.8
6.6
6.4
6.2
6.0
5.8
5.6
5.4
5.2
5.0
f1 (ppm)
4.8
4.6
4.4
4.2
4.0
3.8
3.6
3.4
3.2
3.0
2.8
2.6
2.4
2.2
2.0
Figure S5. (b) 19F-NMR of 2a in C6D6
12
-141.8
-142.0
-142.2
-142.4
-142.6
-142.8
-143.0
-143.2
-143.4
-143.6
-144.00
-143.93
-143.85
-143.77
-141.6
-143.8
-144.0
f1 (ppm)
-144.2
-144.4
-144.6
-144.8
-145.0
-145.2
-145.4
-145.6
-145.8
-146.0
-146.2
0.16
-0.06
-0.29
Figure S5. (c) 11B-NMR of 2a in C6D6
9
8
7
6
5
4
3
2
1
0
-1
f1 (ppm)
-2
-3
-4
-5
-6
-7
-8
-9
-10
13
135
130
125
21.64
140
124.18
145
128.63
128.15
126.36
139.76
150
131.84
144.80
155
150.34
Figure S5. (d) 13C-NMR of 2a in C6D6
120
115
110
105
100
95
90
85
f1 (ppm)
80
75
70
65
60
55
50
45
40
35
30
25
20
Figure S6. (a) 1H-NMR of 4b in C6D6
14
-129
-132
-135
-138
-141
-144
-147
-150
4.0
3.5
-153
3.0
-156
-159
-163.00
-163.02
-163.06
-163.08
4.5
2.5
1.01
5.0
f1 (ppm)
1.00
5.5
-161.52
-161.54
-161.58
-161.60
-161.64
-161.66
6.0
-152.60
-152.66
-152.72
6.5
0.99
7.0
-148.38
-148.43
-136.69
-136.75
-130.27
-130.33
7.5
3.14
0.98
1.00
8.0
2.0
3.06
3.19
3.06
1.00
0.99
1.04
2.13
2.00
1.79
2.29
2.48
6.14
6.35
7.01
6.99
6.91
6.89
6.88
7.16
7.76
7.74
4000
3500
3000
2500
2000
1500
1000
500
0
1.5
Figure S6. (b) 19F-NMR of 4b in C6D6
-162
Figure S6. (c) 11B-NMR of 4b in C6D6
15
0.78
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
-1
-2
f1 (ppm)
-3
-4
-5
-6
-7
-8
-9
-10
-11
-12
-13
-14
-15
-16
-17
20.15
19.94
17.92
17.86
109.10
109.05
108.90
108.86
108.71
108.67
122.69
122.42
127.87
127.39
125.26
139.24
137.99
136.04
134.46
132.37
145.61
143.14
148.67
Figure S6. (d) 13C-NMR of 4b in C6D6 (inset highlighting resonances due to C6F5 group)
6000
5500
5000
4500
4000
3500
3000
2500
2000
1500
1000
500
0
-500
150
145
140
135
130
125
120
115
110
105
100
95
90
85
80
f1 (ppm)
75
70
65
60
55
50
45
40
35
30
25
20
15
16
2.07
2.29
6.92
7.26
7.49
7.49
7.48
7.47
7.85
7.83
Figure S7. (a) 1H-NMR of 2b in CDCl3
7000
6500
6000
5500
5000
4500
4000
3500
3000
2500
2000
1500
1000
500
8.0
7.8
7.6
7.4
7.2
7.0
6.8
6.6
6.4
6.2
6.0
5.8
5.6
5.4
5.2
5.0
4.8
f1 (ppm)
4.6
4.4
4.2
4.0
3.8
3.6
3.4
3.2
3.0
2.8
2.6
2.4
6.14
3.12
1.98
3.03
2.00
0
2.2
-500
2.0
1.8
17
-161.19
-161.20
-161.22
-161.25
-161.27
-161.31
-161.33
-161.34
-153.05
-153.12
-153.18
-153.24
-151.72
-151.77
-151.78
-151.78
-151.83
-151.83
-140.94
-140.96
-140.97
-141.00
-141.00
-141.02
Figure S7. (b) 19F-NMR of 2b in CDCl3
1700
1600
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
-132
-134
-136
-138
-140
-142
-144
-146
-148
-150
f1 (ppm)
-152
-100
1.98
2.12
0.98
2.00
0
-154
-156
-158
-160
-162
-164
-166
-1.15
-1.34
-1.53
Figure S7. (c) 11B-NMR of 2b in CDCl3
110
100
90
80
70
60
50
40
30
20
10
0
-10
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
f1 (ppm)
-1
-2
-3
-4
-5
-6
-7
-8
-9
-10
-11
-12
-13
-14
-15
18
17.58
21.02
77.31
77.19
76.99
76.67
109.72
109.68
109.56
109.52
109.41
109.37
123.70
123.70
130.43
129.34
134.20
136.57
139.10
142.61
146.83
146.78
Figure S7. (d) 13C-NMR of 2b in CDCl3
3200
3000
2800
2600
2400
2200
2000
1800
1600
1400
1200
1000
800
600
400
200
0
-200
150
140
130
120
110
100
90
80
f1 (ppm)
70
60
50
40
30
20
10
19
References
1. (a) M. P. Doyle, W. J. Bryker, J. Org. Chem. 1979, 44, 1572. (b) M.-C. Chang, T. Dann, D. P. Day, M.
Lutz, G. G. Wildgoose, and E. Otten, Angew. Chem. Int. Ed., 2014, 53, 4118.
2. N. I. Petrenko and T. N. Gerasimova, J. Fluorine Chem. 1990, 19, 359.
20