Visible-Light-Induced Trifluoromethylation of Unactivated Alkenes with Tri(9-anthryl)borane as an Organophotocatalyst

Article abstract of DOI:10.1021/acs.joc.9b01624

Tri(9-anthryl)borane was successfully applied as an organophotocatalyst for the visible-light-induced trifluoromethylation of unactivated alkenes with CF₃I. The mild reaction conditions tolerated a variety of functional groups, and the reaction could be extended to perfluoroalkylations with C₃F₇I and C₄F₉I. Mechanistic studies revealed that the photoredox catalysis involves an oxidative quenching pathway.

Full text of DOI:10.1021/acs.joc.9b01624

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Article
Visible-Light-Induced Trifluoromethylation of Unactivated
Alkenes with Tri(9-anthryl)borane as an Organophotocatalyst
Jisu Moon, Yu Kyung Moon, Do Dam Park, Sukyung Choi, Youngmin You, and Eun Jin Cho
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.9b01624 • Publication Date (Web): 07 Aug 2019
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The Journal of Organic Chemistry
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Visible-Light-Induced Trifluoromethylation of Unactivated Alkenes
with Tri(9-anthryl)borane as an Organophotocatalyst
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Jisu Moon,† Yu Kyung Moon,‡ Do Dam Park,† Sukyung Choi,‡ Youngmin You,*,‡ and Eun Jin Cho*,†
†Department of Chemistry, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea
‡Division of Chemical Engineering and Materials Science, Ewha Womans University, Seoul 03760, Republic of Korea
ABSTRACT: Tri(9-anthryl)borane was successfully applied as an organophotocatalyst for the visible-light-induced
trifluoromethylation of unactivated alkenes with CF3I. The mild reaction conditions tolerated a variety of functional groups, and the
reaction could be extended to perfluoroalkylations with C3F7I and C4F9I. Mechanistic studies revealed that the photoredox catalysis
involves an oxidative quenching pathway.
Introduction
trifluoromethylation reactions in the presence of an
organophotocatalyst remain less developed, with only a few
reported examples. Herein, we successfully exploited tri(9-
anthryl)borane (1) as an organophotocatalyst in the
trifluoromethylation of unactivated alkenes with CF3I
(Scheme 1b).
In the past decades, extensive research efforts have been
devoted towards the introduction of fluoroalkyl moieties into
target molecules.1 In general, fluoroalkylated compounds are
characterized
by
improved
metabolic
stability,
bioavailability, lipophilicity, and binding selectivity as
compared to their non-fluoroalkylated counterparts.2 Among
the various fluoroalkyl groups available, the trifluoromethyl
group is the most prevalent in pharmaceuticals and
agrochemicals.3 For this reason, various trifluoromethylation
methods have been developed, including visible-light-
induced reactions, which have recently attracted considerable
attention due to their environmental compatibility and
Scheme 1. (a) Examples of visible-light photocatalysts used in trifluoromethylation
reactions. (b) Left, UVvis absorption spectrum of 10 M tri(9-anthryl)borane (Ar-
saturated CH3CN). Right, fluorescence (solid line) and photoluminescence excitation
(dotted line) spectra of 10 M tri(9-anthryl)borane (Ar-saturated CH3CN). ex = 470
nm and em = 545 nm.
mechanistic
versatility.3,4
Visible-light-induced
trifluoromethylation reactions typically involve the use of
polypyridyl-based Ru, Ir and Pt complexes as
photosensitizers.3 Scheme 1 shows the widely used Ru- and
Ir-complexes
in
trifluoromethylations,
including
[Ru(bpy)3]Cl2, [Ru(phen)3]Cl2, [Ir(dtbbpy)(ppy)2]PF6, and
fac-Ir(ppy)3. Metal complexes containing Pt and Cu have
also been explored as photocatalysts (Scheme 1a-i). Despite
synthetic utility, transition-metal photocatalysts have several
disadvantages. Some metal complexes are expensive and
present toxicity issues associated with metal residues when
used in the synthesis of pharmaceuticals. To circumvent
these problems, several organic dyes such as Eosin Y,
methylene blue, and Nile red (Scheme 1a-ii) have been
examined
in
trifluoromethylations.5
However,
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was more negative than the reduction potential of CF3I
Page 2 of 9
(a) previous work
R
1
2
3
4
5
6
7
8
photocatalysis
R
(0.91 V vs. SCE), suggesting thermodynamic allowance for
photoinduced electron transfer from 1 to CF3I (Figure 1 and
Figure S1 in ESI). On the contrary, reductive quenching of
the excited-state 1 by DBU, a sacrificial electron donor, was
found to be thermodynamically improbable because the
excited-state reduction potential (0.73 V vs. SCE) of 1 was
less positive than Eox (1.22 V vs. SCE) of DBU.
CF3 reagents
+
CF3
i) Transition-metal photocatalyst
2+
2+
N
Ru
N
N
Ru
N
N
N
N
N
N
N
N
N
N
Ir
N
N
9
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[Ru(bpy)3]2+
[Ru(phen)3]2+
fac-Ir(ppy)3
_1.12 V
+
(
)
+
_0.91 V
PMP
PMP
N
*
CF3I
N
N
N
N
N
N
Ir
N
Cu
Pt
B
O
O
N
PMP
1
PMP
[Ir(dtbbpy)(ppy)2]+
ii) Organophotocatalyst
[Cu(dap)2]+
Pt(ppy)acac
( + )
x
0.73 V
N
N
1.22 V
Figure 1. Schematic representations of the electron transfer of the excited-state
CO2
Br
N
O
1 with DBU or CF3I.
N
Br
Br
O
Et2N
O
N
S
N
O
O
Cl
Br
Methylene Blue
Eosin Y
Nile Red
(b) this work
cat. tri(9-anthryl)borane
R
R
CF3I
+
CF3
20
1.2
UV
PL
PLE
469 nm
545 nm
1.0
0.8
0.6
0.4
0.2
0.0
15
10
5
B
470 nm
0
200
300
400
500
600
700
300
400
500
600
700
800
Wavelength (nm)
Wavelength (nm)
Result and Discussion
Figure 2. Fluorescence decay traces of 100 M 1 (Ar-saturated CH3CN)
recorded at an emission wavelength of 545 nm after picosecond pulsed laser
excitation at 377 nm (temporal resolution = 0.025 ns) in the presence of (a)
increased concentrations of CF3I (0160 mM) and (b) 1.0 mM DBU. The inset
graph in (a) is a pseudo-first-order plot. The experiments were performed in
triplicate using fresh samples. The average and standard deviations were
obtained from the three experiments.
Tri(9-anthryl)borane 1 was developed by the Yamaguchi
group for potential applications in organic light-emitting
devices (OLEDs).6,7 However, 1 has not been utilized in
synthetic chemistry, although it fulfils the requirements for a
visible-light photocatalyst. The strong visible-light
absorption ability of this compound was demonstrated by its
UV-vis absorption spectrum which contained an
intramolecular charge transfer (ICT) transition from the 
orbital of the anthryl group to the p orbital of borane at 470
nm ( = 15000 M1 cm1) (Scheme 1b). The large  value of
1 is a contrasting advantage over conventional late-
transition-metal complexes, which typically display  < 104
M1 cm1 in the metal-to-ligand charge-transfer transition
bands in the visible region. The excited-state oxidation
potential (E*ox, 1.12 V vs. SCE; E*ox = Eox  E(S1), Eox
(1.16 V vs SCE) and E(S1) (2.28 eV) are the ground-state
oxidation potential and the singlet excited-state energy,
respectively; see ESI, Figure S1 for the voltammogram of 1)
Stern–Volmer experiments were performed to examine the
excited-state electron transfer from 1 to CF3I. Fluorescence
decay traces of 100 M 1 were recorded at a wavelength of
545 nm employing time-correlated single-photon-counting
techniques, with increasing the concentration of CF3I. As
shown in Figure 2a, the fluorescence lifetime of 100 M 1
was 1.2 ns in a deaerated CH3CN solution. The fluorescence
lifetime decreased in proportion with the added concentration
of CF3I. On the contrary, the fluorescence lifetime did not
decrease in the presence of DBU (Figure 2b). A delayed
fluorescence component was rather observed, which was
likely due to suppression of non-radiative processes by
hydrophobic interactions between
1 and DBU. The
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invariance of the lifetime of the prompt fluorescence
We commenced our investigation using 1-dodecene 2a as the
model substrate and CF3I in the presence of 0.5 mol% 1 as
the organophotocatalyst (Table 1). 480 nm LEDs were used
1
2
3
4
5
6
7
8
indicated the absence of reductive quenching of 1 by DBU.
A pseudo-first-order plot was constructed with employing
the quenching rate of CF3I which was computed using the
relationship, quenching rate = 1/  1/0, where  and 0 are
the fluorescence lifetime of 1 in the absence and presence of
CF3I, respectively (the inset graph in Figure 2a). A linear fit
of the data returned a rate constant for oxidative quenching
of 1 by CF3I to be as large as 9.4108 M1 s1. The transient
fluorescence studies revealed fast electron transfer from the
excited-state 1 to CF3I.
to maximize the visible-light absorption ability of 1 (ex
=
470 nm). Moreover, to obtain the alkenyl-CF3 compound 3a
as the final product, amine bases were used as additives
because an amine in the reaction medium can play multiple
roles: a sacrificial electron donor in photoredox catalysis, an
elimination base for the dehydrohalogenation of the
intermediate, and a Brønsted base for deprotonation.3d,8
Indeed, the use of amine additives provided the desired 3a
with E-selectivity (entries 1-3).3,9-11 DBU was an optimal
additive to give 3a in 95% yield, while reactions with TEA
or TMEDA gave lower yields of 3a along with a
trifluoromethylated iodide product (see C in Scheme 2).12 On
the other hand, the reaction in the absence of an amine or the
presence of an inorganic base such as K2CO3 and Cs2CO3 did
not provide 3a (entries 46). Additional 1H NMR
experiments showed that there was no Lewis acid-base
interaction between 1 and amines, indicating 1 cannot
function as a Lewis acid (Figure S2 in ESI). Reactions in the
presence of widely used metal- or organo-photocatalysts
such as fac-Ir(ppy)3, Ru(phen)3Cl2, or Eosin Y provided 3a
in lower yields (entries 3 vs 7-9), probably due to the less
efficiency in electron transfer process than 1 under 480 nm-
light irradiation.13
Control experiments showed that the reaction requires both
visible-light irradiation and a photocatalyst (entries 10 and
11). CH3CN was the best solvent system for the
transformation (entries 3, 1216). Further screening of the
reaction concentration and stoichiometry of the reagents
confirmed that the best reaction conditions that provided 3a
in 95% yield were as follows: 0.5 mol% of 1, 23 equiv of
CF3I, and 2 equiv of DBU in CH3CN (0.10.2 M) (entry 3).
The use of CFL or green LEDs as the visible-light source
instead of the 480 nm LEDs decreased the reaction efficiency,
showing the dependence of the transformation on irradiation
wavelength (entries 17 and 18). Notably, the reaction
proceeded in the absence of 1, despite the lower reactivity
through halogen bond complex formation between DBU and
CF3I, where visible-light-induced single-electron transfer
from DBU to CF3I generated the ·CF3 radical (entry 19).5c, 14
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Table 1. Optimization of trifluoromethylation of alkene 2aa
1
tri(9-anthryl)borane ( , 0.5 mol%)
base (2 equiv.)
CF3I
+
CF3
7
7
solvent (0.2 M), rt, 3 h
480 nm LEDs (18 W, 23 mW/cm2)
(3 equiv.)
2a
3a
entry
1
base
TEA
solvent
variation
yieldb
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
THF
-
12 (52)c
2
TMEDA
DBU
-
-
43 (16)c
3
-
95
4
-
-
-
5
K2CO3
Cs2CO3
DBU
DBU
DBU
DBU
DBU
DBU
DBU
DBU
DBU
DBU
DBU
-
6
-
-
7
fac-Ir(ppy)3
91
8
Ru(phen)3Cl2
80 (2)c
77 (3)c
5
9
Eosin Y
10
11
12
13
14
15
16
17
no hv
no 1
0
-
62
DCM
-
68
DMF
-
44
1,4-dioxane
Et2O
-
80
Scheme 2. Proposed mechanism of the alkenyl trifluoromethylation
-
67
CH3CN
CFL (20 W)
82
520 nm green LEDs
(18 W, 10 mW/cm2)
18
19
DBU
DBU
CH3CN
CH3CN
8 (56)d
no 1, CFL (20 W)
31 (58)d
aReaction scale: 2a (0.1 mmol); bThe yield was determined by 19F NMR
c
spectroscopy with trifluorotoluene as an internal standard. Numbers in parentheses
indicate yields of the trifluoroalkenyl iodide. dNumbers in parentheses indicate yields
after 24 h.
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O
1
2
3
4
5
6
7
8
NR'3
n
1
I
+
CF3
5
3e
86%
N
CF3
HI
R
H
NHR'3
3
NR'3
or
Cl
eliminatio
1*
B
NR'3
I
B
NHR'3
O
6
7
3f
88%
94%
CF3I
1+
A
deprotonation
N
CF3
CF3
CF3
H
R
I
I
NR'3
C
CF3
O
3g
N
H
9
CF3
CF3
4
R
R
R
10
11
12
13
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19
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photocatalytic
oxidation
2
A
B
HO
8
9
3h
3i
77%
72%
CF3
CF3
O
HO
Based on the aforementioned results, we propose a plausible
mechanism for the trifluoromethylation of alkenes (Scheme
2). Initially, 1 is activated by visible light through the
O
CF3
10
11
3j
95%
90%
N
anthryl-to-borane
charge
transfer
transition.
The
photoactivated 1* is oxidatively quenched by one-electron
transfer to CF3I, producing [1]+ and the key intermediate,
·CF3 radical. Addition of the ·CF3 radical to alkene 2
generates trifluoromethylated radical species A. Atom-
transfer radical addition between A and CF3I can produce
iodo-trifluoromethylated product C, which after elimination
of HI in the presence of DBU, is converted into 3. Note that
this step also yields the ·CF3 radical. The radical propagation
is beneficial for increased photon economy. A photochemical
quantum yield determined using the standard ferrioxialate
actinometry was as high as 240% for the trifluoromethylation
of 2a (see ESI for the details). The quantum yield exceeding
100% is a strong indication for the presence of the radical
propagation step. Alternatively, 3 can be generated from
intermediate B, formed by the photocatalytic oxidation of A,
through DBU-promoted deprotonation. In the photocatalytic
cycle, reductive one-electron transfer from DBU or A to [1]+
regenerates 1.
3k
Si O
CF3
Me
O
12
13
3l
96%
90%
S
O
CF3
O
3m
CF3 (1.6 : 1)
aReaction scale: 2 (0.5 mmol); bisolated yield.
Next, we investigated the substrate scope of this
transformation by using a variety of terminal alkenes (Table
2). The mild reaction conditions facilitated the
trifluoromethylation of alkenes bearing diverse functional
groups, including ester (3c), aryl halides such as aryl
bromide (3d) and aryl chloride (3e), amide (3d, 3e, 3f, 3g),
unprotected alcohol (3h, 3i), lactam(3j), silyl ether (3k), and
sulfonates (3l). An internal alkene, (E)-dec-5-ene, also
underwent the transformation smoothly to give the
corresponding trifluoromethylated product 3m, despite the
formation of an E/Z mixture. Unfortunately, aromatic
alkenes15 were not suitable substrates for the transformation,
showing very low conversion under the conditions.
Table 2. Substrate scope of alkenesa
1
tri(9-anthryl)borane ( , 0.5 mol%)
DBU (2 equiv.)
R
R
CF3I
+
CF3
CH3CN (0.2 M), rt, 2-8 h
480 nm LEDs (18 W, 23 mW/cm2)
(3 equiv.)
2
3
entry
1
product
yield (%)b
93%
The reaction conditions were amenable to a large-scale
reaction: 3a could be prepared on a 10-mmol scale in a yield
similar to that of a 0.5-mmol scale reaction (Scheme 3).
3a
3b
CF3
7
CF3
2
3
88%
88%
Scheme 3. Gram-scale reaction of 2a
1
tri(9-anthryl)borane ( , 0.5 mol%)
DBU (2 equiv.)
CF3I
CF3
+
7
7
CH3CN (0.2 M), rt, 5 h
480 nm LEDs (18 W, 23 mW/cm2)
O
3c
(3 equiv.)
2a
3a
(1.53 g, 90%)
CF3
3
(1.70 g, 10 mmol)
O
O
Table 3. Perfluoroalkylations of alkenesa
4
3d
90%
N
CF3
H
Br
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were tolerated under the mild reaction conditions, and the
reaction could be extended to perfluoroalkylations with C3F7I
and C4F9I. N-Heterocycles were also suitable substrates for
the transformation. Our mechanistic studies revealed that the
photoredox catalysis involves an oxidative quenching
pathway. We believe that the photoreactivity of tri(9-
anthryl)borane would pave the way for widespread
applications in other useful transformations and set a new
1
tri(9-anthryl)borane ( , 0.5 mol%)
DBU (2 equiv.)
C3F7I
or
C4F9I
1
2
3
4
5
6
7
8
R
R
+
RF
MeCN (0.2 M), rt, 6 h
480 nm LEDs (18 W, 23 mW/cm2)
4
5
(RF = -C3F7)
(RF = -C4F9)
2
(2 equiv.)
entry
product
yield (%)b
90%
1
2
4a
5a
C3F7
stage
for
the
development
of
borane-based
7
9
organophotocatalysts.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
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60
C4F9
94%
7
Experimental Section
O
3
4c
93%
General Information. Anhydrous CH3CN was purchased from
Sigma-Aldrich chemical company in Sure-Seal bottle.
C3F7
3
a
O
Commercially available reagents were purchased from Sigma-
Aldrich, Alfa Aesar, Acros Organics, or TCI companies. Flash
column chromatography was performed using Merck silica gel 60
(70-230 mesh). EvoluChem LED 18 W [blue (480 nm, 23
mW/cm2)] was used as light sources. The fluoroalkylated alkene
O
4
5
6
5c
4j
5j
90%
92%
93%
C4F9
3
O
products were characterized by H, 13C{1H}, and 19F NMR, and
1
O
C3F7
FT-IR spectroscopy. NMR spectra were recorded on a Varian 600
N
MHz instrument (600 MHz for 1H NMR, 151 MHz for 13C NMR,
and 564 MHz for 19F NMR). Copies of H NMR, 13C{1H} NMR
1
and 19F NMR spectra can be found in the Supporting Information.
1H NMR experiments are reported in units, parts per million
(ppm), and were measured relative to residual chloroform (7.26
ppm) in the deuterated solvent. 13C NMR spectra are reported in
ppm relative to deuterochloroform (77.23 ppm), and all were
O
C4F9
N
aReaction scale: 2 (0.5 mmol); bisolated yield.
1
obtained with H decoupling. 19F NMR spectra are reported in
To further demonstrate the diversity and potential application
of the reaction, we attempted to carry out fluoroalkylations
using perfluoroalkyl iodides, including heptafluoropropyl
iodide (C3F7I) and nonafluorobutyl iodide (C4F9I) (Table 3).
Under the given conditions, the reactions proceeded
smoothly to give the corresponding perfluoroalkylated
alkenes 4 and 5 in excellent yields.
ppm, and all were taken composite pulse decoupling (CPD) mode.
Coupling constants were reported in Hz. FT-IR spectra were
recorded on a Tensor 27 Bruker FT-IR spectrometer. Reactions
were monitored by GC-MS using the Agilent GC 7890B/5977A
inert MSD with Triple-Axis Detector. Mass spectral data of all
unknown compounds were obtained from the Korea Basic
Science Institute (Daegu) on a Jeol JMS 700 high resolution mass
spectrometer.
Experimental Details
Scheme 4. Reaction of N-heterocyclesa: aReaction scale: 6 (0.5 mmol); bThe yield
was determined by 19F NMR spectroscopy with trifluorotoluene as an internal
standard due to the volatility of 7a.
1. Synthesis of tri(9-anthryl)borane (1).
Tri(9-anthryl)borane was synthesized by following the reported
procedure.6a A solution of 9-anthryllithium, prepared from 9-
bromoanthracene (5.14 g, 20 mmol) and n-BuLi (1.6 M hexane
solution, 13 mL, 21 mmol) in ether (30 mL), was added to an
1
tri(9-anthryl)borane( , 0.5 mol%)
Me
N
Me
N
TMEDA (2 equiv.)
CF3I
+
+
CF3
CH3CN (0.2 M), rt, 6 h
480 nm LEDs (18 W, 23 mW/cm2)
(3 equiv.)
.
b
ether (10 mL) solution of BF3 OEt2 (852 mg, 6 mmol) at 0 oC. The
7a
(95%)
6a
reaction mixture was stirred at room temperature for 12 h. The
orange precipitates produced were collected by filtration and then
washed with Et2O (5 mL x 2). Benzene was added to the
precipitates and the resulting suspension was stirred and then
filtered to remove insoluble salts. The filtrate was concentrated
under reduced pressure, followed by recrystallization from
benzene to afford of compound in 52% yield as orange crystals.
H
H
N
N
above conditions
CF3
CF3I
(3 equiv.)
Me
Me
7b
(85%)
6b
N-Heterocycles such as pyrrole and indole were also suitable
substrates for the trifluoromethylation. N-methylpyrrole 6a
and 3-Methylindole 6b were converted to the corresponding
CF3 compounds, 7a and 7b, respectively (Scheme 4). In the
transformation, the use of TMEDA as a base improved the
efficiency of the process.
In conclusion, we have employed tri(9-anthryl)borane as an
organophotocatalyst in the trifluoromethylation reactions of
unactivated alkenes. A wide variety of functional groups
2. Synthesis of trifluoromethylated alkenes (3a-3m).
A flame-dried tube equipped with a magnetic stirring bar was
charged with argon. The substrate (2: 0.5 mmol), tri(9-
anthryl)borane (0.5 mol%: 2.7 mg), DBU (1.0 mmol, 152.5 uL),
and CH3CN (2.5 mL, 0.2 M) were added to the tube. CF3I (1.5
mmol, 37.5 mL) was then delivered into the reaction mixture
using a gastight syringe. The mixture was stirred at room
temperature and irradiated in a distance of 15 cm from 480 nm
LEDs (18 W, 23 mW/cm2). The reaction progress was monitored
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 6 of 9
by thin layer chromatography or gas chromatography. Upon
completion of the reaction, the mixture was diluted with diethyl
ether and washed with brine. The layers were separated, and the
organic layer was concentrated in vacuo to give a crude residue
that was purified by silica gel column chromatography to give the
corresponding trifluoromethylating product 3.
1.85–1.77 (m, 2H), 1.65–1.60 (m, 2H); 13C{1H} NMR (151 MHz,
3
1
2
3
4
5
6
7
8
CDCl3) δ 166.9, 140.4 (q, J
= 6.7 Hz), 133.4, 130.7, 129.9,
C-F
1
2
128.7, 122.5 (q, J
= 269.8 Hz), 119.2 (q, J
= 33.2 Hz),
C-F
C-F
64.8, 31.4, 28.6, 24.9; 19F NMR (564 MHz, CDCl3) δ 64.03; IR
(neat): νmax = 2883, 1692, 1210, 1186, 944 cm-1; Rf = 0.45
(hex:EtOAc = 8:1).
3. Synthesis of perfluoroalkylated alkenes (4a, 5a, 4c, 5c, 4j, 5j).
(E)-4-bromo-N-(4,4,4-trifluorobut-2-en-1-yl)benzamide
(3d):9a
1
white solid (138 mg, 90%); H NMR (600 MHz, CDCl3) δ 7.66
(d, J = 8.6 Hz, 2H), 7.60 (d, J = 8.6 Hz, 2H), 6.47 (dtq, J = 15.9,
A flame-dried tube equipped with a magnetic stirring bar was
charged with argon. The substrate (2: 0.5 mmol), tri(9-
anthryl)borane (0.5 mol%: 2.7 mg), DBU (1.0 mmol, 152.5 uL),
and CH3CN (2.5 mL, 0.2 M) were added to the tube. Then, the
fluoroalkylating reagents (1.0 mmol) was added. The mixture was
stirred at room temperature and irradiated in a distance of 15 cm
from 480 nm LEDs (18 W, 23 mW/cm2). The reaction progress
was monitored by thin layer chromatography and gas
chromatography. Upon completion of the reaction, the mixture
was diluted with diethyl ether and washed with brine. The layers
were separated, and the organic layer was concentrated in vacuo
to give a crude residue that was purified by silica gel column
chromatography to give the corresponding perfluoroalkylating
product 4 and 5.
7.4, 4J H-F = 2.1 Hz, 1H), 6.24 (s, 1H), 5.81 (dqt, J = 15.9, 3J H-F
=
9
6.4, J = 2.0 Hz, 1H), 4.23–4.20 (m, 2H); 13C{1H} NMR (151
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
3
MHz, CDCl3) δ 166.7, 136.4 (q, J
= 6.3 Hz), 132.7, 132.2,
C-F
1
2
128.8, 126.9, 122.9 (q, J
= 270.5 Hz), 120.1 (q, J
= 34.2
C-F
C-F
Hz), 40.2; 19F NMR (564 MHz, CDCl3) δ −64.51; IR (neat): νmax
= 3184, 1693, 1578, 1283, 946, 665 cm-1; Rf = 0.34 (hex:EtOAc =
2:1).
(E)-4-chloro-N-(4,4,4-trifluorobut-2-en-1-yl)benzamide
(3e):9a
1
white solid (113 mg, 86%); H NMR (600 MHz, CDCl3) δ 7.73
(d, J = 8.5 Hz, 2H), 7.42 (d, J = 8.5 Hz, 2H), 6.45 (dtq, J = 15.6,
5.2, 4J H-F = 2.0 Hz, 1H), 6.40 (bs, 1H), 5.79 (dqt, J = 15.6, 3J H-F
= 6.4, J = 1.8 Hz, 1H), 4.21−4.18 (m, 2H); 13C{1H} NMR (151
3
4. Synthesis of trifluoromethylated heterocycles (7a, 7b).
MHz, CDCl3) δ 166.9, 138.7, 136.6 (q, J
= 6.4 Hz), 132.5,
C-F
1
2
129.4, 128.8, 122.2 (q, J
= 270.4 Hz), 120.3 (q, J
= 34.3
C-F
C-F
A flame-dried tube equipped with a magnetic stirring bar was
charged with argon. The substrate (6: 0.5 mmol), tri(9-
anthryl)borane (0.5 mol%: 2.7 mg), TMEDA (1.0 mmol, 150 uL),
and CH3CN (2.5 mL, 0.2 M) were added to the tube. CF3I (1.5
mmol, 37.5 mL) was then delivered into the reaction mixture
using a gastight syringe. The mixture was stirred at room
temperature and irradiated in a distance of 15 cm from 480 nm
LEDs (18 W, 23 mW/cm2). The reaction progress was monitored
by thin layer chromatography and gas chromatography. Upon
completion of the reaction, the mixture was diluted with diethyl
ether and washed with brine. The layers were separated, and the
organic layer was concentrated in vacuo to give a crude residue
that was purified by silica gel column chromatography to give the
corresponding trifluoromethylating product 7.
Hz), 40.5; 19F NMR (564 MHz, CDCl3) δ −64.50; IR (neat): νmax
= 3260, 3046, 1702, 1345, 939, 735 cm-1; Rf = 0.33 (hex:EtOAc =
4:1).
(E)-2-phenyl-N-(4,4,4-trifluorobut-2-en-1-yl)acetamide
colorless oil (114 mg, 94%); H NMR (600 MHz, CDCl3) δ 7.37
(3f):9a
1
(dd, J = 7.6, 7.3 Hz, 2H), 7.32 (d, J = 7.3 Hz, 1H), 7.27 (d, J = 7.6
4
Hz, 2H), 6.30 (dtq, J = 15.7, 4.9, J
= 2.5 Hz, 1H), 5.72 (s,
H-F
3
1H), 5.57 (dq, J = 12.6, J
= 6.3 Hz, 1H), 3.97–3.92 (m, 2H),
H-F
3.61 (s, 2H); 13C{1H} NMR (151 MHz, CDCl3) δ 171.3, 136.5 (q,
3J
= 6.4 Hz), 134.7, 129.4, 127.8, 125.6, 122.1 (q, J
=
1
C-F
C-F
2
269.6 Hz), 119.3 (q, J
= 34.1 Hz), 43.8, 39.7; 19F NMR (564
C-F
MHz, CDCl3) δ 64.21; IR (neat): νmax = 3142, 2961, 1702, 1287,
936 cm-1; Rf = 0.36 (hex:EtOAc = 2:1).
5. Analytical Data for trifluoromethylated alkenes (3a-3m).
(E)-N-(4,4,4-trifluorobut-2-en-1-yl)octanamide (3g):9a colorless
(E)-1,1,1-trifluorohept-2-ene (3a):9a colorless oil (0.5 mmol scale:
109 mg, 93%); 1H NMR (600 MHz, CDCl3) δ 6.36 (dtq, J = 15.9,
6.9, 4J H-F = 2.4 Hz, 1H), 5.60 (dqt, J = 15.9, 3J H-F = 6.4, J = 1.6
Hz, 1H), 2.17–2.12 (m, 2H), 1.45–1.41 (m, 2H), 1.30–1.25 (m,
14H), 0.88 (t, J = 7.0 Hz, 3H); 13C{1H} NMR (151 MHz, CDCl3)
δ 141.1 (q, 3J C-F = 6.5 Hz), 123.4 (q, 1J C-F = 269.1 Hz), 118.6 (q,
1
oil (111 mg, 88%); H NMR (600 MHz, CDCl3) δ 6.37 (dtq, J =
15.6, 6.8, 4J H-F = 2.0 Hz, 1H), 5.72 (dqt, J = 15.6, 3J H-F = 6.4, J =
1.8 Hz, 1H), 5.61 (bs, 1H), 4.03−3.99 (m, 2H), 2.21 (t, J = 7.7 Hz,
2H), 1.64 (tt, J = 7.7, 7.4 Hz, 2H), 1.34−1.23 (m, 8H), 0.86 (t, J =
6.9 Hz, 3H); 13C{1H} NMR (151 MHz, CDCl3) δ 173.1, 136.6 (q,
1
2
3J
= 6.3 Hz), 123.7 (q, J
= 270.3 Hz), 119.3 (q, J
=
2J
= 33.2 Hz), 32.1, 31.7, 29.8, 29.7, 29.6, 29.5, 29.3, 28.2,
C-F
C-F
C-F
C-F
34.1 Hz), 39.4, 36.6, 31.7, 29.3, 29.1, 25.7, 22.6, 14.1; 19F NMR
(564 MHz, CDCl3) δ −64.22; IR (neat): νmax = 3143, 3042, 2885,
1699, 1335, 923 cm-1; Rf = 0.38 (hex:EtOAc = 2:1).
22.9, 14.3; 19F NMR (564 MHz, CDCl3) δ 63.91; IR (neat): νmax
= 2883, 1623, 1215, 930 cm-1; Rf = 0.95 (only hexanes).
(E)-(5,5,5-trifluoropent-3-en-1-yl)benzene (3b):9a colorless oil (88
(E)-7,7,7-trifluorohept-5-en-1-ol (3h):9a colorless oil (65 mg,
77%); 1H NMR (600 MHz, CDCl3) δ 6.35 (dtq, J = 15.6, 6.5, 4J H-
F = 2.0 Hz, 1H), 5.60 (dqt, J = 15.6, 3J H-F = 6.3, J = 1.5 Hz, 1H),
1
mg, 88%); H NMR (600 MHz, CDCl3) δ 7.31 (dd, J = 7.5, 7.4
Hz, 2H), 7.22 (t, J = 7.4 Hz, 1H), 7.18 (d, J = 7.5 Hz, 2H), 6.42
(dtq, J = 15.7, 6.7, 4J H-F = 2.1 Hz, 1H), 5.64 (dqt, J = 15.7, 3J H-F
3.64 (t, J = 6.3 Hz, 2H), 2.20–2.14 (m, 2H), 1.62–1.48 (m, 5H);
= 6.4, J = 1.6 Hz, 1H), 2.77 (t, J = 7.5 Hz, 2H), 2.51–2.46 (m, 2H);
3
13C{1H} NMR (151 MHz, CDCl3) δ 140.3 (q, J
= 6.5 Hz),
3
13C{1H} NMR (151 MHz, CDCl3) δ 140.7, 139.8 (q, J
= 6.6
C-F
C-F
122.6 (q, 1J C-F = 269.9 Hz), 118.7 (q, 2J C-F = 33.7 Hz), 62.5, 32.0,
31.2, 24.3; 19F NMR (564 MHz, CDCl3) δ 64.01; IR (neat): νmax
= 3128, 2963, 1691, 951 cm-1.
Hz), 128.7, 128.5, 126.5, 123.2 (q, 1J C-F = 270.1 Hz), 119.1 (q, 2J
C-F = 33.1 Hz), 34.6, 33.4; 19F NMR (564 MHz, CDCl3) δ 64.04;
IR (neat): νmax = 2994, 1696, 1239, 1163, 946 cm-1; Rf = 0.74
(only hexanes).
(E)-4-((4,4,4-trifluorobut-2-en-1-yl)oxy)butan-1-ol
(3i):9a
1
colorless oil (71 mg, 72%); H NMR (600 MHz, CDCl3) δ 6.42
(dtq, J = 15.8, 4.0, 4J H-F = 2.0 Hz, 1H), 5.91 (dqt, J = 15.8, 3J H-F
= 6.8, J = 1.8 Hz, 1H), 4.13−4.06 (m, 2H), 3.66 (t, J = 6.0 Hz, 2H),
3.52 (t, J = 6.0 Hz, 2H), 2.04 (s, 1H), 1.75−1.61 (m, 4H); 13C{1H}
NMR (151 MHz, CDCl3) δ 136.9 (q, 3J C-F = 6.5 Hz), 123.5 (q, 1J
C-F = 270.1 Hz), 118.6 (q, 2J C-F = 34.2 Hz), 71.3, 68.4, 62.9, 29.7,
(E)-5,5,5-trifluoropent-3-en-1-yl benzoate (3c):9a colorless oil
(121 mg, 88%); 1H NMR (600 MHz, CDCl3) δ 8.04 (d, J = 7.4 Hz,
2H), 7.56 (t, J = 7.4 Hz, 1H), 7.45 (dd, J = 8.0, 7.4 Hz, 2H), 6.39
(dtq, J = 15.7, 6.8, 4J H-F = 2.0 Hz, 1H), 5.65 (dqt, J = 15.7, 3J H-F
= 6.4, J = 1.6 Hz, 1H), 4.35 (t, J = 6.5 Hz, 2H), 2.26–2.21 (m, 2H),
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The Journal of Organic Chemistry
26.3; 19F NMR (564 MHz, CDCl3) δ −65.32; IR (neat): νmax
3382, 2869, 1692, 1321, 1119 cm-1.
=
-111.52, -124.56, -125.85; IR (neat): νmax = 2970, 2361, 1739,
1
1229, 910 cm-1; Rf = 0.89 (only hexanes).
2
3
4
5
6
7
8
9
(E)-1-(3,3,3-trifluoroprop-1-en-1-yl)azepan-2-one (3j):16 white
solid (98 mg, 95%); H NMR (600 MHz, CDCl3) δ 7.94 (d, J =
(E)-7,7,8,8,9,9,9-heptafluoronon-5-en-1-yl
benzoate
(4c):
1
1
colorless oil (174 mg, 93%); H NMR (600 MHz, CDCl3) δ 8.04
(d, J = 7.6 Hz, 2H), 7.57 (t, J = 7.6 Hz, 1H), 7.45 (dd, J = 7.7, 7.6
Hz, 2H), 6.46–6.39 (m, 1H), 5.67–5.60 (m, 1H), 4.35 (t, J = 6.4
Hz, 2H), 2.32–2.28 (m, 2H), 1.83–1.79 (m, 2H), 1.67–1.61 (m,
14.7 Hz, 1H), 5.08 (dq, J = 14.7, 3J H-F = 6.1 Hz, 1H), 3.57 (t, J =
4.9 Hz, 2H), 2.69–2.67 (m, 2H), 1.78–1.70 (m, 6H); 13C{1H}
NMR (151 MHz, CDCl3) δ 175.0, 134.4 (q, 3J C-F = 7.3 Hz), 125.1
(q, 1J C-F = 267.8 Hz), 97.0 (q, 2J C-F = 34.4 Hz), 45.6, 37.2, 29.4,
27.3, 23.6; 19F NMR (564 MHz, CDCl3) δ 59.85; IR (neat): νmax
= 2937, 1655, 1343, 969 cm-1; Rf = 0.38 (hex:EtOAc = 4:1).
2H); 13C{1H} NMR (151 MHz, CDCl3) δ 166.8, 142.6 (t, J
=
C-F
8.4 Hz), 133.2, 130.5, 129.7, 128.5, 117.4 (t, J
= 8.4 Hz),
C-F
114.1 (t, J
= 29.5 Hz), 113.8, 64.6, 31.7, 28.3, 24.8 (carbon
C-F
peaks of –C3F7 are omitted due to complicated C-F splitting); 19F
NMR (564 MHz, CDCl3) δ -80.40, -112.42, -127.92; IR (neat):
νmax = 2970, 2361, 1739, 1366, 1228, 903 cm-1; HRMS m/z (EI)
calc. for C16H15F7O2 [M+] 372.0960, found 372.0958; Rf = 0.70
(hex:EtOAc = 4:1).
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(E)-tert-butyldimethyl((7,7,7-trifluorohept-5-en-1-yl)oxy)silane
1
(3k):9a colorless oil (127 mg, 90%); H NMR (600 MHz, CDCl3)
δ 6.38 (dtq, J = 15.6, 6.5, 4J H-F = 2.0 Hz, 1H), 5.62 (dqt, J = 15.6,
3J
= 6.1, J = 1.6 Hz, 1H), 3.62 (t, J = 6.0 Hz, 2H), 2.21–2.14
H-F
(m, 2H), 1.55–1.49 (m, 4H), 0.89 (s, 9H), 0.05 (s, 6H); 13C{1H}
NMR (151 MHz, CDCl3) δ 140.6 (q, 3J C-F = 6.3 Hz), 122.9 (q, 1J
C-F = 269.7 Hz), 118.6 (q, 2J C-F = 32.1 Hz), 62.7, 32.1, 31.2, 25.9,
24.4, 18.4, 5.3; 19F NMR (564 Hz, CDCl3) δ 63.96; IR (neat):
νmax = 3002, 2970, 2360, 1738, 1366, 1228 cm-1.
(E)-7,7,8,8,9,9,10,10,10-nonafluorodecyl benzoate (5c): colorless
oil (191 mg, 90%); 1H NMR (600 MHz, CDCl3) δ 8.04 (d, J = 7.8
Hz, 2H), 7.56 (t, J = 7.8 Hz, 1H), 7.45 (dd, J = 8.3, 7.8 Hz, 2H),
3
6.43 (ddt, J = 15.8, 6.7, J
= 2.1 Hz, 1H), 5.69–5.60 (m, 1H),
H-F
4.35 (t, J = 6.4 Hz, 2H), 2.32–2.28 (m, 2H), 1.83–1.78 (m, 2H),
1.67–1.61 (m, 2H); 13C{1H} NMR (151 MHz, CDCl3) δ 166.6,
142.5 (t, J C-F = 9.2 Hz), 132.9, 130.3, 129.5, 128.4, 117.4 (t, J C-F
= 22.8 Hz), 64.4, 31.6, 28.2, 24.6 (carbon peaks of –C4F9 are
omitted due to complicated C-F splitting); 19F NMR (564 MHz,
CDCl3) δ -81.14, -111.59, -124.46, -125.81; IR (neat): νmax = 2970,
2360, 1739, 1366, 1264, 911 cm-1; HRMS m/z (EI) calc. for
(E)-7,7,7-trifluorohept-5-en-1-yl 4-methylbenzenesulfonate (3l):9a
1
colorless oil (155 mg, 96%); H NMR (600 MHz, CDCl3) δ 7.78
(d, J = 8.2 Hz, 2H), 7.34 (d, J = 8.2 Hz, 2H), 6.28 (dtq, J = 15.7,
6.8, 4J H-F = 2.1 Hz, 1H), 5.56 (dqt, J = 15.7, 3J H-F = 6.4, J = 1.9
Hz, 1H), 4.03 (t, J = 6.2 Hz, 2H), 2.44 (s, 3H), 2.10 (dt, J = 7.4,
2.5 Hz, 2H), 1.67–1.63 (m, 2H), 1.52–1.43 (m, 2H); 13C{1H}
3
C17H15F9O2 [M+] 422.0928, found 422.0931; Rf
(hex:EtOAc = 4:1).
= 0.77
NMR (151 MHz, CDCl3) δ 144.8, 139.6 (q, J
= 6.5 Hz),
C-F
133.0, 129.8, 127.8, 121.9 (q, 1J C-F = 269.3 Hz), 119.1 (q, 2J C-F
=
33.2 Hz), 69.9, 30.6, 28.1, 23.8, 21.5; 19F NMR (564 MHz,
CDCl3) δ 64.07; IR (neat): νmax = 2969, 2361, 1738, 1356, 1113,
932 cm-1; Rf = 0.56 (hex:EtOAc = 4:1).
(E)-1-(3,3,4,4,5,5,5-heptafluoropent-1-en-1-yl)azepan-2-one (4j):
white solid (141 mg, 92%); 1H NMR (600 MHz, CDCl3) δ 7.92 (d,
J = 14.7 Hz, 1H), 5.02–4.94 (m, 1H), 3.63–3.57 (m, 2H), 2.72–
2.66 (m, 2H), 1.82–1.69 (m, 6H); 13C{1H} NMR (151 MHz,
(E,Z)-5-(trifluoromethyl)dec-5-ene (3m):9a colorless oil (94 mg,
1
CDCl3) δ 174.9, 135.6 (t, J
= 9.9 Hz), 117.3 (q, J
= 32.2
C-F
C-F
90%); H NMR (600 MHz, CDCl3) δ 6.08–6.04 (m, 1H), 2.26–
Hz), 115.7 (t, J C-F = 30.6 Hz), 94.4 (t, J C-F = 23.5 Hz), 45.6, 37.2,
29.4, 27.3, 23.5 (carbon peaks of –C3F7 are omitted due to
complicated C-F splitting); 19F NMR (564 MHz, CDCl3) δ -80.24,
-108.83, -127.54; IR (neat): νmax = 2970, 2361, 1739, 1366, 1291,
904 cm-1; HRMS m/z (EI) calc. for C11H12F7NO [M+] 307.0807,
found 307.0805; Rf = 0.42 (hex:EtOAc = 4:1).
2.20 (m, 3H), 1.45–1.35 (m, 12H), 0.94–0.91 (m, 3H); 5.68–5.65
(m, 1H), 2.16–2.10 (m, 3H), 1.43–1.30 (m, 12H), 0.91–0.89 (m,
3H); 13C{1H} NMR (151 MHz, CDCl3) δ 137.7, 32.4, 31.8, 31.4,
31.2, 28.2, 27.2, 25.7, 22.9, 22.6, 22.4, 22.3, 14.1; 19F NMR (564
MHz, CDCl3) δ 59.69; 66.88; IR (neat): νmax = 2970, 2361,
1739, 1366, 1229, 911 cm-1.
(E)-1-(3,3,4,4,5,5,6,6,6-nonafluorohex-1-en-1-yl)azepan-2-one
1
(5j): white solid (161 mg, 90%); H NMR (600 MHz, CDCl3) δ
6. Analytical Data for perfluoroalkylated alkenes (4a, 5a, 4c, 5c,
4j, 5j).
7.93 (d, J = 14.7 Hz, 1H), 5.02–4.95 (m, 1H), 3.61 (d, J = 4.9 Hz,
2H), 2.71–2.68 (m, 2H), 1.81–1.70 (m, 6H); 13C{1H} NMR (151
(E)-1,1,1,2,2,3,3-heptafluoropentadec-4-ene (4a):17 colorless oil
MHz, CDCl3) δ 174.9, 135.7 (t, J
= 10.5 Hz), 117.4, 115.6,
C-F
1
(0.5 mmol scale: 151 mg, 90%); H NMR (600 MHz, CDCl3) δ
94.5 (t, J C-F = 23.9 Hz), 45.6, 37.2, 29.4, 27.3, 23.6 (carbon peaks
of –C4F9 are omitted due to complicated C-F splitting); 19F NMR
(564 MHz, CDCl3) δ -81.09, -108.00, -124.02, -125.67; IR (neat):
νmax = 2970, 2361, 1739, 1366, 1230, 903 cm-1; HRMS m/z (EI)
calc. for C12H12F9NO [M+] 357.0775, found 357.0778; Rf = 0.41
(hex:EtOAc = 4:1).
6.44–6.37 (m, 1H), 5.58 (dt, J = 15.3, 3J H-F = 12.4 Hz, 1H), 2.22–
2.16 (m, 2H), 1.47–1.42 (m, 2H), 1.34–1.24 (m, 14H), 0.88 (t, J =
7.1 Hz, 3H); 13C{1H} NMR (151 MHz, CDCl3) δ 143.2 (t, J C-F
=
9.0 Hz), 116.4 (t, J
= 22.9 Hz), 31.9, 31.8, 29.5, 29.4, 29.3,
C-F
29.2, 28.9, 27.9, 22.6, 14.0 (carbon peaks of –C3F7 are omitted
due to complicated C-F splitting); 19F NMR (564 MHz, CDCl3) δ
-80.46, -112.35, -128.02; IR (neat): νmax = 2970, 2360, 1739,
1228, 904 cm-1; Rf = 0.89 (only hexanes).
7. Analytical Data for trifluoromethylated heterocycles (7b).
3-methyl-2-(trifluoromethyl)-1H-indole (7b):18 white solid (0.5
mmol scale: 85 mg, 85%); 1H NMR (600 MHz, CDCl3) δ 8.18 (s,
1H), 7.65 (d, J = 8.1 Hz, 1H), 7.39 (d, J = 8.2 Hz, 1H), 7.33 (dd,
J = 8.1, 7.8 Hz, 1H), 7.20 (dd, J = 8.2, 7.8 Hz, 1H), 2.45 (q, 5J H-F
= 1.8 Hz, 3H); 13C{1H} NMR (151 MHz, CDCl3) δ 135.4, 128.3,
(E)-1,1,1,2,2,3,3,4,4-nonafluorohexadec-5-ene (5a):17 colorless oil
(182 mg, 94%); 1H NMR (600 MHz, CDCl3) δ 6.44–6.38 (m, 1H),
5.59 (dt, J = 15.7, 3J H-F = 12.5 Hz, 1H), 2.23–2.17 (m, 2H), 1.48–
1.43 (m, 2H), 1.33–1.24 (m, 14H), 0.89 (t, J = 7.0 Hz, 3H);
13C{1H} NMR (151 MHz, CDCl3) δ 143.6 (t, J
= 8.6 Hz),
C-F
1
2
124.9, 122.3 (q, J
= 269.6 Hz), 121.7 (q, J
= 36.8 Hz),
C-F
C-F
116.9 (t, J
= 22.8 Hz), 32.2, 32.1, 29.9, 29.8, 29.7, 29.6, 29.2,
C-F
120.6, 120.3, 114.3 (q, 3J C-F = 3.0 Hz), 111.8, 8.5; 19F NMR (564
MHz, CDCl3) δ -58.69; IR (neat): νmax = 3391, 2926, 1593, 903
cm-1; Rf = 0.71 (hex:EtOAc = 10:1).
28.2, 22.9, 14.3 (carbon peaks of –C4F9 are omitted due to
complicated C-F splitting); 19F NMR (564 MHz, CDCl3) δ -81.21,
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Applications in Organic Synthesis. Chem. Rev. 2013, 113, 5322-
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Stephenson, C. R. J.; Yoon, T. R.; MacMillan, D. W. C. Eds.
Visible Light Photocatalysis in Organic Chemistry; John Wiley &
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(5) Examples of visible-light-induced trifluoromethylation
reactions using organic dyes, see: (a) Fu, W.; Guo, W.; Zou, G.;
Xu, C. Selective trifluoromethylation and alkynylation of
tetrahydroisoquinolines using visible light irradiation by Rose
Bengal. J. Fluorine Chem. 2012, 140, 88-94. (b) Pitre, S. P.;
McTiernan, C. D.; Ismaili, H.; Scaiano, J. C. Metal-Free
Photocatalytic Radical Trifluoromethylation Utilizing Methylene
Blue and Visible Light Irradiation. ACS Catal. 2014, 4, 2530-
2535. (c) Park, G. R.; Choi, Y.; Choi, M. G.; Chang, S. K.; Cho,
E. J. Metal-Free Visible-Light-Induced Trifluoromethylation
Reactions. A. J. Org. Chem. 2017, 6, 436-440. (d) Noto, N.;
Koike, T.; Akita, M. Metal-free di- and tri-fluoromethylation of
alkenes realized by visible-light-induced perylene photoredox
catalysis. Chem. Sci. 2017, 8, 6375-6379 (e) Noto, N.; Yuya, T.;
Koike, T.; Akita, M. Strongly Reducing (Diarylamino)anthracene
ASSOCIATED CONTENT
Supporting Information
The Supporting Information is available free of charge on
the ACS Publications website.
Additional experiments, analytic data for fluoroalkylated
compounds, and NMR spectra (PDF)
AUTHOR INFORMATION
Corresponding Author
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*E-mail: odds2@ewha.ac.kr (Y. You)
*E-mail: ejcho@cau.ac.kr (E. J. Cho)
ORCID
Youngmin You: 0000-0001-5633-6599
Eun Jin Cho: 0000-0002-6607-1851
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENT
We gratefully acknowledge the support from National
Research Foundation of Korea for Y. You [NRF-
2015M3D1A1070639, NRF-2019R1A2C2003969] and E. J.
Cho [NRF-2012M3A7B4049657, NRF-2014011165, NRF-
2017R1A2B2004082].
Catalyst
for
Metal-Free
Visible-Light
Photocatalytic
Fluoroalkylation. ACS Catal. 2018, 8, 9408-9419. (f) Ghiazza, C.;
Monnereau, C.; Khrouz, L.; Médebielle, M.; Billard, T.; Tlili, A.
New Avenues in Radical Trifluoromethylselenylation with
Trifluoromethyl Tolueneselenosulfonate. Synlett 2018, 30, 777-
782.
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