One-pot preparation of fluorinated propargylamines under microwave irradiation and solvent-free conditions

Article abstract of DOI:10.1016/j.jfluchem.2008.06.015

A facile one-pot method has been developed for the synthesis of fluorine-containing propargylamines by a three-component coupling of fluorinated aldehydes, amines, and alkynes, in the presence of copper (I) chloride under microwave irradiation and solvent-free condition. This process is an efficient alternative to traditional thermal reaction. All new compounds are fully characterized by spectral methods.

Full text of DOI:10.1016/j.jfluchem.2008.06.015

Journal of Fluorine Chemistry 129 (2008) 695–700
Contents lists available at ScienceDirect
Journal of Fluorine Chemistry
journal homepage: www.elsevier.com/locate/fluor
One-pot preparation of fluorinated propargylamines under microwave
irradiation and solvent-free conditions
Wei-Qiong Du a, Jian-Min Zhang a, Ran Wu a, Qin Liang a, Shi-Zheng Zhu b,
*
a Department of Chemistry, School of Science, Shanghai University, Shanghai, China
b Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 354 Fenglin Lu, Shanghai 200032, China
A R T I C L E I N F O
A B S T R A C T
Article history:
A facile one-pot method has been developed for the synthesis of fluorine-containing propargylamines by
a three-component coupling of fluorinated aldehydes, amines, and alkynes, in the presence of copper (I)
chloride under microwave irradiation and solvent-free condition. This process is an efficient alternative
to traditional thermal reaction. All new compounds are fully characterized by spectral methods.
ß 2008 Elsevier B.V. All rights reserved.
Received 14 February 2008
Received in revised form 4 June 2008
Accepted 6 June 2008
Available online 24 June 2008
Keywords:
Fluorinated propargylamines
Microwave
Solvent free
One-pot reaction
Three-component coupling
1. Introduction
[6]. This A3 coupling reaction can be catalyzed by several transition
metal catalysts via C–H activation. such as, silver salts [7], gold
The increasing environmental consciousness of the chemical
community has led to the search for more efficient and environ-
mentally friendly methods for chemical synthesis. Microwave-
promoted reactions, especially those run in water or solvent-free
conditions have been attracting increasing research interest from
chemists in recent years, not only because these reactions exhibit
some particular or unexpected reactivities in some cases but also
because they are significantly useful for green chemistry [1]. Since
the first report on the use of microwave heating to accelerate
organic chemical transformations by the groups of Gedye and
Giguere/Majetich [2], thousands of articles have been published
in the area of microwave assisted organic synthesis. In our
corresponding investigations, we have reported a microwave-
promoted synthesis of 2-pentafluorophenylquinoline derivatives
salts [8], and copper salts [9]. Also a variety of chiral ligands have
been used in this reaction to gain high asymmetric induction [10].
However, these procedures require a long reaction time (4–24 h),
and some of these catalysts are expensive. Recently, an ultrasound-
promoted three-component reaction for the preparation of
propargylamines using CuI as the catalyst was reported by
Sreedhar [11b], the reaction time was shorted to 45–75 min. To
our best knowledge, the preparation of fluorine-containing
propargylamines has been studied rarely.
As a part of our work on the microwave-promoted reactions
in organic synthesis, we describe a fast and efficient one-pot
procedure for the synthesis of fluorinated propargylamines under
microwave irradiation and solvent-free conditions.
[3] and
a
-aminoalkyl phosphonates [4].
2. Results and discussion
More recently, one-pot multi-component reactions (MCR) as
an versatile strategy in organic synthesis have received much
attention, for example, the three-component coupling of the
aldehyde, the alkyne and the amine (A3 coupling) [5] gave
propargylamines, which are important synthetic intermediates for
potential therapeutic agents and polyfunctional amino derivatives
The microwave-promoted three components coupling experi-
ment was performed by irradiation of a mixture of aldehydes,
amines, and alkynes in the presence of CuCl (30 mol%) in a sealed
tube to afford the desired propargylamines in 2–15 min (Scheme 1).
Initially, different reaction conditions were screened and the
coupling of pentafluorophenylaldehyde (1d), p-fluoroaniline (2e)
and phenylacetylene (3) was selected as model reaction (Table 1).
It was found that the molar ratio of aldehyde:amine:alk-
yne = 1:1.2:1.5 was the best reaction ratio. Even when 2 equiv. of
* Corresponding author. Tel.: +86 21 54925184; fax: +86 21 64166128.
E-mail address: zhusz@mail.sioc.ac.cn (S.-Z. Zhu).
0022-1139/$ – see front matter ß 2008 Elsevier B.V. All rights reserved.
doi:10.1016/j.jfluchem.2008.06.015

696
W.-Q. Du et al. / Journal of Fluorine Chemistry 129 (2008) 695–700
Scheme 1. Synthesis of the fluorinated propargylamines.
Table 1
The reaction of m-fluorobenzaldehyde (1a), p-fluoroaniline (2e) and phenylacetylene
Entry
Mole ratio
Catalyst
Atmosphere
Microwave power (W)
Time (min)
Solvent
Yield (%)
1a
2e
3
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
CuCl
CuI
–
800
800
800
800
800
800
300
400
450
800
800
800
14
14
14
14
14
14
30
30
30
30
30
30
–
Trace
20
1
1
N2
N2
N2
N2
N2
N2
N2
N2
N2
N2
N2
–
3
1.2
1.2
1.2
1.2
1.2
1.2
1.2
1.2
1.2
1.2
1
CuCl
CuCl
CuCl
CuI
–
30
4
1.5
2
–
56
5
–
50
6
1.5
1.5
1.5
1.5
1.5
1.5
1.5
–
55
7
CuCl
CuCl
CuCl
CuCl
CuCl
CuCl
–
Trace
10
8
–
9
–
30
10
11
12
Toluene
DMF
H2O
30
25
Trace
the alkynes were used in the reaction, the reaction intermediate
product imines (Ar1CH NAr2) were not completely consumed (as
monitored by TLC). On the basis of some literature reports, alkynes
could come into small amount of oligomerization in the presence
of metal catalyst [12]. Thus, more excess alkynes did not increase
the yield of product (Table 1 entry 5). Additionally, in our
denote the hydrogen of –CH– and the active hydrogen of –NH–. The
19F NMR spectrum is very similar to the starting aldehyde and
amine. The 13C NMR shows signals at 88.7–84.8 and 85.9–
84.3 ppm for two sp1 carbon atoms of CBB C. In this spectrum, the
fluorine contiguous carbons always show first-order and second-
order coupling. For example, in the 13C NMR of compound 4ac,
162.2 and 164.1 represent the first-order coupling of the carbon of
experiment
a sealed tube was necessary for this reaction;
Otherwise, a low conversion and more by-products were observed.
Some A3 coupling reactions proceeded very well either in water
[11b] or in an organic solvent such as toluene [9d] and DMF [7].
However, in our case when the reaction was carried out in toluene
(30%), DMF (25%) or in water (trace) gave low yield product. We
found a solvent-free condition offered a fine outcome. The catalyze
effect of CuCl is the same as CuI.
Having identified the optimum reaction conditions, the
substrate scope of this method was examined (Table 2). A study
on the aniline substrates revealed that the reactions with the
anilines with electron-withdrawing groups, such as –F and NO2,
gave much higher yields than those with electron-donating
groups. For the substituents of the aromatic aldehydes, good
yields were obtained with electron-withdrawing groups, while
poor yields were given with electron-donating groups.
Subsequently, we could afford the desired yield in 2–15 min
under microwave-promoted conditions, while very low yield could
be gained in traditional thermal reactions. For example, only trace
product was achieved after heating in toluene at 60 8C for 10 h.
All products (4ae–4dd) are fully characterized by standard
spectroscopic methods. The IR shows single acutely middle
intension signal at 3454–3319 cmÀ1 for vibration of –NH. The
1H NMR shows signals at 5.83–5.41 and 5.26–4.07 ppm, these
–Ar1–F (
represent the first-order and second-order coupling of –Ar2–F
d = 163.3, d, J = 246 Hz). 151.8, 151.7, 149.9 and 159.8
(d
= 150.8, dd, 1J = 244 Hz, 2J = 14 Hz). The EI-MS shows a weak
molecular ion peak M+ and the basic peak M+–ArNH or M+–
C6H5CBB CH.
The molecular structure of 4de was further determined by X-
ray crystal diffraction analysis. Its molecule structure and the
packing map was shown in Figs. 1 and 2. The selected bond lengths
˚
(A) and band angles (8) for compound 4de was listed in Table 3.
This compound shows strong intermolecular hydrogen bonding
˚
between N–H. . .N (dN–H. . .N = 2.307 A; nN–H. . .N = 158.38), and the
intramolecular weak hydrogen bonding between C–H. . .F. (dC–
˚
H. . .F = 2.352, 2.480 and 2.580 A; nC–H. . .F = 110.18, 148.88 and
149.98).
On the basis of the above experimental results, together with
some literature reports [7,11a], a tentative mechanism was
proposed as shown in Scheme 2. The MW irradiation first
promoted CuCl catalyzed activation of the C–H bond of alkyne
to give the copper acetylide A as well as the formation of iminie
from the condisation of aldehyde and aniline. Then, the copper
acetylide intermediate A attacked iminium B which is protonated
by HCl to give the final propargylamine with releasing the Cu (I)
catalyst for further cycle of reactions.

W.-Q. Du et al. / Journal of Fluorine Chemistry 129 (2008) 695–700
697
Table 2
One-pot preparation of fluorinated propargylamines 4 under microwave irradiationa
Entry
Aldehyde
Amine
Alkyne
Product
Time (min)
Yield (%)b
1
4ae
6
91
2
4ab
2
89
3
4ad
16
51
4
5
4ba
4cc
3
5
90
43
6
7
8
9
4ac
4de
4dc
4db
4
14
13
7
70
56
90
70
10
4dd
11
76

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W.-Q. Du et al. / Journal of Fluorine Chemistry 129 (2008) 695–700
Table 2 (Continued )
Entry
Aldehyde
Amine
Alkyne
Product
Time (min)
Yield (%)b
Trace
11
4df
15
12
4ec
15
Trace
a
Power 800 W.
b
Isolated yield based on aldehyde 1.
Fig. 1. The crystal structure of compound 4de shows the inter- and intramolecular hydrogen bonds.
Fig. 2. The packing map of 4de.
Scheme 2. Tentative reaction mechanism of three-component coupling reaction.

W.-Q. Du et al. / Journal of Fluorine Chemistry 129 (2008) 695–700
699
Table 3
125.2 (d, J = 3 Hz), 122.5 (d, J = 8 Hz), 118.5 (d, J = 22 Hz), 116.1 (d,
J = 22 Hz), 114.7 (d, J = 22 Hz), 87.7 (s), 85.7 (s), 51.0 (s); EI-MS: m/z
(%): 319 (M+, 1), 217 (M+–C6H5CBB CH, 100), 209 (M+–FC6H5NH, 28).
˚
Selected bond lengths (A) and band angles (8) for compound 4de
˚
Bond
Length (A)
Bond
Angle (8)
C(1)–N(1)
C(1)–C(16)
C(5)–C(6)
C(5)–H(5)
C(13)–F(1)
N(1)–H(1A)
1.449(6)
1.516(6)
1.374(7)
0.9300
N(1)–C(1)–C(16)
C(2)–C(1)–C(16)
N(1)–C(1)–H(1)
C(10)–N(1)–H(1A)
F(6)–C(21)–C(20)
C(3)–C(2)–C(1)
109.9(3)
110.4(4)
107.1
4.2.2. N-(4-Nitrophenyl)-3-amino-3-(3-fluorophenyl)-1-
phenylprop-1-yne (4ab)
IR (KBr, cmÀ1):
n
3349, 3059, 2917, 2224, 1598, 1483, 1321,
121.5
1295, 1109, 830, 753, 689; 1H NMR (500 MHz, CDCl3):
d
7.99 (d,
1.366(6)
0.8600
118.3(4)
178.4(5)
J = 9.0 Hz, 2H), 7.18–7.34 (m, 8H), 6.94–6.98 (m, 1H), 6.61 (m, 2H),
5.50 (d, J = 7.0 Hz, 1H), 5.03 (d, J = 6.0 Hz, 1H); 19F NMR (470 MHz,
CDCl3):
d
À111.5 to À111.4 (m, 1F); 13C NMR (125 MHz, CDCl3):
d
3. Conclusion
163.1 (d, J = 246 Hz), 151.4 (d, J = 3 Hz), 140.7 (d, J = 6 Hz), 139.2 (s),
131.8 (s), 130.7 (d, J = 8 Hz), 129.0 (s), 128.5 (s), 126.2 (s), 122.9 (d,
J = 4 Hz), 121.9 (s), 115.6 (d, J = 21 Hz), 114.3 (d, J = 22 Hz), 112.6
(s), 86.3 (s), 85.9 (s), 49.6 (s); EI-MS: m/z (%): 346 (M+, 2), 209 (M+–
NO2C6H4NH, 100); HRMS cacld. for C21H15N2O2F: 346.1118.
Found: 346.1115.
In summary, a microwave-promoted, rapid and efficient three-
component reaction for the preparation of fluorinated propargy-
lamines using CuCl as the catalyst in solvent-free condition has
been developed. The notable advantages of this procedure, such as
short reaction time, environmental friendly, cheap catalyst and
simple workup, make this method an attractive and useful in
organic synthesis. A further chemical transformation of the title
products is under investigation.
4.2.3. N-(3-Chlorophenyl)-3-amino-3-(3-fluorophenyl)-1-
phenylprop-1-yne (4ad)
IR (KBr, cmÀ1):
n
3411, 3060, 2963, 1595, 1486, 1260, 1091,
1020, 798, 687; 1H NMR (500 MHz, CDCl3):
7.52–7.54 (m, 1H),
7.03–7.37 (m, 10H), 6.60–6.77 (m, 2H), 5.47 (d, J = 7.0 Hz, 1H), 4.26
(d, J = 7.0 Hz, 1H); 19F NMR (470 MHz, CDCl3):
À112.1 to À112.0
(m, 1F); 13C NMR (125 MHz, CDCl3):
147.4 (s), 141.8 (d, J = 8 Hz),
d
4. Experimental
d
4.1. General experimental techniques and apparatus
d
135.0 (s), 131.8 (s), 130.4 (d, J = 8 Hz), 130.2 (s), 128.7 (s), 128.5 (s),
128.3 (s), 122.8 (d, J = 4 Hz), 122.3 (s), 118.8 (s), 115.2 (d, J = 21 Hz),
114.3 (d, J = 22 Hz), 114.0 (s), 112.3 (s), 87.1 (s), 85.7 (s), 50.1 (s); EI-
MS: m/z (%): 335 (M+, 4), 209 (M+–ClC6H4NH, 100); HRMS cacld. for
All reactions were performed in an improved domestic Sanyo,
EM-551S/550S, microwave oven (2450 MHz, 80–800 W). TLC was
performed on precoated silica gel F-254 plates (0.25 mm; E.
Merck), and product (s) and starting material(s) were detected by
viewing under UV light. Column chromatography was performed
on silica gel (300–400 mesh). Infrared spectra were recorded on an
AVATAR370 FT spectrophotometer (PerkinElmer, USA). NMR
spectra were determined with DRX500MHz spectrometer (Bruker,
USA), using solutions in deuterated chloroform with tetramethyl-
silane as the internal standard for 1H and 13C nuclei, respectively.
Low resolution mass spectrum or high resolution mass spectra
were obtained on Finnigan MAT-8430 instrument using the
electron impact ionization technique (70 eV). X-ray diffraction
C21H15NFCl: 335.0877. Found: 335.0885.
4.2.4. N-(3-Fluorophenyl)-3-amino-3-(4-nitrophenyl)-1-
phenylprop-1-yne (4ba)
IR (KBr, cmÀ1):
n
3405, 3075, 2962, 2204, 1618, 1519, 1346, 1149,
757, 689; 1H NMR (500 MHz, CDCl3):
8.22 (d, J = 8.5 Hz, 2H), 7.79
(d, J = 8.5 Hz, 2H), 7.10–7.42 (m, 6H), 6.39–6.50 (m, 3H), 5.55 (d,
d
J = 5.5 Hz, 1H), 4.47 (d, J = 5.5 Hz, 1H); 19F NMR (470 MHz, CDCl3):
d
À112.1 to À112.0 (m, 1F); 13C NMR (125 MHz, CDCl3):
d 163.7 (d,
J = 243 Hz), 146.6 (s), 142.3 (s), 132.6 (s), 131.8 (s), 128.5 (s), 128.1
(s), 124.1(s), 123.7(s), 122.0(s), 116.9(d,J = 4 Hz), 110.0 (d, J = 3 Hz),
105.7 (d, J = 29 Hz), 101.2 (d, J = 25 Hz), 86.5 (s), 82.2 (s), 50.1 (s); EI-
MS: m/z (%): 346 (M+, 2), 298 (M+–NO2, 100), 209 (M+–C6H5NO2, 74).
crystal structure analyses was obtained on Bruker SMART Apex II
˚
CCD diffractometer Mo K
a (l = 0.71073 A).
4.2. Synthesis of propargylamines
4.2.5. N-(3,4-Difluorophenyl)-3-amino-3-(2,4-difluorophenyl)-1-
Aldehyde (1 mmol), amine (1.5 mmol), and phenylacetylene
(2 mmol) were mixed with copper chloride (0.3 mmol) and ground
into a fine, homogeneous mixture; then the mixture was put in a
10-mL sealed tube flask and exposed to microwave irradiation at
800 W using a microwave oven for an appropriate time under
nitrogen. After completion of the reaction (as monitored by TLC),
the reaction mixture was diluted with ethyl acetate, the catalyst
was filtered through Celite. After removal of the solvent under
vacuum, the crude material was purified by flash column
chromatography (using hexane:ethyl = 8:1 acetate as elute) to
afford pure product.
phenylprop-1-yne (4cc)
IR (KBr, cmÀ1):
n
3418, 3080, 2926, 2229, 1609, 1521, 1428,
1272, 1219, 965, 851, 757, 691; 1H NMR (500 MHz, CDCl3):
7.66–
7.70 (m, 1H), 7.28–7.42 (m, 5H), 6.85–7.01 (m, 3H), 6.42–6.44 (m,
1H), 5.60 (s, 1H), 4.30 (brs, 1H); 19F NMR (470 MHz, CDCl3):
d
d
À109.3 (s, 1F), À114.0 (q, J = 8 Hz, 1F), À136.7 (t, J = 9 Hz, 1F),
À150.6 (s, 1F); 13C NMR (125 MHz, CDCl3):
d
163.0 (dd, 1J = 249 Hz,
2J = 13 Hz), 160.4 (dd, 1J = 249 Hz, 2J = 13 Hz), 150.7 (dd,
1J = 244 Hz, 2J = 13 Hz), 144.0 (dd, 1J = 238 Hz, 2J = 13 Hz), 143.0
(s), 131.8 (s), 129.8 (q, J = 5 Hz), 128.8 (s), 128.4 (s), 122.6 (dd,
1J = 13 Hz, 2J = 4 Hz), 117.6 (dd, 1J = 23 Hz, 2J = 2 Hz), 111.8 (dd,
1J = 21 Hz, 2J = 4 Hz), 109.6 (q, J = 3 Hz), 104.4 (t, J = 25 Hz), 103.1
(d, J = 21 Hz), 86.5 (s), 85.4 (s), 45.0 (d, J = 4 Hz); EI-MS: m/z (%):
355 (M+, 3), 227 (M+–F2C6H4, 84), 127 (F2C6H3N+, 100); HRMS
cacld. for C21H13NF4: 355.0984. Found: 355.0972.
4.2.1. N-(4-Fluorophenyl)-3-amino-3-(3-fluorophenyl)-1-
phenylprop-1-yne (4ae)
IR (KBr, cmÀ1):
n
3415, 3070, 2869, 2392, 1628, 1583, 1500, 1448,
1261, 1196, 835, 787, 682; 1H NMR (500 MHz, CDCl3):
7.01–7.43
(m, 9H), 6.89–6.93 (m, 2H), 6.67–6.70 (m, 2H), 5.41 (s, 1H), 4.07 (brs,
1H); 19F NMR (470 MHz, CDCl3):
À112.2 to À112.1 (m, 1F), À125.9
(d, J = 3.8 Hz, 1F); 13C NMR (125 MHz, CDCl3):
163.4 (d,
d
4.2.6. N-(3,4-Difluorophenyl)-3-amino-3-(3-fluorophenyl)-1-
d
phenylprop-1-yne (4ac)
d
IR (KBr, cmÀ1):
n
3415, 3062, 2853, 2226, 1609, 1518, 1444,
1216, 755, 689; 1H NMR (500 MHz, CDCl3):
7.28–7.42 (m, 8H),
6.92–7.03 (m, 2H), 6.51–6.55 (m, 1H), 6.37–6.40 (m, 1H), 5.36 (s,
J = 207.5 Hz), 161.4 (d, J = 205 Hz), 158.6 (d, J = 3 Hz), 147.6 (s),
138.5 (d, J = 8 Hz), 131.9 (s), 130.4 (d, J = 8 Hz), 128.7 (s), 128.4 (s),
d

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W.-Q. Du et al. / Journal of Fluorine Chemistry 129 (2008) 695–700
1H), 4.13 (brs, 1H); 19F NMR (470 MHz, CDCl3):
d
À111.9 to À111.8
J = 9.0 Hz, 2H), 7.31–7.44 (m, 5H), 6.68 (d, J = 9.0 Hz, 2H), 6.0 (d,
(m, 1F), À136.8 to À136.7 (m, 1F), À150.9 to À150.8 (m, 1F); 13C
J = 8.5 Hz, 1H), 5.26 (d, J = 8.5 Hz, 1H); 19F NMR (470 MHz, CDCl3):
d
NMR (125 MHz, CDCl3):
d
163.3 (d, J = 246 Hz), 150.8 (dd,
À143.3 (dd, 1J = 21 Hz, 2J = 6 Hz, 2F), À152.5 (t, J = 21 Hz, 1F),
1J = 244 Hz, 2J = 14 Hz), 144.0 (dd, 1J = 236 Hz, 2J = 14 Hz), 143.2
(dd, 1J = 9 Hz, 2J = 3 Hz), 141.7 (d, J = 8 Hz), 131.9 (s), 130.6 (s),
128.8 (s), 128.5 (s), 122.8 (d, J = 3 Hz), 122.3 (s), 117.55 (d,
J = 18 Hz), 115.4 (d, J = 21 Hz), 114.4 (d, J = 22 Hz), 109.7 (dd,
1J = 5 Hz, 2J = 3 Hz), 103.2 (d, J = 21), 87.1 (s), 85.9 (s), 50.7 (d,
J = 1 Hz); EI-MS: m/z (%): 337 (M+, 3), 209 (M+–F2C6H4NH, 100);
HRMS cacld. for C21H14NF3: 337.1078. Found: 337.1073.
À161.0 to À160.1 (m, 2F); 13C NMR (125 MHz, CDCl3):
d 150.3 (s),
145.7–145.9, 143.7–144.2 (dm, J = 253 Hz), 142.3–142.7, 140.4–
140.7 (dm, J = 253 Hz), 139.7 (s), 138.7–139.0, 136.6–137.0 (dm,
J = 250 Hz), 131.9 (s), 129.3 (s), 128.5 (s), 126.3 (s), 121.3 (s), 113.0–
113.3 (m), 112.0 (s), 85.6 (s), 83.3 (s), 40.1 (s); EI-MS: m/z (%):
418 (M+, 3), 281 (M+–NO2C6H4NH, 100); HRMS cacld. for C21H11N2
O2F5: 418.0741. Found: 418.0725.
4.2.7. N-(4-Fluorophenyl)-3-amino-3-(pentafluorophenyl)-1-
4.2.10. N-(3-Chlorophenyl)-3-amino-3-(pentafluorophenyl)-1-
phenylprop-1-yne (4de)
phenylprop-1-yne (4dd)
IR (KBr, cmÀ1):
n
3441, 3043, 2962, 2223, 1506, 1219, 1125, 984,
756, 690; 1H NMR (500 MHz, CDCl3):
7.28–7.53 (m, 6H), 6.67–
6.93 (m, 3H), 5.83 (d, J = 7.5 Hz, 1H), 4.35 (d, J = 8.0 Hz, 1H); 19F
IR (KBr, cmÀ1):
n
3419, 3061, 2926, 2233, 1596, 1501, 1121, 992,
d
757, 686; 1H NMR (500 MHz, CDCl3):
d
7.08–7.51 (m, 7H), 6.56–
6.76 (m, 2H), 5.87 (d, J = 6.0 Hz, 1H), 4.55 (d, J = 5.0 Hz, 1H); 19F
NMR (470 MHz, CDCl3): À143.6 (dd, 1J = 22 Hz, 2J = 7 Hz, 2F),
À153.6 (t, J = 21 Hz, 1F), À160.8 to À160.6 (m, 2F); 13C NMR
NMR (470 MHz, CDCl3):
d
À124.5 to À124.6 (m, 1F), À143.7 (dd,
1J = 22 Hz, 2J = 8 Hz, 2F), À153.8 (t, J = 21 Hz, 1F), À160.8 to À160.9
(m, 2F); 13C NMR (125 MHz, CDCl3):
d
157.2 (d, J = 238 Hz), 145.8–
(125 MHz, CDCl3): d 146.1 (s), 145.8–146.1, 143.7–144.0 (dm,
145.9, 143.8–144.0 (dm, J = 245 Hz), 142.0–142.1, 140.0–140.2
(dm, J = 251Hz), 141.2 (d, J = 1 Hz), 138.6–138.9, 136.6–136.9 (dm,
J = 252 Hz), 131.9 (s), 129.0 (s), 128.4 (s), 121.8 (s), 116.1 (d,
J = 22Hz), 115.6 (d, J = 8 Hz), 114.0–114.2 (m), 84.8 (s), 84.8 (s),
41.8 (s); EI-MS: m/z (%): 391 (M+, 9), 281 (M+–FC6H4NH, 100);
HRMS cacld. for C21H11NF6: 391.0794. Found: 391.0796.
J = 263 Hz), 142.1–143.4, 140.0–140.3 (dm, J = 256 Hz), 138.6–
139.0, 136.6–137.0 (dm, J = 256 Hz), 135.3 (s), 131.9 (s), 129.1 (s),
128.4 (s), 121.7 (s), 120.9 (s), 119.6 (s), 113.9 (s), 111.8 (s), 110.9–
111.1 (m), 85.0 (s), 84.4 (s), 40.7 (s); EI-MS: m/z (%): 407 (M+, 6),
281 (M+–ClC6H4NH, 100); HRMS cacld. for C21H11NF5Cl: 407.0500.
Found: 407.0493.
Crystal data for 3 g C21H11NF6 (CCDC 669044): Mw = 391.31,
˚
˚
monoclinic, space group P2(1)/n, a = 12.379(1) A, b = 5.960(2) A,
c = 24.17(2) A, beta = 101.869(14)8, V = 1745(3) A3, Z = 4, Dc =
Acknowledgment
˚
1.489 mg/m3, F(0 0 0) = 792, crystal size 0.30 mm  0.20 mm Â
0.10 mm, Theta range for data collection 2.78–25.048, limiting
indices À14 ꢀ h ꢀ 14, À7 ꢀ k ꢀ 7, À28 ꢀ l ꢀ 20, Reflections col-
lected/unique 8299/3065 [R(int) = 0.0525], completeness to
theta = 25.04, 99.3%, max. and min. transmission 0.9869 and
0.9614, refinement method full-matrix least-squares on F2, data/
restraints/parameters = 3065/0/254, goodness-of-fit on F2 = 0.998,
final R indices [I > 2sigma(I)] R1 = 0.0876, wR2 = 0.2624, R indices
(all data) R1 = 0.1373, wR2 = 0.3121, extinction coefficient =
This work was supported by the National Science Foundation of
China (No. 20772078).
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