FeCl3·6H2O-mediated reaction of [60]fullerene with amidoximes

Article abstract of DOI:10.1016/j.tet.2016.03.070

A FeCl₃·6H₂O-mediated reaction of [60]fullerene with amidoximes for the preparation of fulleroimidazolines has been presented. This reaction shows a wide substrate scope, and the products obtained from alkyl-substituted amidoximes ar

Full text of DOI:10.1016/j.tet.2016.03.070

Tetrahedron 72 (2016) 2476e2480
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FeCl3$6H2O-mediated reaction of [60]fullerene with amidoximes
,
b
,
a
a
a
a
Fang Fang a, Jianmin Zhang a , Lei Cao , Subo Shen , Yuwei Guo , Zhiqing He ,
*
Han Hu a
a Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, PR China
b Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai
200032, PR China
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 7 January 2016
Received in revised form 17 March 2016
Accepted 22 March 2016
Available online 23 March 2016
A
FeCl3$6H2O-mediated reaction of [60]fullerene with amidoximes for the preparation of full-
eroimidazolines has been presented. This reaction shows a wide substrate scope, and the products ob-
tained from alkyl-substituted amidoximes are first disclosed. In addition, a possible mechanism is
proposed.
Ó 2016 Elsevier Ltd. All rights reserved.
Keywords:
Fullerene
Amidoximes
FeCl3$6H2O
Fulleroimidazolines
1,3-Dipolar cycloaddition
1. Introduction
arylbenzamidines,9 coincidently, Yang’s group reported the re-
action using CuI/Phen (1,10-phenanthroline) instead of Ag2CO3.10a
Amidoximes possess good coordination with metal, which can
be used for synthesis of various complexes,1 or as selective
extracting reagents for toxic metal cations.2 It is well known that
amidoximes are favorable building blocks for the preparation of all
kinds of organic heteroatom compounds, such as imidazoles,3
benzimidazoles,4 oxadiazoles,5 and triazoles.6 However, there are
few reports about the synthesis of imidazolines through the re-
action of amidoximes with electron-deficient alkenes or alkynes.
Based on our experience in the synthesis of fullerene heterocyclic
derivatives,7 we reckon that fullerene who possess special electron-
deficient olefins may react with amidoximes to construct [60]
fullerene-fused imidazolines, which by the way would also be in
favor of the search for new reaction of electron deficient alkenes or
alkynes to imidazolines.
On account of the potential applications of C60 derivatives in
material science and biological chemistry,8 the efficient method-
ologies for their synthesis have strongly attracted lots of re-
searchers’ attention. Recently, an interesting topic is the synthesis
of the [60]fullerene-fused imidazolines, when Wang’s group firstly
reported the synthesis of the [60]fullerene-fused imidazolines via
silver carbonate promoted reaction of C60 with N-
Currently, they also described 4-dimethylaminopyridine (DMAP)-
catalyzed reaction of N-tosylaziridinofullerenes with amidines for
the preparation of fulleroimidazole derivatives.10b However, ami-
dines bearing alkyl group cannot afford the corresponding products
with these methods.10 By now, the reported fulleroimidazolines are
synthesized using amidines as starting materials. Therefore, it is
still significant and challenging to achieve various fulleroimidazole
derivatives.
On the other hand, transition-metal-catalyzed or -mediated
approaches become increasingly popular in the field of organic
synthesis, including iron which is the second highest metal element
in the crust. It is prevalent with the feature of cheap, easily avail-
able, nontoxic and effective catalyst for numerous organic reactions
in catalytic area.11 Bearing these in mind, we set out to explore the
possibilities and fortunately we found that FeCl3$6H2O could suc-
cessfully promote the reaction of amidoximes with C60
.
Herein, we report a FeCl3$6H2O-mediated cycloaddition re-
action of C60 with amidoximes to provide fulleroimidazole de-
rivatives with a broad substrate scope.
2. Results and discussion
When we found that the reaction of C60 with N-phenyl-
benzamidoxime 2a in the presence of FeCl3$6H2O in a molar ratio of
* Corresponding author. Tel./fax: þ86 21 66133801; e-mail address: jmzhang@
shu.edu.cn (J. Zhang).
http://dx.doi.org/10.1016/j.tet.2016.03.070
0040-4020/Ó 2016 Elsevier Ltd. All rights reserved.

F. Fang et al. / Tetrahedron 72 (2016) 2476e2480
2477
1:5:1 at 130 ꢀC under air atmosphere for 10 h afforded the desired
Table 2
Substrate scope of FeCl3$6H2O-mediated reaction of C60 with amidoximesa
product 3a in 13% yield (Table 1, entry 1), we used this as model
reaction and moved ahead to pursue optimized reaction conditions
by varying the use of additives, bases, their molar ratio and reaction
temperatures (Table 1). And finally, a molar ratio of C60, 2a,
FeCl3$6H2O, and DMAP as 1:5:1:2 and a temperature of 130 ꢀC in
1,2-dichlorobenzene (o-DCB) turned out as the best optimized re-
action conditions (Table 1, entry 11). It is worth noting that there is
no reaction in the absence of FeCl3$6H2O (Table 1, entry 14).
Armed with the above optimized reaction conditions, we step
forward to investigate the scope of the FeCl3$6H2O-mediated cy-
cloaddition reaction of C60 with various amidoximes, and the re-
sults are presented in Table 2. Both electron-donating and electron-
withdrawing groups were applied to test the applicability of this
methodology, and it was found that the vast majority of the ami-
doximes could successfully complete the transformation and give
the desired [60]fullereoimidazolines with 15e40% isolated yields.
When the substituent group on the para position of R2 phenyl ring
is methyl or fluorine, the substituent group on the R1 phenyl ring
has little or no significant influence on the reaction (Table 2, entries
3, 7, 13, entries 9, 14), except 2k bearing a nitro group afforded 3k
with somehow lower isolated yield (Table 2, entry 11). An electron-
donating group on the R2 aromatic ring gave a slightly higher yield
than electron-withdrawing group when amidoximes carrying the
same R1 aromatic ring (Table 2, entries 7, 9e14). Additionally, with
the increasing of the steric hindrance on substituted group R2, the
yields tended to decline such as 3c and 3b dropping from 35% to
20%, 3g and 3e from 33% to 0 (Table 2, entries 2, 3, 5e7). Here
unfortunately the ortho-substitute on R2 phenyl ring inhibited the
cycloaddition reaction. Luckily, the present method was also
Entry
R1
R2
Product
Yield (%)b
1
2
3
4
5
6
7
8
Ph
Ph
Ph
Ph
3a
3b
3c
3d
3e
3f
3g
3h
3i
3j
3k
3l
3m
3n
3o
3p
40 (96)
20 (72)
35 (82)
33 (79)
0
27 (84)
33 (80)
19 (76)
29 (74)
32 (76)
20 (58)
30 (79)
33 (70)
29 (80)
15 (37)
25 (60)
m-MePh
p-MePh
Ph
o-MePh
m-MePh
p-MePh
m-FPh
p-FPh
p-ClPh
p-MePh
p-OMePh
p-MePh
p-FPh
p-MePh
p-MePh
p-MePh
p-MePh
p-MePh
p-MePh
p-MePh
p-NO2Ph
p-NO2Ph
p-FPh
9
10
11
12
13
14
15
16
p-FPh
2-phenylethyl
p-MePh
p-MePh
Bn
a
Unless otherwise noted, all reactions were carried out with a molar ratio of C60
/
2/FeCl3$6H2O/DMAP¼1:5:1:2 in 7 mL o-DCB at 130 ꢀC for 8e12 h under air.
b
Isolated yield; the values in parentheses were based on consumed C60
.
successfully expanded to the preparation of [60]fullereoimidazo-
lines 3o and 3p, which derived from amidoximes containing an
alkyl group (Table 2, entries 15 and 16).
All of the known compounds were confirmed through in-
terpretation of their spectral data in accordance with those re-
ported in the literatures.9,10 The structures of new C60-fused
imidazole derivatives 3b, 3f, 3h, 3i, 3le3p were fully characterized
by their MALDI-FTICR-MS, 1H NMR, 19F NMR, 13C NMR, FTIR, and
UVevis spectra.
Table 1
Optimization of the reaction conditionsa
In order to get a deeper understanding of the reaction mecha-
nism, a free radical scavenger 2,2,6,6-tetramethylpiperidine-1-oxyl
(TEMPO,
5 equiv) was added to the reaction mixture (see
Supplementary data). The cycloaddition reaction was not hindered,
which indicates that the reaction may not relate to the formation of
an iminyl or nitrogen radical.12
Entry
Additive
Base
Molar ratiob
Yield (%)c
1
2
3
4
5
6
7
8
FeCl3$6H2O
Fe(ClO4)3$6H2O
Ag2CO3
d
1:5:1:0
1:5:1:0
1:5:1:0
1:5:1:0
1:5:1:0
1:5:1:0
1:5:1:0
1:5:1
1:5:1:2
1:5:1:2
1:5:1:2
1:5:1:2
1:5:1:2
1:5:0:2
1:5:1:2
1:5:1:2
1:5:1:2
1:5:0.5:2
1:5:2:2
1:3:1:2
1:8:1:2
1:5:1:1
1:5:1:3
13 (75)
4 (60)
0
Trace
0
Based on the above results and previous literatures on iron-
catalyzed or -mediated reactions,12,13 a plausible mechanism for
the reaction of C60 with amidoximes is proposed and described in
Scheme 1. First, in the presence of FeCl3$6H2O and base, the ami-
doxime 2 gives the intermediate 4 under heating condition, fol-
lowed by the elimination of H2O and Fe(III) to afford dipole 5, which
then partakes in a 1,3-dipolar cycloaddition reaction with C60 to
generate fullereoimidazoline 3.
d
d
CuI
d
Cu(OAc)2$H2O
Mn(OAc)2$4H2O
Mn(OAc)3$2H2O
PhI(OAc)2
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
FeCl3
d
d
0
0
d
d
Trace
7 (42)
18 (70)
40 (96)
Trace
41 (89)
0
17 (65)
39 (83)
35 (82)
21 (76)
38 (84)
23 (94)
35 (81)
29 (91)
40 (94)
9
Na2CO3
Cs2CO3
DMAP
DABCO
DMAP
DMAP
DMAP
DMAP
DMAP
DMAP
DMAP
DMAP
DMAP
DMAP
DMAP
10
11
12
13
14
15d
16e
17f
18
19
20
21
22
23
d
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
FeCl3$6H2O
Scheme 1. Plausible mechanism for the formation of 3.
a
Unless specified, all reactions were performed in 7 mL o-DCB at 130 ꢀC for 10 h
under air.
3. Conclusion
b
c
d
e
f
Molar ratio refers to C60/2a/additive/base.
Isolated yield; the values in parentheses were based on consumed C60
.
In conclusion, a novel and efficient method has been success-
fully developed to establish
a FeCl3$6H2O-mediated 1,3-dipolar cycloaddition reaction of [60]
The reaction was operated at 110 ꢀC.
The reaction was operated at 150 ꢀC.
C60-fused imidazolines via
The reaction was carried out under a N2 atmosphere.

2478
F. Fang et al. / Tetrahedron 72 (2016) 2476e2480
fullerene with various amidoximes. This novel method, which uses
FeCl3$6H2O as the additive, DMAP as the base, services a wide range
of functionalities including aryl and alkyl substituted amidoximes.
To expand the application of amidoximes in organic synthesis, we
are currently planning to synthesize new imidazolines with the
employ of amidoximes and other compounds owning electron-
deficient alkene or alkyne.
2H), 7.11 (d, J¼8.0 Hz, 2H), 6.89 (t, J¼7.7 Hz, 1H), 6.59 (d, J¼7.5 Hz,
2H), 6.34 (d, J¼8.4 Hz, 1H), 2.28 (s, 3H), 2.11 (s, 3H).
2g: White solid (604.3 mg, 50%); mp 141.8e143.8 ꢀC; 1H NMR
(500 MHz, DMSO-d6)
7.12e7.08 (m, 2H), 6.85 (d, J¼8.1 Hz, 2H), 6.58e6.52 (m, 2H), 2.27 (s,
3H), 2.13 (s, 3H); 13C NMR (125 MHz, DMSO-d6)
149.51, 138.84,
138.24, 129.97, 129.59, 128.81, 128.77, 127.65, 120.20, 20.83, 20.16;
UVevis (CHCl3) lmax/nm 246, 269; FTIR
/cmꢁ1 (KBr) 3351, 3214,
d 10.37 (s, 1H), 8.09 (s, 1H), 7.27e7.21 (m, 2H),
d
n
4. Experimental section
4.1. General
2920, 2857, 1609, 1516, 1483, 1391, 1311, 1237, 1181, 1108, 814; HRMS
(EI-TOF, 70 eV) m/z Calcd for C15H16N2O [M]þ 240.1263, Found
240.1260.
2h: White solid (523.7 mg, 43%); mp 139.4e139.7 ꢀC; 1H NMR
Unless otherwise noted, solvents and reagents were purchased
from commercial sources and used without further purification. 1H,
13C NMR and 19F spectra were recorded on a Bruker DRX-500 MHz
spectrometer operating at 500 MHz, 125 MHz and 470 MHz, re-
spectively. The chemical shifts are reported in parts per million
(500 MHz, DMSO-d6)
d
10.74 (s, 1H), 8.57 (s, 1H), 7.33 (d, J¼7.5 Hz,
2H), 7.13 (d, J¼7.9 Hz, 2H), 7.07e6.97 (m, 1H), 6.61e6.41 (m, 3H),
2.27 (s, 3H); 19F NMR (470 MHz, DMSO-d6)
d
ꢁ113.11 (s, 1F); 13C
1
NMR (125 MHz, DMSO-d6)
d
162.24 (d, JCeF¼240.9 Hz), 148.45,
3
3
143.70 (d, JCeF¼10.9 Hz), 138.70, 129.75, 129.73 (d, JCeF¼9.9 Hz),
4
2
(ppm) on the
d
scale. The solvent peak was used as a reference
129.02, 127.51, 115.03 (d, JCeF¼2.3 Hz), 106.57 (d, JCeF¼21.1 Hz),
105.72 (d, 2JCeF¼24.8 Hz), 20.87; UVevis (CHCl3) lmax/nm 250, 268;
value, for 1H NMR: CDCl3¼7.26 ppm, DMSO-d6¼2.50 ppm, for 13C
NMR: CDCl3¼77.16 ppm, DMSO-d6¼39.52 ppm. 19F NMR chemical
FTIR n
/cmꢁ1 (KBr) 3391, 3159, 2946, 2857, 1605, 1508, 1492, 1446,
shifts were determined relative to CFCl3 at
d
0.0. HRMS (high res-
1380, 1313, 1256, 1174, 1151, 1112, 823, 767, 684; HRMS (EI-TOF,
70 eV) m/z Calcd for C14H13N2OF [M]þ 244.1012, Found 244.1013.
2i: White solid (632.4 mg, 52%); mp 129.6e130.3 ꢀC; 1H NMR
olution mass spectra) was obtained on Waters Micromass GCT or
Thermo Fisher Scientific LTQ FT Ultra instrument by Shanghai Mass
Spectrometry Center, Shanghai Institute of Organic Chemistry.
(500 MHz, DMSO-d6)
d
10.45 (s, 1H), 8.28 (s, 1H), 7.24 (d, J¼7.6 Hz,
2H), 7.12 (d, J¼7.9 Hz, 2H), 6.90 (t, J¼8.8 Hz, 2H), 6.73e6.58 (m, 2H),
4.2. General procedure for the preparation of amidoximes4b,5f
2.27 (s, 3H); 19F NMR (470 MHz, DMSO-d6)
d
ꢁ123.22 (s, 1F); 13C
1
NMR (125 MHz, DMSO-d6)
d
156.97 (d, JCeF¼237.2 Hz), 149.30,
4
Chlorooxime was prepared from aldehyde in two steps. Then, to
the chlorooxime (5 mmol) in DMF (7 mL) was added the corre-
sponding amine (10 mmol) at 0 ꢀC. The solution was stirred at room
temperature until TLC shows the complete disappearance of the
chlorooxime. The solution was diluted with EtOAc, washed with
H2O, saturated aqueous NaCl solution, dried over anhydrous MgSO4
and evaporated under reduced pressure. The residue was purified
by flash column chromatography on silica gel (EtOAc/petroleum
ether) to give the corresponding N-substituted amidoxime 2.
2a:4b White solid (445.8 mg, 42%); mp 136.1e137.1 ꢀC; 1H NMR
138.41, 137.91 (d, JCeF¼2.2 Hz), 129.73, 128.87, 127.70, 121.57 (d,
3JCeF¼7.9 Hz), 114.88 (d, JCeF¼22.4 Hz), 20.84; UVevis (CHCl3)
2
lmax/nm 247, 268; FTIR n
/cmꢁ1 (KBr) 3362, 3076, 2945, 2818, 1625,
1511, 1431, 1386, 1298, 1218, 1155, 1111, 823; HRMS (EI-TOF,
70 eV) m/z Calcd for C14H13N2OF [M]þ 244.1012, Found 244.1009.
2j:15 White solid (741.7 mg, 57%); mp 172.3e173.8 ꢀC; 1H NMR
(500 MHz, DMSO-d6)
d
10.58 (s, 1H), 8.45 (s, 1H), 7.26 (d, J¼7.9 Hz,
2H), 7.13 (d, J¼7.9 Hz, 2H), 7.09 (d, J¼8.8 Hz, 2H), 6.64 (d, J¼8.6 Hz,
2H), 2.28 (s, 3H).
2k:16 Yellow solid (689.5 mg, 51%); mp 193.0e194.9 ꢀC; 1H NMR
(500 MHz, DMSO-d6)
d
10.56 (s, 1H), 8.30 (s, 1H), 7.39e7.30 (m, 5H),
(500 MHz, DMSO-d6)
d
10.96 (s, 1H), 8.42 (s, 1H), 8.16 (d, J¼8.9 Hz,
7.04 (t, J¼7.9 Hz, 2H), 6.77 (t, J¼7.3 Hz, 1H), 6.64 (d, J¼8.0 Hz, 2H).
2H), 7.60 (d, J¼8.8 Hz, 2H), 6.89 (d, J¼8.2 Hz, 2H), 6.57 (d, J¼8.3 Hz,
2b: White solid (427.2 mg, 38%); mp 133.2e133.7 ꢀC; 1H NMR
2H), 2.14 (s, 3H).
(500 MHz, DMSO-d6)
d
10.54 (s, 1H), 8.19 (s, 1H), 7.40e7.29 (m, 5H),
2l: Yellow solid (628.1 mg, 44%); mp 172.6e173.8 ꢀC; 1H NMR
6.90 (t, J¼7.7 Hz, 1H), 6.59 (d, J¼7.5 Hz, 1H), 6.56 (s, 1H), 6.36 (d,
(500 MHz, DMSO-d6)
2H), 7.59 (d, J¼8.3 Hz, 2H), 6.69 (d, J¼9.0 Hz, 2H), 6.64 (d, J¼8.9 Hz,
2H), 3.62 (s, 3H); 13C NMR (125 MHz, DMSO-d6)
154.54, 148.74,
147.36, 139.61, 133.97, 129.01, 123.41, 122.63, 113.96, 55.11; UVevis
(CHCl3) lmax/nm 252, 290; FTIR
/cmꢁ1 (KBr) 3344, 3246, 2955,
d
10.83 (s, 1H), 8.31 (s, 1H), 8.15 (d, J¼8.8 Hz,
J¼8.0 Hz, 1H), 2.10 (s, 3H); 13C NMR (125 MHz, DMSO-d6)
d 149.33,
141.32, 137.53, 132.94, 128.91, 128.23, 128.12, 127.69, 121.51, 120.41,
d
117.02, 21.09; UVevis (CHCl3) lmax/nm 247, 269; FTIR n
/cmꢁ1 (KBr)
3400, 3058, 2921, 2814,1627, 1603, 1499,1391, 1293, 1176,1119, 844,
771, 733, 701; HRMS (EI-TOF, 70 eV) m/z Calcd for C14H14N2O [M]þ
226.1106, Found 226.1104.
n
2835, 1637, 1597, 1516, 1467, 1393, 1344, 1291, 1246,1176, 1108, 1035,
858, 832, 747; HRMS (EI-TOF, 70 eV) m/z Calcd for C14H13N3O4 [M]þ
287.0906, Found 287.0912.
2c:14 White solid (508.0 mg, 45%); mp 152.3e154.2 ꢀC; 1H NMR
(500 MHz, DMSO-d6)
d
10.50 (s, 1H), 8.22 (s, 1H), 7.40e7.26 (m, 5H),
2m: White solid (476.8 mg, 39%); mp 143.4e144.9 ꢀC; 1H NMR
6.85 (d, J¼8.1 Hz, 2H), 6.56 (d, J¼8.2 Hz, 2H), 2.13 (s, 3H).
(500 MHz, DMSO-d6)
d
10.48 (d, J¼1.9 Hz, 1H), 8.20 (s, 1H),
2d:5f White solid (483.1 mg, 43%); mp 125.3e125.9 ꢀC; 1H NMR
7.41e7.33 (m, 2H), 7.19e7.10 (m, 2H), 6.87 (d, J¼8.3 Hz, 2H), 6.55 (d,
(500 MHz, DMSO-d6)
d
10.49 (s, 1H), 8.24 (s, 1H), 7.26 (d, J¼8.0 Hz,
J¼8.0 Hz, 2H), 2.14 (s, 3H); 19F NMR (470 MHz, DMSO-d6)
ꢁ112.53
d
2H), 7.12 (d, J¼7.9 Hz, 2H), 7.04 (t, J¼7.8 Hz, 2H), 6.76 (t, J¼7.3 Hz,
1H), 6.65 (d, J¼7.8 Hz, 2H), 2.28 (s, 3H).
(s, 1F); 13C NMR (125 MHz, DMSO-d6)
d
162.35 (d, 1JCeF¼245.8 Hz),
3
148.80, 138.64, 129.94 (d, JCeF¼8.4 Hz), 129.93, 129.29 (d,
2e: White solid (434.5 mg, 36%); mp 193.4e193.9 ꢀC; 1H NMR
4JCeF¼3.0 Hz), 128.94, 120.46, 115.21 (d, JCeF¼21.7 Hz), 20.21;
2
(500 MHz, DMSO-d6)
d
8.92 (s, 1H), 7.87 (s, 1H), 7.85 (s, 1H), 7.35 (d,
UVevis (CHCl3) lmax/nm 242, 270; FTIR n
/cmꢁ1 (KBr) 3386, 3072,
J¼8.3 Hz, 2H), 7.19e7.11 (m, 2H), 7.09 (d, J¼8.2 Hz, 2H), 6.93 (t,
2934, 2794, 1631, 1608, 1516, 1386, 1311, 1223, 1158, 1119, 841, 812;
HRMS (EI-TOF, 70 eV) m/z Calcd for C14H13N2OF [M]þ 244.1012,
Found 244.1018.
J¼7.3 Hz, 1H), 2.24 (s, 6H); 13C NMR (125 MHz, DMSO-d6)
d 153.16,
137.99, 137.78, 130.96, 130.63, 129.68, 127.78, 126.61, 122.97, 121.36,
118.57, 20.80, 18.36; UVevis (CHCl3) lmax/nm 249; FTIR
n
/cmꢁ1
2n: White solid (449.3 mg, 36%); mp 153.1e153.7 ꢀC; 1H NMR
(KBr) 3295, 3030, 2919, 2861, 1641, 1596, 1555, 1517, 1454, 1408,
(500 MHz, DMSO-d6) d 10.56 (s, 1H), 8.38 (s, 1H), 7.42e7.35 (m, 2H),
1298, 1242, 1115, 1048, 825, 743; HRMS (EI-TOF, 70 eV) m/z Calcd for
7.15 (t, J¼8.9 Hz, 2H), 6.95e6.88 (m, 2H), 6.70e6.62 (m, 2H); 19F
C
15H16N2O [M]þ 240.1263, Found 240.1259.
NMR (470 MHz, DMSO-d6)
NMR (125 MHz, DMSO-d6)
d
ꢁ112.40 (s, 1F), ꢁ122.99 (s, 1F); 13C
2f:15 White solid (565.9 mg, 47%); mp 77.7e79.5 ꢀC; 1H NMR
d
162.39 (d, 1JCeF¼246.0 Hz), 157.12 (d,
4
(500 MHz, DMSO-d6)
d
10.48 (s, 1H), 8.12 (s, 1H), 7.27 (d, J¼8.1 Hz,
1JCeF¼237.6 Hz), 148.53, 137.69 (d, JCeF¼2.3 Hz), 129.98 (d,

F. Fang et al. / Tetrahedron 72 (2016) 2476e2480
2479
4
3
3JCeF¼8.5 Hz), 129.04 (d, JCeF¼3.0 Hz), 121.83 (d, JCeF¼7.9 Hz),
145.00,144.97,144.90,144.54,144.53,143.95, 142.71,142.59,142.43,
142.28, 142.19, 142.17, 141.96, 141.92, 141.55, 140.73, 140.62, 140.35,
139.40, 139.25, 136.91,135.49, 130.03, 129.82, 129.40, 128.87, 128.46,
126.84, 126.57, 93.49 (sp3-C of C60), 86.58 (sp3-C of C60), 21.65,
115.28 (d, 2JCeF¼21.7 Hz), 114.98 (d, 2JCeF¼22.4 Hz); UVevis (CHCl3)
lmax/nm 241, 268; FTIR n
/cmꢁ1 (KBr) 3352, 3074, 2944, 2828, 1634,
1617, 1511, 1387, 1299, 1223, 1158, 1120, 840; HRMS (EI-TOF,
70 eV) m/z Calcd for C13H10N2OF2 [M]þ 248.0761, Found 248.0762.
2o: Yellow solid (696.5 mg, 55%; inseparable E/Z mixture, E/Z not
determined, major:minor¼2:1); mp 80.4e82.1 ꢀC; 1H NMR
21.49; UVevis (CHCl3) lmax/nm 256, 316, 428, 536, 691; FTIR n
/cmꢁ1
(KBr) 2914, 2851, 1590, 1553, 1504, 1428, 1362, 1294, 1178, 1139,
1099, 1020, 824, 767, 748, 697, 562, 522; MALDI-FTICR MS m/z Calcd
for C75H15N2 [MþH]þ 943.1230, Found 943.1218.
(500 MHz, DMSO-d6)
d
9.58 (s, 1H), 9.17 (s, 1Hꢂ0.5), 7.95 (s,
1Hꢂ0.5), 7.70 (s, 1H), 7.45e7.41 (m, 2Hꢂ0.5), 7.31e7.27 (m, 2H),
7.24e7.19 (m, 5Hꢂ0.5), 7.13 (t, J¼7.3 Hz, 2Hꢂ0.5), 7.09 (d, J¼8.1 Hz,
2H), 7.06e7.03 (m, 2H), 7.03e6.97 (m, 3H), 2.92e2.86 (m, 2Hꢂ0.5),
2.70e2.63 (m, 2Hꢂ0.5), 2.63e2.56 (m, 2H), 2.55e2.50 (m, 2H), 2.25
3g:10a Black solid (15.5 mg, 33%); 1H NMR (500 MHz, CDCl3/CS2)
d
7.85e7.80 (m, 2H), 7.50e7.44 (m, 2H), 7.20 (t, J¼8.5 Hz, 4H), 2.44
(s, 3H), 2.37 (s, 3H).
3h: Black solid (9.1 mg,19%); 1H NMR (500 MHz, CDCl3/CS2)
d 7.83
(s, 3H), 2.20 (s, 3Hꢂ0.5); 13C NMR (125 MHz, DMSO-d6)
d
major:
(d, J¼8.0 Hz, 2H), 7.43e7.35 (m, 2H), 7.31 (d, J¼9.3 Hz, 1H), 7.24 (d,
149.56, 141.26, 137.57, 129.30, 128.25, 128.18, 125.95, 123.32, 117.66,
31.75, 30.99, 20.38; minor: 154.81, 141.50, 139.71, 132.18, 128.74,
128.32, 128.15, 125.86, 119.13, 32.08, 29.97, 20.31; UVevis (CHCl3)
J¼7.9 Hz, 2H), 7.08e6.99 (m, 1H), 2.46 (s, 3H); 19F NMR (470 MHz,
CDCl3/CS2)
d
ꢁ108.21 (s, 1F); 13C NMR (125 MHz, CDCl3/CS2)
d 163.18
1
(C]N), 162.76 (d, JCeF¼250.9 Hz), 148.71, 147.79, 147.56, 146.12,
146.00, 145.85, 145.80, 145.77, 145.60, 145.58, 145.42, 144.99, 144.89,
144.74,144.52,144.16,143.91,142.70,142.60,142.58 (d, 3JCeF¼9.3 Hz),
142.43, 142.27, 142.12, 142.06, 141.93, 141.89, 141.57, 140.93, 140.37,
139.30,137.02,135.39,130.53 (d, 3JCeF¼9.0 Hz),129.74,129.01,126.47,
lmax/nm 251; FTIR n
/cmꢁ1 (KBr) 3358, 3223, 2911, 2863, 1650, 1607,
1510, 1446, 1395, 1299, 1231, 1114, 812, 732, 700; MALDI-FTICR MS
m/z Calcd for C16H19N2O [MþH]þ 255.1492, Found 255.1492.
2p:4b White solid (421.4 mg, 35%); mp 150.6e152.8 ꢀC; 1H NMR
4
2
(500 MHz, DMSO-d6)
d
9.83 (s, 1H), 7.26 (t, J¼8.0 Hz, 4H), 7.21e7.10
125.04 (d, JCeF¼3.2 Hz), 116.63 (d, JCeF¼21.8 Hz), 114.59 (d,
2JCeF¼20.8 Hz), 93.71 (sp3-C of C60), 86.21 (sp3-C of C60), 21.66;
(m, 5H), 6.25 (t, J¼7.0 Hz, 1H), 4.16 (d, J¼7.0 Hz, 2H), 2.29 (s, 3H).
UVevis (CHCl3) lmax/nm 257, 316, 428, 538, 691; FTIR n
/cmꢁ1 (KBr)
4.3. General procedure for the FeCl3$6H2O-mediated reaction
of C60 with 2aep
2919, 2843, 1589, 1480, 1431, 1357, 1295, 1265, 1180, 1137, 1107, 1011,
865, 823, 769, 689, 567, 522; MALDI-FTICR MS m/z Calcd for
C
74H12N2F [MþH]þ 947.0979, Found 947.0960.
A
mixture of C60 (36.0 mg, 0.05 mmol), amidoximes
3i: Black solid (13.8 mg, 29%); 1H NMR (500 MHz, CDCl3/CS2)
7.81 (d, J¼8.1 Hz, 2H), 7.62e7.54 (m, 2H), 7.23 (d, J¼8.0 Hz, 2H),
(0.25 mmol), FeCl3$6H2O (13.5 mg, 0.05 mmol) and DMAP (12.2 mg,
0.10 mmol) were dissolved in 7 mL o-DCB. Then, the solution was
stirred in one-pot at 130 ꢀC for 8e12 h. After evaporation under
reduced pressure, the residue was directly separated on a silica gel
column with CS2/toluene as the eluent, the desired product 3 was
d
7.14e7.07 (m, 2H), 2.46 (s, 3H); 19F NMR (470 MHz, CDCl3/CS2)
d
ꢁ110.67 (s, 1F); 13C NMR (125 MHz, CDCl3/CS2)
d 163.84 (C]N),
1
161.64 (d, JCeF¼249.8 Hz), 148.89, 147.96, 147.73, 146.28, 146.16,
146.00, 145.96, 145.89, 145.79, 145.74, 145.60, 145.14, 145.05, 144.89,
144.67, 144.31, 144.06, 142.86, 142.75, 142.58, 142.41, 142.28, 142.24,
142.09, 142.02, 141.70, 141.07, 140.50, 139.47, 137.13, 136.84 (d,
4JCeF¼3.1 Hz),135.60,131.31 (d, 3JCeF¼8.5 Hz),129.87,129.13,126.57,
116.67 (d, 4JCeF¼22.6 Hz), 93.53 (sp3-C of C60), 86.63 (sp3-C of C60),
obtained along with unreacted C60
.
3a:9 Black solid (18.4 mg, 40%); 1H NMR (500 MHz, CDCl3/CS2)
7.95 (d, J¼7.3 Hz, 2H), 7.61 (d, J¼7.5 Hz, 2H), 7.49 (t, J¼7.4 Hz, 1H),
d
7.45e7.38 (m, 4H), 7.33 (t, J¼7.4 Hz, 1H); 13C NMR (125 MHz, CDCl3/
CS2)
d
164.34 (C]N), 148.90, 148.04, 147.82, 146.35, 146.25, 146.07,
21.67; UVevis (CHCl3) lmax/nm 257, 317, 429, 538, 692; FTIR n
/cmꢁ1
146.04, 145.95, 145.89, 145.86, 145.69, 145.21, 145.14, 144.73, 144.46,
144.16, 142.92, 142.81, 142.64, 142.48, 142.35, 142.18, 142.13, 141.76,
140.62, 140.57, 139.50, 137.72, 137.14, 135.80, 130.82, 129.93, 129.81,
129.68, 129.06, 128.41, 128.27, 127.94, 93.59 (sp3-C of C60), 86.81
(sp3-C of C60); MALDI-FTICR MS m/z Calcd for C73H11N2 [MþH]þ
915.0917, Found 915.0948.
(KBr) 2918, 2846, 1611, 1556, 1506, 1426, 1365, 1291, 1220, 1181,
1150, 1091, 1006, 823, 576, 526; MALDI-FTICR MS m/z Calcd for
C
74H12N2F [MþH]þ 947.0979, Found 947.0977.
3j:10a Black solid (15.3 mg, 32%); 1H NMR (500 MHz, CDCl3/CS2)
7.81 (d, J¼8.0 Hz, 2H), 7.55 (d, J¼8.6 Hz, 2H), 7.37 (d, J¼8.6 Hz, 2H),
d
7.25 (d, J¼8.0 Hz, 2H), 2.47 (s, 3H).
3b: Black solid (9.3 mg, 20%); 1H NMR (500 MHz, CDCl3/CS2)
3k:10a Black solid (9.6 mg, 20%); 1H NMR (500 MHz, CDCl3/CS2)
d
7.97e7.92 (m, 2H), 7.50e7.46 (m, 1H), 7.44e7.37 (m, 4H), 7.28 (t,
d
8.29 (d, J¼8.2 Hz, 2H), 8.18 (d, J¼8.3 Hz, 2H), 7.48 (d, J¼7.9 Hz, 2H),
J¼7.7 Hz, 1H), 7.12 (d, J¼7.6 Hz, 1H), 2.35 (s, 3H); 13C NMR (125 MHz,
7.23 (d, J¼7.8 Hz, 2H), 2.38 (s, 3H).
CDCl3/CS2)
d
163.95 (C]N), 148.91, 147.91, 147.69, 146.23, 146.12,
3l: Black solid (14.9 mg, 30%); 1H NMR (500 MHz, CDCl3/CS2)
145.95, 145.91, 145.83, 145.80, 145.76, 145.56, 145.08, 145.01, 144.63,
144.45, 144.05, 142.81, 142.70, 142.53, 142.38, 142.26, 142.07, 142.02,
141.65, 140.52, 140.46, 139.58, 139.38, 137.00, 135.63, 130.61, 130.10,
129.84, 129.50, 128.66, 128.25, 126.62, 93.53 (sp3-C of C60), 86.70
(sp3-C of C60), 21.51; UVevis (CHCl3) lmax/nm 256, 316, 429, 536,
d
8.30e8.25 (m, 2H), 8.20e8.14 (m, 2H), 7.53e7.47 (m, 2H),
6.95e6.89 (m, 2H), 3.81 (s, 3H); 13C NMR (125 MHz, CDCl3/CS2)
161.88 (C]N), 159.19, 148.71, 148.25, 147.86, 147.65, 146.19, 146.09,
d
145.92, 145.89, 145.84, 145.58, 145.56, 145.05, 144.99, 144.88,
144.53, 143.97, 143.82, 142.78, 142.69, 142.52, 142.31, 142.14, 142.12,
142.00, 141.94, 141.62, 140.46, 139.47, 136.82, 135.74, 135.56, 132.25,
130.76, 130.53, 123.20, 115.13, 93.31 (sp3-C of C60), 86.92 (sp3-C of
692; FTIR n
/cmꢁ1 (KBr) 2919, 2849, 1595, 1568, 1489, 1445, 1428,
1365, 1297, 1180, 1143, 1023, 778, 762, 727, 693, 561, 526; MALDI-
FTICR MS m/z Calcd for C74H13N2 [MþH]þ 929.1073, Found 929.1060.
3c:9 Black solid (16.1 mg, 35%); 1H NMR (500 MHz, CDCl3/CS2)
C
60), 55.04; UVevis (CHCl3) lmax/nm 256, 316, 428, 539, 691; FTIR n/
cmꢁ1 (KBr) 2920, 2851, 1574, 1507, 1424, 1373, 1337, 1294, 1243,
1174, 1099, 1026, 1000, 852, 798, 759, 576, 520; MALDI-FTICR MS m/
z Calcd for C74H12O3N3 [MþH]þ 990.0873, Found 990.0876.
3m: Black solid (15.6 mg, 33%); 1H NMR (500 MHz, CDCl3/CS2)
d
7.96 (d, J¼7.2 Hz, 2H), 7.48 (d, J¼8.3 Hz, 3H), 7.43 (t, J¼7.5 Hz, 2H),
7.20 (d, J¼8.3 Hz, 2H), 2.36 (s, 3H).
3d:10a Black solid (15.2 mg, 33%); 1H NMR (500 MHz, CDCl3/CS2)
d
7.82 (d, J¼8.1 Hz, 2H), 7.64e7.55 (m, 2H), 7.44e7.37 (m, 2H), 7.31
d
7.99e7.93 (m, 2H), 7.47 (d, J¼8.2 Hz, 2H), 7.23e7.19 (m, 2H),
(t, J¼7.4 Hz, 1H), 7.20 (d, J¼7.9 Hz, 2H), 2.44 (s, 3H).
7.12e7.07 (m, 2H), 2.39 (s, 3H); 19F NMR (470 MHz, CDCl3/CS2)
3f: Black solid (12.8 mg, 27%); 1H NMR (500 MHz, CDCl3/CS2)
d
ꢁ106.96 (s, 1F); 13C NMR (125 MHz, CDCl3/CS2)
d 163.97 (d,
d
7.78 (d, J¼8.1 Hz, 2H), 7.36 (d, J¼7.7 Hz, 2H), 7.24 (d, J¼7.9 Hz, 1H),
7.17 (d, J¼7.9 Hz, 2H), 7.08 (d, J¼7.7 Hz, 1H), 2.41 (s, 3H), 2.32 (s, 3H);
13C NMR (125 MHz, CDCl3/CS2)
163.66 (C]N), 148.99, 147.80,
147.58, 146.12, 146.00, 145.84, 145.80, 145.73, 145.71, 145.67, 145.43,
1JCeF¼252.5 Hz), 162.97 (C]N), 148.80, 147.91, 147.69, 146.22,
146.12, 145.95, 145.91, 145.83, 145.73, 145.72, 145.56, 145.08, 145.06,
145.01, 144.61, 144.37, 144.04, 142.81, 142.70, 142.53, 142.36, 142.23,
142.22, 142.05, 142.00, 141.65, 140.45, 139.39, 137.94, 137.85, 136.96,
d

2480
F. Fang et al. / Tetrahedron 72 (2016) 2476e2480
3
135.62, 132.05 (d, JCeF¼8.5 Hz), 130.52, 129.34, 125.84 (d,
4JCeF¼3.2 Hz), 115.36 (d, 2JCeF¼21.7 Hz), 93.33 (sp3-C of C60), 86.81
(sp3-C of C60), 21.35; UVevis (CHCl3) lmax/nm 257, 316, 428, 538,
Supplementary data
Supplementary data related to this article can be found at http://
dx.doi.org/10.1016/j.tet.2016.03.070.
691; FTIR n
/cmꢁ1 (KBr) 2913, 2856, 1603, 1568, 1503, 1414, 1364,
1281, 1227, 1180, 1147, 1100, 1005, 836, 577, 519; MALDI-FTICR MS
m/z Calcd for C74H12N2F [MþH]þ 947.0979, Found 947.0978.
3n: Black solid (13.8 mg, 29%); 1H NMR (500 MHz, CDCl3/CS2)
References and notes
d
7.99e7.93 (m, 2H), 7.65e7.55 (m, 2H), 7.16e7.09 (m, 4H); 19F NMR
1. (a) Bovenzi, B. A.; Pearse, G. A. J. Chem. Soc., Dalton Trans. 1997, 2793e2797; (b)
ꢁ106.63 (s, 1F), ꢁ110.34 (s, 1F); 13C NMR
ꢀ
ꢀ
Abellan-Lopez, A.; Chicote, M. T.; Bautista, D.; Vicente, J. Dalton Trans. 2014, 43,
592e598.
(470 MHz, CDCl3/CS2)
(125 MHz, CDCl3/CS2)
d
d
164.16 (d, 1JCeF¼253.1 Hz), 162.99 (C]N),
2. (a) Katritzky, A. R.; Huang, L.; Chahar, M.; Sakhuja, R.; Hall, C. D. Chem. Rev.
2012, 112, 1633e1649; (b) Barber, P. S.; Kelley, S. P.; Rogers, R. D. RSC Adv. 2012,
2, 8526e8530; (c) Barber, P. S.; Kelley, S. P.; Griggs, C. S.; Wallace, S.; Rogers, R.
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3. (a) Zaman, S.; Mitsuru, K.; Abell, A. D. Org. Lett. 2005, 7, 609e611; (b) Tabolin, A.
A.; Ioffe, S. L. Chem. Rev. 2014, 114, 5426e5476.
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Lin, C. C.; Hsieh, T. H.; Liao, P. Y.; Liao, Z. Y.; Chang, C. W.; Shih, Y. C.; Yeh, W. H.;
Chien, T. C. Org. Lett. 2014, 16, 892e895.
1
161.81 (d, JCeF¼253.1 Hz), 148.63, 148.02, 147.80, 146.34, 146.23,
146.07, 146.03, 145.97, 145.74, 145.73, 145.68, 145.20, 145.12, 144.84,
144.69, 144.10, 144.08, 143.08, 142.91, 142.81, 142.64, 142.44, 142.27,
142.25, 142.14, 142.07, 141.75, 140.57, 137.15, 136.50 (d,
4JCeF¼3.2 Hz), 135.67, 132.09 (d, JCeF¼8.6 Hz), 131.34 (d,
3
3JCeF¼8.6 Hz), 125.57 (d, JCeF¼3.2 Hz), 116.92 (d, JCeF¼22.7 Hz),
4
2
115.64 (d, 2JCeF¼21.8 Hz), 93.41 (sp3-C of C60), 86.74 (sp3-C of C60);
5. (a) Wang, Y.; Miller, R. L.; Sauer, D. R.; Djuric, S. W. Org. Lett. 2005, 7, 925e928;
UVevis (CHCl3) lmax/nm 257, 317, 429, 536, 692; FTIR n
/cmꢁ1 (KBr)
(b) Benltifa, M.; Vidal, S.; Fenet, B.; Msaddek, M.; Goekjian, P. G.; Praly, J. P.;
ꢀ
Brunyanszki, A.; Docsa, T.; Gergely, P. Eur. J. Org. Chem. 2006, 4242e4256; (c)
2920, 2849, 1608, 1577, 1506, 1409, 1369, 1292, 1232, 1183, 1153,
Candeias, N. R.; Branco, L. C.; Gois, P. M.; Afonso, C. A.; Trindade, A. F. Chem.
Rev. 2009, 109, 2703e2802; (d) Augustine, J. K.; Akabote, V.; Hegde, S. G.;
Alagarsamy, P. J. Org. Chem. 2009, 74, 5640e5643; (e) Martins, M. A.; Frizzo,
C. P.; Moreira, D. N.; Buriol, L.; Machado, P. Chem. Rev. 2009, 109, 4140e4182;
(f) Gerfaud, T.; Wei, H. L.; Neuville, L.; Zhu, J. Org. Lett. 2011, 13, 6172e6175; (g)
Kandre, S.; Bhagat, P. R.; Sharma, R.; Gupte, A. Tetrahedron Lett. 2013, 54,
3526e3529; (h) Goldberg, K.; Clarke, D. S.; Scott, J. S. Tetrahedron Lett. 2014,
55, 4433e4436; (i) Andersen, T. L.; Caneschi, W.; Ayoub, A.; Lindhardt, A. T.;
Couri, M. R.; Skrydstrup, T. Adv. Synth. Catal. 2014, 356, 3074e3082.
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2015, 80, 1789e1794.
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Tetrahedron 2010, 66, 5467e5471; (b) Lu, B. Q.; Zhang, J. M.; Li, J.; Yao, J. H.;
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89, 971e980; (d) Chen, X. L.; He, S. S.; Shen, S. B.; Zhao, J. W.; Zhang, J. M.; Zhu,
S. Z. Synthesis 2012, 44, 2347e2352; (e) Shang, W. L.; Zhang, J. M.; Chen, X. L.;
Zou, Y. H.; He, S. S.; Zhao, J. W.; Zhu, S. Z. Synthesis 2012, 44, 2575e2578; (f)
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hedron 2014, 70, 5828e5833.
1092, 1006, 840, 582, 526; MALDI-FTICR MS m/z Calcd for
C
73H9N2F2 [MþH]þ 951.0728, Found 951.0717.
3o: Black solid (7.3 mg, 15%); 1H NMR (500 MHz, CDCl3)
7.41e7.36 (m, 4H), 7.34e7.26 (m, 5H), 3.41e3.35 (m, 2H),
d
2.97e2.92 (m, 2H), 2.39 (s, 3H); 13C NMR (125 MHz, CDCl3)
d
165.80
(C]N), 149.27, 148.11, 147.93, 146.41, 146.33, 146.16, 146.13, 146.03,
146.02, 146.00, 145.77, 145.29, 145.21, 145.19, 144.81, 144.25, 144.13,
142.99, 142.89, 142.69, 142.54, 142.51, 142.48, 142.29, 142.17, 141.82,
141.00, 140.60, 139.64, 139.19, 137.04, 135.84, 134.92, 130.77, 130.57,
129.03, 128.74, 126.63, 93.62 (sp3-C of C60), 86.44 (sp3-C of C60),
33.54, 30.91, 21.46; UVevis (CHCl3) lmax/nm 256, 316, 428, 537, 691;
FTIR n
/cmꢁ1 (KBr) 2919, 2850, 1602, 1505, 1448, 1391, 1262, 1176,
1141, 1109, 1069, 1006, 797, 738, 697, 567, 526; MALDI-FTICR MS m/z
Calcd for C76H17N2 [MþH]þ 957.1386, Found 957.1383.
3p: Black solid (11.8 mg, 25%); 1H NMR (500 MHz, CDCl3/CS2)
8. (a) Brabec, C. J.; Sariciftci, N. S.; Hummelen, J. C. Adv. Funct. Mater. 2001, 11,
15e26; (b) Nakamura, E.; Isobe, H. Acc. Chem. Res. 2003, 36, 807e815; (c) Guldi,
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poulos, M. Chem. Soc. Rev. 2010, 39, 817e844; (e) Li, C. Z.; Yip, H. L.; Jen, A. K. Y. J.
Mater. Chem. 2012, 22, 4161e4177; (f) Tzirakis, M. D.; Orfanopoulos, M. Chem.
Rev. 2013, 113, 5262e5321; (g) Jennepalli, S.; Pyne, S. G.; Keller, P. A. RSC Adv.
2014, 4, 46383e46398.
9. He, C. L.; Liu, R.; Li, D. D.; Zhu, S. E.; Wang, G. W. Org. Lett. 2013, 15, 1532e1535.
10. (a) Yang, H. T.; Liang, X. C.; Wang, Y. H.; Yang, Y.; Sun, X. Q.; Miao, C. B. Org. Lett.
2013, 15, 4650e4653; (b) Yang, H. T.; Xing, M. L.; Lu, X. W.; Li, J. X.; Cheng, J.;
Sun, X. Q.; Miao, C. B. J. Org. Chem. 2014, 79, 11744e11749.
d
8.04 (d, J¼8.0 Hz, 2H), 7.57 (d, J¼7.6 Hz, 2H), 7.41 (d, J¼8.1 Hz, 2H),
7.32 (t, J¼7.7 Hz, 2H), 7.23 (t, J¼7.4 Hz, 1H), 5.38 (s, 2H), 2.52 (s, 3H);
13C NMR (125 MHz, CDCl3/CS2)
166.36 (C]N), 149.99, 147.85,
d
147.62, 146.18, 146.08, 145.95, 145.90, 145.83, 145.64, 145.54, 145.08,
144.97, 144.73, 144.62, 143.99, 143.89, 142.79, 142.66, 142.49,142.27,
142.20, 142.12, 142.11, 142.01, 141.55, 141.20, 140.44, 139.00, 137.02,
136.68, 135.52, 129.65, 128.92, 128.77, 127.73, 127.49, 127.07, 93.21
(sp3-C of C60), 84.91 (sp3-C of C60), 51.52, 21.71; UVevis (CHCl3)
lmax/nm 256, 317, 429, 537, 691; FTIR n
/cmꢁ1 (KBr) 2914, 2847,
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This work was supported by the National Natural Science
Foundation of China (No. 21272151). The authors acknowledge as-
sistance from the Analytical Chemistry Laboratory, Shanghai In-
stitute of Organic Chemistry, Chinese Academy of Sciences (Prof.
Qin Hua for the MALDI-FTICR-MS testing) and the NMR Laboratory,
Center of Analysis and Test, Shanghai University (Prof. Hongmei
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