BF3·Et2O- or DMAP-catalyzed double nucleophilic substitution reaction of aziridinofullerenes with sulfamides or amidines

Article abstract of DOI:10.1021/jo5020596

BF₃·Et₂O-catalyzed double nucleophilic substitution reaction of N-tosylaziridinofullerene with sulfamides has been exploited for the easy preparation of cyclic sulfamide-fused fullerene derivatives. Moreover, the Lewis base catalyzed

Full text of DOI:10.1021/jo5020596

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Note
BF3.Et2O or DMAP-Catalyzed Double Nucleophilic Substitution
Reaction of Aziridinofullerenes with Sulfamides or Amidines
Hai-Tao Yang, Meng-Lei Xing, Xin-Wei Lu, Jia-Xing Li, Jiang Cheng, Xiao-Qiang Sun, and Chun-Bao Miao
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/jo5020596 • Publication Date (Web): 04 Nov 2014
Downloaded from http://pubs.acs.org on November 12, 2014
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BF3⋅Et2O or DMAP-Catalyzed Double Nucleophilic Substitution Reaction of
Aziridinofullerenes with Sulfamides or Amidines
HaiꢀTao Yang,*,† MengꢀLei Xing,† XinꢀWei Lu,† JiaꢀXing Li,‡ Jiang Cheng,† XiaoꢀQiang Sun,† and, ChunꢀBao
Miao†
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† School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
‡ Key Laboratory of Novel Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Sciences, P.O.
Box 1126, Hefei 230031, China
Email: yht898@yahoo.com
R''
O O
S
loss of TsN unit
O O
Ts
N
R'
R'
R''
N
N
N
N
R''
R''
R'
S
N
H
N
H
R'
N
H2N
DMAP
•
BF3 Et2O
Abstract
BF3⋅Et2Oꢀcatalyzed double nucleophilic substitution reaction of Nꢀtosylaziridinofullerene with
sulfamides has been exploited for the easy preparation of cyclic sulfamideꢀfused fullerene
derivatives. Moreover, the Lewis baseꢀcatalyzed double amination of Nꢀtosylaziridinofullerene,
with amidines as the diamine source, is demonstrated for the first time. The present methods
provide new routes to cyclic 1,2ꢀdiaminated [60]fullerenes.
Chemical modification of fullerenes,1 which can adjust the physical, chemical, biological, and
electronic properties and solubility, has been an attractive research field for designing more
fullerene derivatives and investigating their application in different fields. The oneꢀstep reaction of
C60 with a variety of reactants is the most used method to prepare different fullerene derivatives.2
However, not all the derivatives can be easily prepared directly from C60. Thus, the development of
new methods to synthesize various functionalized fullerenes with new structure from an easily
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available precursor is an important endeavor. NꢀSulfonylated aziridinofullerene is one of the most
important classes of nitrogenꢀcontaining fullerene derivatives, which can be easily synthesized from
azides,3 chloramines,4 sulfilimines,5 iminophenyliodinanes,6 and N,Nꢀdihalosulfonamides.7 We
have also developed hypervalent iodine reagentsꢀmediated reaction of C60 with sulfonamides for the
preparation of aziridinofullerenes.8 The chemistry of aziridines is centered on ringꢀopening
reactions with a wide range of nucleophiles or formal [3+2] reactions with dipolarophiles as a
consequence of their ring strain.9 These reactions have led to the formation of various important
1,2ꢀdifunctionalized scaffolds and fiveꢀmembered ring heterocycles. Recently, a novel tandem
ringꢀopening/closing reaction of aziridines with those substrates containing two functional groups
(NuꢀꢀꢀE) has attracted more attention for the synthesis of fiveꢀ to sevenꢀmembered ring heterocycles
(Scheme 1).9h, 10 In these transformations the “TsN” unit was reserved in the product. In case of the
Nꢀsulfonylated aziridinofullerenes, besides the classic formal [3+2] reactions with CO2,
arylisocyanates, 11 and carbonyls, 12 they could also undergo unique acidꢀcatalyzed double
nucleophilic substitution reaction with aromatic compounds or bifunctional nucleophiles
accompanying with the loss of sulfonamides.6, 13 Under the guidance of this new methodology, we
envisioned that 1,3ꢀdiamines, which contained two nucleophilic sites, might react with
Nꢀsulfonylated aziridinofullerenes to generate cyclic 1,2ꢀdiaminated [60]fullerenes. Compared to
the recently emerged transitionꢀmetalꢀcatalyzed or promoted oxidative intramolecular diamination
of olefin, which has been a suitable approach to generate bicyclic heterocycles with two nitrogen
atoms (Scheme 1),14 this would be a new route to generate cyclic diamination products of alkenes.
Up to now, the direct diamination of C60 with sulfamides and ureas is still a challenge partially due
to the unfavorability of intermolecular reaction. Only a few reports have appeared for the
preparation of C60ꢀfused fiveꢀmembered ring heterocyclic derivatives with two nitrogen atoms
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directly linking to C60. The Ag2CO3ꢀmediated or CuIꢀcatalyzed oxidative cycloaddition of C60 with
amidines for the preparation of fulleroimidazoles was developed by the Wang groups and us,
respectively.15 Minakata and coworkers explored a formal [3+2] reaction of Nꢀsufonylated
aziridinofullerene with aryl isocyanates for the preparation of C60ꢀfused cyclic urea derivatives.11
Most recently, we developed a hypervalent iodineꢀmediated diamination of C60 with sulfamides or
phosphoryl diamides for the preparation of novel C60ꢀfused cyclic sulfamide or C60ꢀfused
phosphoryl diamide derivatives.16
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In continuation of our interest in fullerene chemistry,8,12,16,17 we reported here the BF3⋅Et2O or
DMAPꢀcatalyzed reaction of Nꢀtosylaziridinofullerenes with sulfamides or amidines for the easy
preparation of cyclic 1,2ꢀdiaminated [60]fullerenes (Scheme 1).
Scheme 1
Previous work on azirdines:
Ts
N
Ts
N
R
H
A
H
B
Ts
N
A
or
Ts
N
A
B
B
Nu
E
E
R
Nu
R
R
Nu
Nu
NHTs
reserve of TsN unit
R
Documented diamination of alkenes:
X
X
R
R
N
N
N
H
N
H
[Ni], [Pd], [Au], [Cu]
X = CO, SO2
or
or
R
R
N
N
N
H
NH
mostly intramolecular fashion
This work:
loss of TsN unit
O
O
R''
Ts
N
S
R'
R''
R'
N
N
N
N
O
O
S
R'
or
R''
R'
N
N
H
H
or
R''
N
HN
H
(1) intermolecular fashion; (2) metal-free
Initially, the Nꢀtosylaziridinofullerene 1 and N,N'ꢀdibutylsulfamide 2a were reacted in dry
chlorobenzene using BF3⋅Et2O as the catalyst, which was the effective Lewis acid catalyst in our
previously reported conditions for the reaction of 1 with carbonyl compounds (Scheme 2).12 In the
presence of 5 equiv of BF3⋅Et2O, the desired cyclic 1,2ꢀdiaminated product 3a was obtained in 76%
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yield after stirring for 65 min at room temperature. Decreasing the amount of BF3⋅Et2O to 1.5 equiv
led to a longer reaction time and lower yield.
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Scheme 2 BF3⋅Et2O-Catalyzed Reaction of Aziridinofullerene 1 with N,N'-Dibutylsulfamide 2a
9
O O
Ts
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S
n
n
C4H9
C4H9
N
N
N
O O
S
•
BF3 Et2O
n
n
C4H9
C4H9
+
N
N
H
PhCl
H
2a
(1.5 equiv)
1
3a
76%
(2) 1.5 equiv of BF3•E 2O, 120 min, 47%
•E
(1) 5 equiv of BF3 t2O, 65 min,
t
Using BF3⋅Et2O as the catalyst, we examined the generality of this kind of double nucleophilic
substitution reaction (Table 1). When R1 and R2 were both alkyl group, the reaction proceeded well
to give the desired products in good yield (Table 1, entries 1–8). Replacing one of the substituent on
nitrogen atom by aryl group resulted in the failure of reaction (Table 1, entry 9). It should be noted
that this kind of transformation has a merit in contrast to our recently reported PhIO/I2ꢀmediated
diamination of C60 with sulfamides,16 that was, the alkenyl and alkynyl groups were also tolerated
to afford good yields of 3g and 3h (Table 1, entries 7 and 8). Moreover, we were fortunate to find
that aryl substituted sulfamides were also applicable to the reaction, affording the desired products
3i and 3j, respectively. Under PhIO/I2 conditions, no reaction occurred for substrates 2gꢀj.
Interestingly, when the mono substituted sulfamide 2k was subjected to the reaction, product 3k
was also furnished in excellent yield. The presence of NꢀH unit in compound 3k allowed their
further transformation to other more complicated fullerene derivatives.
Table 1 Substrate Scope for the BF3⋅Et2O-Catalyzed Reaction of Aziridinofullerene 1 with
Sulfamides
Ts
R1
R2
N
O O
S
R1
R2
BF3•Et2O (5 equiv)
PhCl, rt.
+
N
N
H
H
2
(1.5 equiv)
1
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time
entry
carbonyls
product
3a
yield (%)a
(min)
2a
C4H9
O
O
n
n
1
2
3
4
5
6
7
8
65
30
76
88
74
58
80
77
79
90
S
C4H9
N
H
N
H
2b
PhCH2
O
O
3b
S
CH2Ph
N
H
N
H
9
2c
C4H9
O
O
n
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3c
S
CH2Ph
N
H
N
H
2d
C4H9
O
O
n
3d
120
45
S
N
H
N
H
2e
PhCH2
O
O
3e
S
N
H
N
H
2f
C4H9
O
O
n
120
20
3f
S
N
H
N
H
CO2Et
2g
PhCH2
O
O
3g
S
N
H
N
H
2h
PhCH2
O
O
20
3h
S
N
H
N
H
2i
PhCH2
O
O
9
20
82
3i
S
N
H
N
H
O
O
10
11
20
20
83
65
3j
2j
S
N
H
N
H
2k
PhCH2
O
O
3k
S
N
H
NH2
a Isolated yield.
Amidines as another commonly used precursor in the diamination of olefins also contained
two nucleophilic sites (Figure 1). On the basis of known reactivity of Nꢀtosylaziridinofullerene, we
envisioned a new method to produce the fulleroimidazoles by the Lewis acidꢀcatalyzed reaction of
amidines with Nꢀtosylaziridinofullerene 1. To explore this approach, a model reaction between 1
and Nꢀ(pꢀtolyl)ꢀ4ꢀmethylbenzamidine 4a was carried out in the presence of 5 equiv of BF3⋅Et2O. No
expected product 5a was detected and most of 1 was converted to C60 (Table 2, entry 1). Other
commonly used acid catalysts including Zn(OTf)2, Sc(OTf)3, trifluoromethanesulfonic acid (TfOH),
and methanesulfonic acid (MSA) were also ineffective (Table 2, entries 2ꢀ5). In the presence of
TfOH at room temperature or MSA at 100 ºC, most of 1 was transformed to C60. In terms of
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Zn(OTf)2 and Sc(OTf)3, no reaction was observed and 1 was totally recovered. Later on, the
combination of Sc(OTf)3 with a ligand was tried (Figure 1). An interesting phenomenon was
observed. When 1 equiv of 2,2'ꢀisopropylidenebisoxazoline (BOX, Figure 1) was added as the
ligand, trace of desired product 5a was observed on TLC (Table 2, entry 6). Increasing the amount
of BOX to 8 equiv improved the yield to 21% (Table 2, entry 7). Replacing the BOX by Bpy gave
similar result and afforded 5a in 15% yield (Table 2, entry 8). This reminded us the metal salts may
not play an actual catalytic role in the reaction. In the absence of metal salts, treatment of 1 and 4a
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o
with 1 equiv of 2,2'ꢀbipyridine (Bpy) at 100 C for 6 h indeed provided 5a in 32% yield (Table 2,
entry 9). The fact that DMAP could also catalyze the transformation demonstrated the ligands BOX
and Bpy only played the role of a base. This was the first example of baseꢀcatalyzed double
nucleophilic substitution reaction of Nꢀtosylaziridinofullerene. To the best of our knowledge, the
most similar conversion was the Et3Nꢀcatalyzed reaction of oxiranes with benzamidines for the
preparation of imidazoles18 and in which the oxirane O was maintained in the product. Other
commonly used bases such as Et3N, DBU, and K2CO3 were also screened (Table 2, entries 11ꢀ13).
Et3N and K2CO3 showed lower catalytic activity than DMAP. Using DBU as the base led to full
transformation of Nꢀtosylaziridinofullerene 1 to C60 and unidentified product with very high polarity
within half an hour. Catalytic amount of DMAP (0.2 equiv) gave a higher yield of 5a (Table 2, entry
15). Reducing the temperature to 70 °C led to a longer reaction time and lower yield of 5a (Table 2,
entry 14). It was worth noting that both O2 and H2O have no influence on the reaction. However, in
the recently reported PCy3ꢀcatalyzed formal [3+2] reaction of Nꢀsulfonylated aziridinofullerenes
with CO2 or arylisocyanates,11 anhydrous and oxygenꢀfree operations were indispensable.
Eventually, the molar ratio of C60:4a:DMAP as 1:1.5:0.2 and the reaction temperature as 100 °C
were selected as the optimal condition for subsequent investigation of the double nucleophlic
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substitution of Nꢀtosylaziridinofullerene 1 with amidines (Table 3).
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Figure 1 Structure of Sulfamide, Amidine, and BOX
R2
O O
R2
R1
S
R2
O
O
R1
R1
N
H
N
H
N
H
N
H
N
NH2
N
N
9
Sulfamide
Amidine
BOX
10
11
12
13
14
15
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Table 2 Screening of the Reaction Conditionsa
H2N
N
conditions
N
Ts
+
N
N
4a
1
5a
entr
y
1/4a/add
itives
time
yield
additives
BF3⋅Et2O
T (ºC)
(h)
6
(%)b
1
1:1.5:5
1:1.5:1
1:1.5:1
1:1.5:1
1:1.5:1
rt
rt
0
2
TfOH
0.5
2
0
3
MSA
rt or 100
rt or 100
rt or 100
100
0
4
Zn(OTf)2
Sc(OTf)3
6
0
5
6
0
6
Sc(OTf)3/BOX 1:1.5:1:1
Sc(OTf)3/BOX 1:1.5:1:8
6
trace
21
15
32
81
30
0
7
100
8
8
Sc(OTf)3/Bpy
Bpy
1:1.5:1:8
1:1.5:1
1:1.5:1
1:1.5:1
1:1.5:1
1:1.5:1
1:1.5:1
1:1.5:0.2
1:1.5:0.2
100
8
9
100
6
10
11
12
13
DMAP
Et3N
100
1
100
5
DBU
rt
0.25
6
K2CO3
100
44
70
87
85
14c DMAP
15 DMAP
16d DMAP
100
1
100
4
100
5
a
Unless otherwise noted, the reactions were carried out with 0.02 mmol of 1 and proper additives in 3.5 mL of
dry chlorobenzene. b Isolated yield. c The reaction was operated at 70 °C. d The reaction was carried out under N2
atmosphere with the 4Å molecular sieve as additive.
Amidines with both aryl substituents gave good yield of fulleroimidazoles 5 (Table 3, entries
1–9). The electronic effect of the substituent group on the phenyl ring did not significantly influence
the reaction efficiency. Fortunately, amidine 4l bearing a tosyl group on the nitrogen atom also
afforded the product 5l in 61% yield, albeit much longer reaction time and 3 equiv of DMAP were
needed (Table 3, entry 12). However, the reaction of C60 with 4l under our recently reported
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CuI/Phen conditions,15b which was effective catalytic system for the preparation of
fulleroimidazoles, did not generate 5l. It is a pity that no reaction occurred when either R1 or R2 was
an alkyl group (Table 3, entries 10 and 11).
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Table 3. DMAP-Catalyzed Reaction of Aziridinofullerene 1 with Amidines for the Synthesis of
Fulleroimidazoles
NH2
R2
N
N
R1
DMAP (0.2 equiv)
R1
R2
N
Ts
+
PhCl, 100 o
C
N
4
1
(1.5 equiv)
5
entry
1
substrate
product
time (h)
4
yielda
87
H2N
5a
N
H2
N
N
2
3
4
5
6
7
8
5
5
6
5
4
4
6
83
86
92
82
81
91
70
5b
5c
5d
5e
5f
MeO
H2N
N
Cl
H2N
N
O2N
H2N
N
H2N
N
OMe
NO2
OMe
H2N
N
5g
5h
H2N
MeO
N
H2N
9
4
83
5i
N
H2N
N
CH2Ph
10
11
12
12
30
0
0
5j
5k
5l
H2N
n-Bu
N
HN
12b
61
Ts NH
a Isolated yield. b 1:4l:DMAP = 1:2:3.
The identities of known compounds were confirmed through comparison of their TLC with those
obtained from our previous work and their spectral data with those reported in the literatures.15,16
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New compounds 4g, 4h, and 5l were unambiguously characterized by their HRMS, H NMR, 13C
4
5
6
NMR, and UVꢀvis spectra.
7
8
9
In summary, BF3⋅Et2O or DMAPꢀcatalyzed double nucleophilic reaction of
Nꢀtosylaziridinofullerene with sulfamides or amidines has been developed for the easy preparation
of cyclic 1,2ꢀdiaminated fullerenes. This protocol is attractive in view of mild and metalꢀfree
conditions, cheap and easily available catalyst, and high yield of product. For the first time, this
kind of double nucleophilic reaction of Nꢀtosylaziridinofullerene was realized using a Lewis base as
catalyst when amidines were chosen as the nucleophilic reagent. In contrast to our recently
developed methodology for the preparation of C60ꢀfused cyclic sulfamides through hypervalent
iodineꢀmediated diamination of C60 with sulfamides, the BF3⋅Et2Oꢀcatalyzed transformation showed
better functional group tolerance and gave better yield. Further investigations on the Lewis acid or
baseꢀcatalyzed reaction of Nꢀtosylaziridinofullerene with other compounds containing 1,3ꢀ or
1,4ꢀdouble nucleophilic sites are currently underway.
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Experimental Section
The Known Sulfamides 2 and Amidines 4 were Prepared as Described in Our Recent Works
and Literatures.16,19
Preparation of 2g and 2h
A solution of 2ꢀbromoethanol (1.25 g, 10 mmol) in 4 mL of dry dichloromethane was added
dropwise to a stirred solution of chlorosulfonyl isocyanate (1.41 g, 10 mmol) in 10 mL of dry
dichloromethane at 0 °C over 20 min. After further stirring for 40 min at room temperature, the
mixture was cooled to 0 °C with an ice bath. Benzylamine (1.17 g, 11 mmol) and triethylamine
(2.53 g, 25 mmol) in 8 mL of dry dichloromethane were added dropwise to the mixtrure. After
completion of the addition, the mixture was allowed to warm to room temperature and continued to
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stir for 2 h. Then the mixture was washed with aqueous hydrochloric acid (0.1 N, 20 mL × 2), water
(20 mL), saturated sodium bicarbonate, and dried over anhydrous Na2SO4. The filtrate was
concentrated under vacuum to afford the crude product.
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A mixture of the above crude product (256 mg, 1 mmol), allylamine or 2ꢀpropynylamine (5
equiv), and triethylamine (0.25 g, 2.5 mmol) in 10 mL of acetonitrile was heated at reflux for 6 h.
After cooling to room temperature, the mixture was diluted with 20 mL of ethyl acetate, and then
washed with aqueous hydrochloric acid (0.1 N, 20 mL × 2), water (20 mL), saturated sodium
bicarbonate, and dried over anhydrous Na2SO4. The solvent was removed under reduced pressure to
give the crude product as a colorless solid. The crude product was further purified by column
chromatography (EtOAc/petroleum ether) to provide final product 2g (163 mg, 72%) or 2h (156 mg,
70%).
2g: colorless solid, mp: 108–109 °C; 1H NMR (300 MHz, CDCl3) δ 7.30–7.39 (m, 5H), 5.81 (ddt, J
= 17.0, 10.2, 5.9 Hz, 1H), 5.24 (dq, J = 17.1, 1.5 Hz, 1H), 5.17 (dq, J = 10.2, 1.3 Hz, 1H), 4.48 (br,
1H), 4.23 (d, J = 6.0 Hz, 1H), 4.16 (br, 1H), 3.62 (tt, J = 6.1, 1.4 Hz, 1H); 13C NMR (75 MHz,
CDCl3) δ 136.78, 133.31, 128.93, 128.19, 128.14, 117.94, 47.39, 45.84; FTꢀIR ν/cmꢀ1 (KBr) 3288,
3269, 3086, 3065, 3034, 3012, 2937, 2847, 1495, 1454, 1437, 1423, 1342, 1317, 1148, 1086, 1065,
1043, 987, 930, 906, 731, 696, 534; HRMS (+ESI) m/z [M+Na]+ calcd for C10H14N2NaO2S
249.0674, found 249.0669.
2h: colorless solid, Mp: 64–65 °C; 1H NMR (300 MHz, CDCl3) δ 7.30–7.40 (m, 5H), 4.55 (br, 1H),
4.44 (br, 1H), 4.27 (d, J = 6.2 Hz, 1H), 3.87 (dd, J = 6.1, 2.5 Hz, 2 H), 2.32 (t, J = 2.5 Hz, 1H); 13C
NMR (75 MHz, CDCl3) δ 136.45, 128.94, 128.27, 128.21, 78.98, 73.03, 47.52, 32.89; FTꢀIR ν/cmꢀ1
(KBr) 3292, 3269, 3065, 3032, 2924, 2847, 2129, 1495, 1454, 1437, 1420, 1358, 1319, 1150, 1068,
910, 727, 696, 679, 646, 582, 532; HRMS (+ESI) m/z [M+Na]+ calcd for C10H12N2NaO2S 247.0517,
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found 247.0513.
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General Procedure for the BF3⋅Et2O-Catalyzed Reaction of N-Tosylaziridinofullerene 1 with
Sulfamides
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BF3⋅Et2O (12 ꢁL, 0.1 mmol) was added in one potion to a solution of NꢀTosylaziridinofullerene 1
(17.8 mg, 0.02 mmol) and sulfamides 2 (0.03 mmol) in 3 mL of dry chlorobenzene. The mixture
was stirred at room temperature until the disappearance of 1 determined by TLC. The solvent was
removed under reduced pressure, and the residue was purified on a silica gel column using
CS2/toluene as the eluent to give the products 3 (3a, 14.1 mg; 3b, 17.4 mg; 3c, 14.3 mg; 3d, 11.0
mg; 3e, 15.8 mg; 3f, 14.8 mg; 3g, 14.9 mg; 3h, 16.9 mg; 3i, 16.4 mg; 3j, 16.5 mg; 3k, 11.8 mg;).
3a: 1H NMR (400 MHz, CS2ꢀCDCl3) δ 4.05 (t, J = 7.5 Hz, 4H), 2.13 (quint, 4H, J = 7.5 Hz), 1.60
(sextet, 4H, J = 7.5 Hz), 1.03 (t, J = 7.4 Hz, 6H); 13C NMR (10 MHz, CS2ꢀCDCl3) δ 148.30, 146.62,
146.56, 146.35, 146.18, 145.54, 145.33, 144.74, 144.39, 143.07, 142.91, 142.34, 141.92, 141.66,
139.43, 137.73, 79.29 (sp3ꢀC of C60), 46.05, 31.97, 20.67, 13.99.
3g (brown solid, mp > 300 °C): 1H NMR (500 MHz, CS2ꢀCDCl3) δ 7.57 (d, J = 7.4 Hz, 2H), 7.27 (t,
J = 7.4 Hz, 2H), 7.21 (t, J = 7.4 Hz, 1H), 6.34 (ddt, J = 17.1, 10.2, 6.1 Hz, 1H), 5.51 (dq, J = 17.1,
1.4 Hz, 1H), 5.35 (dq, J = 10.3, 1.3 Hz, 1H), 5.23 (s, 2H), 4.74 (dt, J = 6.1, 1.4 Hz, 2H); 13C NMR
(125 MHz, CS2ꢀCDCl3) δ 148.17, 146.56, 146.51, 146.27, 146.26, 146.17, 146.07, 146.03, 145.42,
145.24, 144.68, 144.61, 144.59, 144.40, 142.91, 142.81, 142.80, 142.26, 141.86, 141.74, 141.49,
141.39, 139.20, 138.89, 137.76, 137.31, 135.77, 133.22, 128.83, 128.64, 128.12, 119.78, 79.19
(sp3ꢀC of C60), 79.13 (sp3ꢀC of C60), 49.64, 48.71; UVꢀVis (CHCl3) λmax/nm 256, 319, 420, 685;
FTꢀIR ν/cmꢀ1 (KBr) 2920, 2849, 1437, 1315, 1178, 1161, 1103, 1065, 926, 901, 851, 795, 731, 696,
527; HRMS (MALDIꢀTOFMS) m/z [M+Na]+ calcd for C70H12N2NaO2S 967.0517, found 967.0514.
3h (brown solid, mp > 300 °C): 1H NMR (500 MHz, CS2ꢀCDCl3) δ 7.59 (d, J = 7.3 Hz, 2H), 7.27 (t,
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J = 7.4 Hz, 2H), 7.20 (t, J = 7.5 Hz, 1H), 5.23 (s, 2H), 4.90 (d, J = 2.5 Hz, 2H), 2.49 (t, J = 2.5 Hz,
1H); 3h has a very poor solubility, which make it difficult to be characterized by 13C NMR analysis
(only a spectrum with low resolution was achieved); UVꢀVis (CHCl3) λmax/nm 256, 318, 420, 685;
FTꢀIR ν/cmꢀ1 (KBr) 3263, 2922, 2133, 1512, 1454, 1435, 1367, 1321, 1167, 1130, 1094, 1065, 947,
922, 795, 741, 694, 527; HRMS (MALDIꢀTOFMS) m/z [M+Na]+ calcd for C70H10N2NaO2S
965.0361, found 965.0357.
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3i (brown solid, mp > 300 °C): 1H NMR (400 MHz, CS2ꢀCDCl3) δ 7.81 (d, J = 8.3 Hz, 2H), 7.63 (d,
J = 7.4 Hz, 2H), 7.25ꢀ7.33 (m, 4H), 7.21 (t, J = 7.2 Hz, 1H), 5.31 (s, 2H), 2.41 (s, 3H); 13C NMR
(100 MHz, CS2ꢀCDCl3) δ 148.23, 148.17, 146.53, 146.40, 146.27, 146.25, 146.15, 146.11, 145.44,
145.23, 145.21, 144.75, 144.60, 144.42, 142.88, 142.79, 142.77, 142.31, 142.14, 141.83, 141.79,
141.54, 141.49, 140.17, 139.35, 138.84, 137.43, 137.28, 135.81, 131.53, 131.35, 130.37, 128.97,
128.65, 128.13, 80.65 (sp3ꢀC of C60), 79.38 (sp3ꢀC of C60), 50.08, 21.50; UVꢀVis (CHCl3) λmax/nm
258, 320, 420, 687; FTꢀIR ν/cmꢀ1 (KBr) 2920, 2851, 1508, 1454, 1437, 1365, 1331, 1169, 1022, 743,
696, 550, 527; HRMS (MALDIꢀTOFMS) m/z [M+Na]+ calcd for C74H14N2NaO2S 1017.0674,
found 1017.0668.
3j (brown solid, mp > 300 °C): 1H NMR (400 MHz, CS2ꢀCDCl3) δ 7.87 (d, J = 8.3 Hz, 4H), 7.30 (d,
13
J = 8.1 Hz, 4H), 2.41 (s, 6H); C NMR (100 MHz, CS2ꢀCDCl3) δ 148.26, 146.53, 146.30, 146.27,
146.17, 145.47, 145.21, 144.65, 144.63, 142.87, 142.77, 142.21, 141.89, 141.68, 140.23, 139.34,
137.33, 131.78, 131.25, 130.39, 80.55 (sp3ꢀC of C60), 21.51; UVꢀVis (CHCl3) λmax/nm 257, 319, 420,
687; FTꢀIR ν/cmꢀ1 (KBr) 2918, 2849, 1506, 1434, 1369, 1335, 1231, 1171, 1022, 1003, 640, 548,
527; HRMS (MALDIꢀTOFMS) m/z [M+Na]+ calcd for C74H14N2NaO2S 1017.0674, found
1017.0667.
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3k (brown solid, mp > 300 °C): H NMR (500 MHz, CS2ꢀDMSOꢀd6) δ 10.48 (s, 1H), 7.62 (d, J =
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7.3 Hz, 2H), 7.32 (t, J = 7.5 Hz, 2H), 7.25 (t, J = 7.4 Hz, 1H), 5.11 (s, 2H); 13C NMR (125 MHz,
CS2ꢀDMSOꢀd6) δ 148.66, 147.29, 147.21, 145.81, 145.60, 145.59, 145.36, 145.32, 145.23, 145.06,
144.74, 144.38, 144.36, 144.16, 143.97, 143.88, 143.67, 141.99, 141.89, 141.77, 141.48, 141.30,
141.07, 140.77, 140.52, 138.98, 137.87, 136.84, 136.38, 135.44, 128.10, 127.69, 127.08, 79.29
(sp3ꢀC of C60), 75.24 (sp3ꢀC of C60), 48.32; UVꢀVis (CHCl3) λmax/nm 257, 319, 420, 686; FTꢀIR
ν/cmꢀ1 (KBr) 3221, 2920, 2850, 1510, 1389, 1321, 1180, 1130, 1049, 750, 696, 550, 527; HRMS
(MALDIꢀTOFMS) m/z [M+Na]+ calcd for C67H8N2NaO2S 927.0204, found 927.0199.
General Procedure for the DMAP-Catalyzed Reaction of N-Tosylaziridinofullerene 1 with
Amidines 4
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A 0.1 mol/L of DMAP solution (for 4aꢀk, 40 uL, 0.004 mmol; for 4l, 7.3 mg DMAP was used
directly, 0.06 mmol) in dry chlorobenzene was added to the solution of Nꢀtosylaziridinofullerene
(17.8 mg, 0.02 mmol) and amidines 4 (0.03 mmol) in 3 mL of dry chlorobenzene. The mixture was
stirred at 100 °C until the disappearance of 1 detected by TLC. The solvent was removed under
reduced pressure, and the residue was purified on a silica gel column using CS2/toluene as the
eluent to give the products 5 (5a, 16.4 mg; 5b, 16.0 mg; 5c, 16.5 mg; 5d, 18.0 mg; 5e, 15.2 mg; 5f,
15.5 mg; 5g, 17.7 mg; 5h, 13.6 mg; 5i, 15.4 mg; 5l, 12.2 mg).
5a: 1H NMR (500 MHz, CS2ꢀCDCl3) δ 7.80 (d, J = 8.0 Hz, 2H), 7.44 (d, J = 8.1 Hz, 2H), 7.18 (d, J
= 8.1 Hz, 2H), 7.16 (d, J = 8.1 Hz, 2H), 2.42 (s, 3H), 2.34 (s, 3H); 13C NMR (125 MHz, CS2ꢀCDCl3)
δ 164.23 (C=N), 149.12, 147.98, 147.76, 146.28, 146.18, 146.01, 145.97, 145.91, 145.87, 145.85,
145.61, 145.21, 145.14, 145.07, 144.69, 144.67, 144.12, 142.86, 142.75, 142.58, 142.43, 142.34,
142.13, 142.08, 141.71, 140.87, 140.49, 139.43, 138.18, 137.72, 137.06, 135.72, 130.42, 129.91,
129.48, 129.04, 126.91, 93.48 (sp3ꢀC of C60), 86.85 (sp3ꢀC of C60), 21.69, 21.38;
5l (brown solid, mp > 300 °C): 1H NMR (400 MHz, CS2ꢀCDCl3) δ 7.90 (d, J = 7.2 Hz, 2H), 7.61 (t,
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J = 7.4 Hz,1H), 7.53 (t, J = 7.4 Hz, 2H), 7.49 (d, J = 8.4 Hz, 2H), 7.22 (d, J = 8.4 Hz, 2H), 2.46 (s,
3H); 13C NMR (100 MHz, CS2ꢀCDCl3) δ 160.95 (C=N), 148.06, 148.04, 147.74, 146.58, 146.50,
146.43, 146.26, 146.24, 146.03, 145.73, 145.66, 145.29, 145.27, 145.20, 144.95, 144.57, 144.24,
143.18, 142.86, 142.81, 142.56, 142.39, 142.16, 141.87, 141.80, 141.77, 140.70, 138.40, 136.81,
136.75, 135.47, 130.75, 130.28, 130.02, 129.62, 128.14, 127.82, 93.35 (sp3ꢀC of C60), 83.37 (sp3ꢀC
of C60), 21.84; UVꢀVis (CHCl3) λmax/nm 256, 317, 419, 686; FTꢀIR ν/cmꢀ1 (KBr) 2920, 2851, 1624,
1595, 1516, 1371, 1313, 1167, 1088, 1026, 767, 663, 615, 588, 546, 527; HRMS (MALDIꢀTOFMS)
m/z [M+H]+ calcd for C74H13N2O2S 993.0698, found 993.0693.
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Acknowledgment
We are grateful for financial support from the National Natural Science Foundation of China
(Nos. 21202011 and 21272236), the Natural Science Foundation of Jiangsu Province
(BK20141171), the Priority Academic Program Development of Jiangsu Higher Education
Institutions (PAPD), and the Jiangsu Key Laboratory of Advanced Catalytic Materials and
Technology (BM2012110).
Supporting Information
1
1H NMR and 13C NMR spectra of the products 2gꢀj, 3a, 3gꢀk, 5a, and 5l; H NMR spectra of the
known products 2k, 3bꢀh, and 5bꢀi; UVꢀvis spectra of 3j and 5l. This material is available free of
charge via the Internet at http://pubs.acs.org.
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