Synthesis of fulleropyrrolidines through the reaction of [60]fullerene with quaternary ammonium salts and amino acids

Article abstract of DOI:10.1016/j.tetlet.2009.07.097

The reactions of [60]fullerene with amino acids and quaternary ammonium salts in toluene afforded two fulleropyrrolidine derivatives. One fulleropyrrolidine derivative contained a RCH moiety originating from quaternary ammonium salts through C-N bond cleavages and other fulleropyrrolidine derivatives contained a PhCH moiety originating from toluene through C-H bond cleavage. By using chlorobenzene instead of toluene as solvent, only one fulleropyrrolidine derivative containing a RCH moiety was obtained in the reactions.

Full text of DOI:10.1016/j.tetlet.2009.07.097

Tetrahedron Letters 50 (2009) 5640–5643
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Tetrahedron Letters
journal homepage: www.elsevier.com/locate/tetlet
Synthesis of fulleropyrrolidines through the reaction of [60]fullerene
with quaternary ammonium salts and amino acids
a,
c
a
Bo Jin a,b, , Ru-Fang Peng , Juan Shen , Shi-Jin Chu
*
*
a Department of Chemistry, Southwest University of Science and Technology, Mianyang 621010, China
b School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing 100081, China
c Analytical & Testing Center, Sichuan University, Chengdu 610064, China
a r t i c l e i n f o
a b s t r a c t
Article history:
The reactions of [60]fullerene with amino acids and quaternary ammonium salts in toluene afforded two
fulleropyrrolidine derivatives. One fulleropyrrolidine derivative contained a RCH moiety originating from
quaternary ammonium salts through C–N bond cleavages and other fulleropyrrolidine derivatives con-
tained a PhCH moiety originating from toluene through C–H bond cleavage. By using chlorobenzene
instead of toluene as solvent, only one fulleropyrrolidine derivative containing a RCH moiety was
obtained in the reactions.
Received 6 April 2009
Revised 15 July 2009
Accepted 17 July 2009
Available online 22 July 2009
Keywords:
Fullerene
Ó 2009 Elsevier Ltd. All rights reserved.
Amino acids
Cycloaddition reaction
Quaternary ammonium salts
Since their first discovery and isolation, chemical modifications
of fullerene have been intensively explored and an impressive
number of fullerene derivatives have been synthesized by various
functionalization methods because of their potential applications
in many fields such as materials science and life science.1 Fullero-
pyrrolidines are one of fullerene derivatives frequently employed
in these fields.2 The reaction between azomethine ylides and ful-
lerene is one of the first reported fullerene reactions and has been
widely studied in order to synthesize fulleropyrrolidine deriva-
tives.3 A very simple and powerful way to afford azomethine ylides
is the decarboxylation of iminium salts derived from the condensa-
tion of amino acids and aldehydes/ketones.4 Azomethine ylides can
also be successfully generated by thermal ring opening of aziri-
dines3,5 or the acid-catalyzed/thermal desilylation of trimethylsilyl
amino derivatives.6 Photochemical treatment of tertiary amine
with C60 also leads to fulleropyrrolidines.7 Gan’s group has
explored direct reactions between amino acid esters and C60
induced by photo irradiation and ultrasonification to afford the ful-
leropyrrolidines.8 Recently, Wang’s group has reported novel ther-
mal reactions of C60 with amino acid ester hydrochlorides and
triethylamine in o-dichlorobenzene at reflux afforded fulleropyrr-
olidine derivatives.9
105 °C, and unexpectedly discovered the incorporation into two
fulleropyrrolidine derivatives. One contained a CH3CH2CH2CH moi-
ety originating from TBAC through C–N bond cleavage and the
other contained a PhCH moiety originating from toluene through
C–H bond cleavage. Furthermore, detailed investigation of these
reactions resulted in a discovery of the reactions of C60 with amino
acids and other quaternary ammonium salts. Here, we report these
novel reactions.
The reaction of C60 with amino acids and aldehydes is one of the
easiest methods to prepare some functional fullerene compounds.3
Our previous work was to synthesize some nitro fullerene deriva-
tives with this method. Initially, a mixture of C60, glycine and 2,4-
dinitrobenzaldehyde was stirred at refluxing temperature for
several days in toluene to synthesize 2-(2,4-dinitrophenyl)fullero-
pyrrolidine, and the reaction was followed by TLC. However, TLC
results revealed that the reaction did not occur. Considering the
poor solubility of glycine in toluene, the phase transfer catalysis
(PTC) of tetra-n-butylammonium chloride (TBAC) was added into
the toluene solution to improve the reaction. Unexpectedly, it
was found that C60 reacted with TBAC and glycine (1:10:8) in tol-
uene at 105 °C for 40 h to afford adducts 3a and 4a in 23% and 32%
yields, respectively (based on consumed C60) (Scheme 1). Adduct
3a possessed an n-C3H7CH moiety, which might conceivably have
originated from TBAC. To substantiate the assumption, other
quaternary ammonium salts and amino acids were used in the
reaction to see if products in which the n-C3H7CH group had been
replaced by the RCH moiety could be obtained. When C60 with qua-
ternary ammonium salts 1a–c and amino acids 2a–b were added
We have recently investigated the reactions of C60 with amino
acids and tetra-n-butylammonium chloride (TBAC) in toluene at
* Corresponding authors. Tel.: +86 816 608 9015; fax: +86 816 608 9399 (B.J.).
E-mail addresses: jinbo@swust.edu.cn (B. Jin), pengrufang@swust.edu.cn (R.-F.
Peng).
0040-4039/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tetlet.2009.07.097

B. Jin et al. / Tetrahedron Letters 50 (2009) 5640–5643
5641
toluene
toluene
+
(RCH2)4NCl +
C60
(n-C4H9)4NCl + NH2CH(CH2Ph)COOH
C60
R'NHCH2COOH
+
2
1
2a: R'=H
2b: R'=CH3
n
1a: R= -C3H7
1b: R=Me
1c: R=H
CH2Ph
CH2Ph
NH
CH2Ph
NH
+
+
NH
C3H7
C3H7
+
N R'
N R'
cis-7
trans-7
cis-8
R
4
Scheme 3. Synthesis of adducts cis/trans-7 and cis-8 by the reactions of C60 with
3
TBAC and phenylalanine in toluene.
3a: R=n-C3H7, R'=H
3b: R=n-C3H7, R'=CH3
3c: R=Me, R'=H
4a: R'=H
4b: R'=CH3
p-xylene
+ (n-C4H9)4NCl +
3d: R=Me, R'=CH3
3e: R=H, R'=CH3
C60
CH3NHCH2COOH
1a
2b
Scheme 1. Synthesis of adducts 3a–e and 4a–b by the reactions of C60 with
quaternary ammonium salts 1a–c and amino acids 2a–b in toluene.
+
N
CH3
N CH3
C3H7
into toluene and heated to 105 °C for a given time, the correspond-
ing adducts 3b–e and 4a–b were prepared (Scheme 1).
9
3b
CH3
During the work of the reaction of C60 with TBAC and alanine/
phenylalanine, it was found that the cis- and trans-2,5-disubsti-
Scheme 4. Synthesis of adducts 3b and 9 by the reactions of C60 with 1a and 2b in
p-xylene.
tuted fulleropyrrolidines were obtained.
A mixture of C60
(36.0 mg), TBAC (97.0 mg) and alanine (26.7 mg) was dissolved in
60 mL of toluene and heated to 105 °C with stirring for 48 h, and
then isolation by flash column chromatography on silica gel using
a mixture of n-hexane and toluene as eluents afforded tran-5, cis-5
and cis-6 in 49%, 25% and 13% yields, respectively, based on con-
sumed C60 (Scheme 2). When C60 (36.0 mg), TBAC (97.0 mg) and
phenylalanine (41.3 mg) were added into toluene and heated to
105 °C for 48 h, the trans-7, cis-7 and cis-8 were obtained in 35%,
32% and 21% yields, respectively (Scheme 3, based on consumed
C60).
All above-mentioned results revealed that adducts 3a–e, cis/
trans-5 and cis/trans-7 each possessed a RCH moiety, which was
changed with the different quaternary ammonium salts. So there
was no question that the RCH moiety originated from quaternary
ammonium salts through C–N bond cleavages. However, it was
very interesting that adducts 4a–b, cis-6 and cis-8 each possessed
a common PhCH moiety. Obviously, PhCH moiety did not originate
from the corresponding quaternary ammonium salts and amino
acids. The solvent toluene might have involved in the reactions
and the PhCH moiety originated from toluene. In order to confirm
the assumption, p-xylene and chlorobenzene were used in the
reaction as the solvent to substitute toluene. As desired, when a
mixture of C60 (36.0 mg), TBAC (242.0 mg) and sarcosine
(30.5 mg) was added in 20 mL p-xylene and heated to 105 °C for
3 h, the products 3b and 9 were obtained in 9% and 50% yields,
respectively (Scheme 4, based on consumed C60). When C60 with
quaternary ammonium salts 1a–c and amino acids 2a–b were
added into chlorobenzene and heated to 105 °C for a period of
time, only adducts 3a–e were synthesized in 23%, 59%, 36%, 54%
and 45% yields, respectively, as shown in Scheme 5.
The structures of products 3a–e10, 4a–b, cis/trans-5,11 cis-6,12
cis/trans-7,13 cis-814 and 910 were unambiguously confirmed by
their MS, 1H NMR, 13C NMR, FT-IR and UV–vis spectral data. The
spectral data of adducts 3d–e and 4a–b are fully consistent with
those reported previously.3,9,15 The 1H NMR spectra of compounds
3a–c and 9 each shows two doublets at d = 4.18–4.96 ppm for the
two nonequivalent methylene protons in the pyrrolidine ring.
Product 3b exhibits a singlet at d = 3.00 ppm in their 1H NMR spec-
tra for N-substituted methyl group (NCH3) in the pyrrolidine ring.
Products 3a–b each exhibits three multiplet and a triplet at
d = 1.13–2.68 in their 1H NMR spectra for 2-substituted n-C3H7
group in the pyrrolidine ring. Product 9 exhibits two singlets at
d = 2.75 and 2.31 ppm in their 1H NMR spectra for N-CH3 and Ph-
CH3 in the pyrrolidine ring. The 1H NMR spectra of cis/trans-5
and cis/trans-7 show a similar pattern, respectively, and the signals
of the pyrrolidine methine protons for the cis-isomers appear fur-
ther upfield than the corresponding signals for the trans-isomers,16
which is different with Wilson’s report that the signals for the
cis-isomers always appear further downfield than the corresponding
signals for the trans-isomers.17 The trans-5 shows a methine quartet
at d = 4.98 ppm and a methine doublet of doublets at d = 4.88 ppm,
while the corresponding methines from cis-5 appears as a quartet
at 4.76 ppm and a doublet of doublets at 4.66 ppm, respectively.
chlorobenzene
toluene
+ (RCH2)4NCl +
N R'
C60
R'NHCH2COOH
C60
(n-C4H9)4NCl + NH2CH(CH3)COOH
+
R
1
2
3
CH3
NH
CH3
NH
CH3
NH
1a: R=n-C3H7
1b: R=Me
1c: R=H
2a: R'=H
2b: R'=CH3
3a: R=n-C3H7, R'=H
3b: R=n-C3H7, R'=CH3
3c: R=Me, R'=H
3d: R=Me, R'=CH3
3e: R=H, R'=CH3
+
+
C3H7
C3H7
cis-5
trans-5
cis-6
Scheme 2. Synthesis of adducts cis/trans-5 and cis-6 by the reactions of C60 with
TBAC and alanine in toluene.
Scheme 5. Synthesis of adducts 3a–e by the reactions of C60 with quaternary
ammonium salts 1a–c and amino acids 2a–b in chlorobenzene.

5642
B. Jin et al. / Tetrahedron Letters 50 (2009) 5640–5643
amino acids and aldehydes, in which some desired aldehydes usu-
CH3
H2
CH3
H2
ally are expensive or not commercially available. This Letter pro-
vides an alternative method to make fulleropyrrolidines from
ammonium salts. Further studies aimed at the reaction mechanism
are in progress.
NH
H1
NH
H1
C3H7
Ph
cis-5
cis-6
Acknowledgements
PhH2C
PhH2C
Financial supports are provided by the National Natural Science
Foundation of China (Project No. 10576026), and the Sichuan Bu-
reau of Science and Technology (Project No. 05GG009-018-05).
H2
H2
NH
H1
NH
H1
Ph
Supplementary data
C3H7
cis-7
cis-8
Supplementary data (MS and NMR spectra of fulleropyrroli-
dines 3a–e, 4a–b, cis/trans-5, cis-6, cis/trans-7 and cis-8 and exper-
imental procedure for the preparation of all fulleropyrrolidines)
associated with this article can be found, in the online version, at
doi:10.1016/j.tetlet.2009.07.097.
Figure 1. Partial NOEs involving the hydrogens in compounds cis-5, cis-6, cis-7 and
cis-8.
Similarly the pyrrolidine methine signals for trans-7 appear as a
doublet of doublets at 5.16 ppm and a doublet of doublets at
5.00 ppm. The spectrum of cis-7 shows a methine doublet of dou-
blets at 4.89 ppm and a methine doublet of doublets at 4.60 ppm.
The 1H NMR spectra of cis-6 and cis-8 exhibit 6 signals and 9 sig-
nals, respectively. Two methine signals of cis-6 appear as a singlet
at 5.79 ppm and a quartet at 4.95 ppm, and two methine signals of
cis-8 appear as a singlet at 5.70 ppm and a doublet of doublets at
5.03 ppm.
The stereochemistry of the products cis/trans-5, cis-6, cis/trans-7
and cis-8 were also revealed by the 1H NOESY spectra. The NOEs
involving the hydrogens are indicated by the curved arrows in
Figure 1. The NOESY spectrum of cis-5 shows no correlation be-
tween H1 and methyl H, and cis-7 shows no correlation between
H1 and benzyl H. Both cis-5 and cis-7 show correlation between
H1 and H2 in their NOESY spectra. These results indicated that
cis-5 and cis-7 are cis-isomer. The NOESY spectrum of cis-6 (Fig. 2)
shows correlation between H1 and H2 but no correlation between
H1 and methyl H, and cis-8 shows correlation between H1 and H2
but no correlation between H1 and methylene H. Obviously, the
NOESY spectra indicate that cis-6 and cis-8 are cis-isomer, and
the previous Wilson’s report that cis-6 and cis-8 are trans-isomer
was incorrect.16,17
References and notes
1. (a) Taylor, R.; Walton, D. R. M. Nature 1993, 363, 685; (b) Hirsch, A. The
Chemistry of the Fullerenes; Thieme: Stuttgart, 1994; (c) Diederich, F.; Thilgen, C.
Science 1996, 271, 317; (d) Thilgen, C.; Diederich, F. Top. Curr. Chem. 1999, 199,
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Georgakilas, V.; Prato, M. Acc. Chem. Res. 2005, 38, 38; (j) Nierengarten, J. F.;
Martin, N.; Fowler, P. Fullerene Chemistry; Elsevier: SAS, Paris, 2006; (k) Martin,
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Kitaygorodskiy, A.; Ortiz, A.; Herranz, M. A.; Echegoyen, L. J. Org. Chem. 2005,
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M.; Prato, M.; Valli, L. J. Am. Chem. Soc. 2007, 129, 3148; (f) Schumacher, A. L.;
Sandanayaka, A. S. D.; Hill, J. P.; Ariga, K.; Karr, P. A.; Araki, Y.; Ito, O.; D’Souza, F.
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Chem. 2006, 71, 680; (h) Itoh, T.; Mishiro, M.; Matsumoto, K.; Hayase, S.;
Kawatsura, M.; Morimoto, M. Tetrahedron 2008, 64, 1823; (i) Baffreau, J.;
Ordronneau, L.; Leroy-Lhez, S.; Hudhomme, P. J. Org. Chem. 2008, 73, 6142; (j)
Quintiliani, M.; Kahnt, A.; Wöfle, T.; Hieringer, W.; Vázquez, P.; Göling, A.;
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3. Maggini, M.; Scorrano, G.; Prato, M. J. Am. Chem. Soc. 1993, 115, 9798.
4. Tsuge, O.; Kanemasa, S. Adv. Heterocycl. Chem. 1989, 45, 231.
In summary, a new protocol to prepare fulleropyrrolidines from
amino acids and quaternary ammonium salts has been developed.
Fulleropyrrolidines have wide application involving molecular
electronics, photochemistry, biology and materials sciences.2 The
most common method to synthesize fulleropyrrolidines involves
5. Maggini, M.; Scorrano, G.; Bianco, A.; Toniolo, C.; Sijbesma, R. P.; Wudl, F.;
Prato, M. J. Chem. Soc., Chem. Commun. 1994, 305.
6. Zhang, X.; Willems, M.; Foote, C. S. Tetrahedron Lett. 1993, 34, 8187.
7. (a) Lawson, G. E.; Kitaygorodskiy, A.; Ma, B.; Bunker, C. E.; Sun, Y.-P. J. Chem.
Soc., Chem. Commun. 1995, 2225; (b) Liou, K.-F.; Cheng, C.-H. Chem. Commun.
1996, 1423; (c) Wu, S.-H.; Zhang, D.-W.; Wang, G.-W.; Shu, L.-H.; Wu, H.-M.;
Xu, J.-F.; Lao, X.-F. Synth. Commun. 1997, 27, 2289; (d) Gan, L.-B.; Jiang, J.-F.;
Zhang, W.; Su, Y.; Shi, Y.; Huang, C.-H.; Pan, J.-Q.; Lu, M.-J.; Wu, Y. J. Org. Chem.
1998, 63, 4240; (e) Lawson, G. E.; Kitaygorodskiy, A.; Sun, Y.-P. J. Org. Chem.
1999, 64, 5913; (f) Guo, L.-W.; Gao, X.; Zhang, D.-W.; Wu, S.-H.; Wu, H.-M.; Li,
Y.-J.; Wilson, S. R.; Richardson, C. F.; Schuster, D. I. J. Org.Chem. 2000, 65, 3804;
(g) Nakamura, Y.; Suzuki, M.; Okawa, K.; Konno, T.; Nishimura, J. J. Org. Chem.
2005, 70, 8472.
8. (a) Gan, L.-B.; Zhou, D.-J.; Luo, C.-P.; Tan, H.-S.; Huang, C.-H.; Lu, M.-J.; Pan, J.-Q.;
Wu, Y. J. Org. Chem. 1996, 61, 1954; (b) Zhang, X.; Gan, L.-B.; Huang, S.-H.; Shi,
Y.-R. J. Org. Chem. 2004, 69, 5800.
9. Wang, G.-W.; Chen, X.-P.; Cheng, X. Chem. Eur. J. 2006, 12, 7246.
10. 2-Propylfulleropyrrolidine (3a): UV–vis (CHCl3) kmax: 257 (s), 310 (m), 431 (w)
nm; 1H NMR (CS2/CDCl3, 600 MHz) d: 4.95 (d, J = 11.7 Hz, 1H), 4.71 (d,
J = 11.9 Hz, 1H), 4.68 (dd, J = 10.4, 3.0 Hz, 1H), 2.62–2.68 (m, 1H), 2.05–2.18 (m,
2H), 1.89–1.96 (m, 1H), 1.21 (t, J = 7.4 Hz, 3H) ppm; 13C NMR (CS2/CDCl3,
150 MHz) d: 156.04, 154.43, 154.40, 153.02, 147.10 (2C), 146.60, 146.50,
146.38, 146.34, 146.31, 146.24 (2C), 146.10, 146.06, 146.01 (2C), 145.73,
145.39 (4C), 145.35 (2C), 145.30, 145.23, 144.63, 144.50, 144.38 (2C), 143.30,
143.22, 143.13, 142.75 (3C), 142.41, 142.31, 142.28, 142.25, 142.12 (2C),
141.97, 141.87, 141.81, 140.39, 140.27, 140.22, 139.93, 136.48, 135.83, 135.78,
135.56, 78.63 (sp3-C of C60), 75.70 (sp3-C of C60), 74.72 (CH), 63.14 (CH), 36.17
(CH2CH2CH3), 22.06 (CH2CH2CH3), 14.70 (CH2CH2CH3) ppm; IR (KBr) m: 2957,
2923, 2864, 1628, 1533, 1457, 1401, 1184, 1098, 569, 526 cmÀ1; MS (MAIDI-
TOF) m/z: 805 [M]+, 720 [C60]+. N-Methyl-2-propylfulleropyrrolidine (3b): UV–vis
(CHCl3) kmax: 257 (s), 309 (m), 431 (w) nm; 1H NMR (CS2/CDCl3, 300 MHz) d:
Figure 2. The NOESY spectrum of cis-6.

B. Jin et al. / Tetrahedron Letters 50 (2009) 5640–5643
5643
4.80 (d, J = 9.6 Hz, 1H), 4.18 (d, J = 9.7 Hz, 1H), 3.92 (t, J = 4.8 Hz, 1H), 3.00 (s,
3H), 2.46–2.57 (m, 1H), 2.29–2.42 (m, 1H), 1.90–2.04 (m, 2H), 1.13 (t, J = 7.3 Hz,
3H) ppm; 13C NMR (CS2/CDCl3, 75 MHz) d: 156.25, 154.21, 154.14, 153.21,
147.01, 146.97, 146.56, 146.32, 146.14, 146.09, 146.09, 145.95 (2C), 145.88,
145.83, 145.76, 145.74, 145.60, 145.34, 145.24 (3C), 145.14, 145.06 (3C),
144.98, 144.55, 144.39, 144.20, 144.15, 142.99, 142.86, 142.49, 142.46 (2C),
142.43, 141.97 (3C), 141.90, 141.86, 141.64, 141.53, 141.48, 140.10, 140.03,
139.62, 139.45, 137.04, 136.10, 135.66, 135.33, 77.87 (CH), 76.06 (sp3-C of C60),
70.24 (CH), 69.89 (sp3-C of C60), 39.71 (NCH3), 33.32 (CH2CH2CH3), 21.07
78.37 (sp3-C of C60), 76.48 (sp3-C of C60), 76.02 (CH), 67.11 (CH), 18.39 (CH3)
ppm; IR (KBr) : 2961, 2923, 2867, 2808, 1493, 1453, 1183, 1153, 1095, 1030,
m
763, 698, 571, 526 cmÀ1; MS (MAIDI-TOF) m/z: 853 [M]+, 720 [C60]+.
13. cis-2-Benzyl-5-propylfulleropyrrolidine (cis-7): UV–vis (CHCl3) kmax: 257 (s),
308 (m), 431 (w) nm; 1H NMR (CS2/CDCl3, 300 MHz) d: 7.53 (d, J = 7.3 Hz, 2H),
7.38–7.47 (m, 2H), 7.29–7.37 (m, 1H), 4.89 (dd, J = 10.7, 2.7 Hz 1H), 4.60 (dd,
J = 10.3, 2.8 Hz, 1H), 4.00 (dd, J = 13.8, 2.7 Hz, 1H), 3.38 (dd, J = 13.2, 10.7 Hz,
1H), 2.53–2.64 (m, 1H), 2.17–2.09 (m, 1H), 1.88–1.95 (m, 1H), 1.73–1.82 (m,
1H), 1.16 (t, J = 7.3 Hz, 3H) ppm; 13C NMR (CS2/CDCl3, 75 MHz) d: 154.07,
153.79, 153.28, 152.85, 146.86 (2C), 146.40, 146.35, 146.21, 146.17, 146.10,
146.07, 145.94, 145.81 (2C), 145.69, 145.49, 145.20 (2C), 145.16, 145.10,
145.07, 144.96, 144.93, 144.40, 144.33, 144.07 (2C), 143.01, 142.81, 142.48
(2C), 142.45 (2C), 142.30, 142.24, 142.00, 141.93, 141.91, 141.86, 141.73,
141.70, 141.49 (2C), 139.92, 139.89, 139.60, 139.54, 138.79 (2C), 138.60,
136.81, 136.42, 135.70, 135.52, 129.05 (2C), 128.93, 128.68 (2C), 126.70, 77.65
(sp3-C of C60), 77.30 (sp3-C of C60), 73.05 (CH), 71.99 (CH), 39.65 (CHCH2Ph),
(CH2CH2CH3), 14.92 (CH2CH2CH3) ppm; IR (KBr) m: 2951, 2864, 2776, 1630,
1536, 1458, 1425, 1342, 1184, 1158, 1114, 1026, 571, 526 cmÀ1; MS (MAIDI-
TOF) m/z: 819 [M]+, 720 [C60]+. 2-Methylfulleropyrrolidine (3c): UV–vis (CHCl3)
kmax: 257 (s), 311 (s), 431 (w) nm; 1H NMR (CS2/CDCl3, 600 MHz) d: 4.96 (d,
J = 12.0 Hz, 1H), 4.81 (q, J = 6.6 Hz, 1H), 4.75 (d, J = 12.0 Hz, 1H), 2.11 (d,
J = 6.6 Hz, 3H) ppm; IR (KBr) m: 3415, 2966, 2918, 2848, 1637.6, 1617.7, 1400,
1261, 1185, 1090, 1028, 805, 768, 619, 570, 561, 552, 526 cmÀ1; MS (MAIDI-
TOF) m/z: 777 [M]+, 720 [C60]+. N-Methyl-2-(4-methylphenyl)fulleropyrrolidine
(9): UV–vis (CHCl3) kmax: 259 (s), 310 (s), 430 (w) nm; 1H NMR (CS2/CDCl3,
600 MHz) d: 7.60 (d, J = 7.8 Hz, 2H), 7.15 (d, J = 7.8 Hz, 2H), 4.92 (d, J = 9.6 Hz,
1H), 4.84 (s, 1H), 4.20 (d, J = 9.0 Hz, 1H), 2.75 (s, 3H), 2.31 (s, 3H) ppm; MS
(MAIDI-TOF) m/z: 867 [M]+, 720 [C60]+.
35.69 (CH2CH2CH3), 21.87 (CH2CH2CH3), 14.60 (CH2CH2CH3) ppm; IR (KBr) m:
2956, 2917, 2849, 1637, 1493, 1472, 1463, 1400, 1262, 1179, 1126, 949, 889,
807, 777, 765, 728, 719, 693, 615, 574, 561, 526 cmÀ1; MS (MAIDI-TOF) m/z:
896 [M+1]+, 720 [C60]+. trans-2-benzyl-5-propylfulleropyrrolidine (trans-7):
UV–vis (CHCl3) kmax: 257 (s), 307 (m), 432 (w) nm; 1H NMR (CS2/CDCl3,
300 MHz) d: 7.52 (d, J = 7.4 Hz, 2H), 7.40 (t, J = 7.6 Hz, 2H), 7.27 (t, J = 7.2 Hz,
1H), 5.16 (dd, J = 10.9, 3.9 Hz, 1H), 5.00 (dd, J = 10.8, 3.3 Hz, 1H), 3.77 (dd,
J = 14.0, 4.0 Hz, 1H), 3.64 (dd, J = 13.8, 10.9 Hz, 1H), 2.44–2.55 (m, 1H), 2.20–
2.28 (m, 1H), 1.87–1.98 (m, 1H), 1.74–1.86 (m, 1H), 1.18 (t, J = 7.3 Hz, 3H) ppm;
13C NMR (CS2/CDCl3, 75 MHz) d: 155.92, 155.65, 153.14, 152.87, 146.94, 146.31
(2C), 146.07 (3C), 145.96, 145.84 (2C), 145.60, 145.42 (2C), 145.18 (3C), 145.06
(2C), 144.38 (2C), 144.20, 143.05, 142.55 (2C), 142.51 (2C), 142.35, 142.26,
141.99 (3C), 141.75, 141.69, 141.65, 140.08, 139.73, 139.04, 136.61, 136.38,
135.34, 135.15, 129.27, 128.59, 126.67, 78.09 (sp3-C of C60), 77.88 (sp3-C of
C60), 71.89 (CH), 70.32 (CH), 40.73 (CHCH2Ph), 36.62 (CH2CH2CH3), 21.65
11. trans-2-Methyl-5-propylfulleropyrrolidine (trans-5): UV–vis (CHCl3) kmax: 260
(s), 310 (m), 431 (w) nm; 1H NMR (CS2/CDCl3, 600 MHz) d: 4.98 (q, J = 6.6 Hz,
1H), 4.88 (dd, J = 11.4, 3.6 Hz, 1H), 3.11 (s, 1H), 2.35–2.40 (m, 1H), 2.28–2.33
(m, 1H), 2.01 (d, J = 6.6 Hz, 3H), 1.99–2.06 (m, 1H), 1.76–1.83 (m, 1H), 1.61 (t,
J = 7.8 Hz, 3H) ppm; 13C NMR (CS2/CDCl3, 100 MHz) d: 156.37, 155.80, 153.17,
153.00, 146.93, 146.34 (3C), 146.13 (2C), 146.09, 145.86 (3C), 145.67, 145.38,
145.19 (2C), 145.09, 145.00 (2C), 144.40, 144.37, 144.25 (3C), 144.07, 143.08,
142.55 (3C), 142.48, 142.42 (2C), 142.08, 142.02 (2C), 141.77, 141.72 (2C),
141.66, 140.14, 140.08, 139.86, 139.76, 139.50, 136.34, 134.89, 79.14 (sp3-C of
C60), 79.08 (sp3-C of C60), 71.67 (CH), 66.65 (CH), 37.10 (CH2CH2CH3), 21.64
(CH2CH2CH3), 19.91 (CHCH3), 14.36 (CH2CH2CH3) ppm; IR (KBr)
m
: 2955, 2922,
(CH2CH2CH3), 14.42 (CH2CH2CH3) ppm; IR (KBr) m: 3025, 2953, 2922, 2863,
2862, 1630, 1452, 1491, 1184, 1152, 1092, 1031, 774, 565, 527 cmÀ1; MS
(MAIDI-TOF) m/z: 819 [M]+, 720 [C60]+. cis-2-Methyl-5-propylfulleropyrroli-
dine (cis-5): UV–vis (CHCl3) kmax: 257 (s), 309 (m), 431 (w) nm; 1H NMR (CS2/
CDCl3, 600 MHz) d: 4.76 (q, J = 6.6 Hz, 1H), 4.66 (dd, J = 10.8, 2.4 Hz, 1H), 2.56–
2.62 (m, 1H), 1.98–2.08 (m, 2H), 2.02 (d, J = 6.6 Hz, 3H), 1.82–1.88 (m, 1H), 1.16
(t, J = 7.2 Hz, 3H) ppm; 13C NMR (CS2/CDCl3, 150 MHz) d: 154.50, 154.32,
153.63, 153.27, 147.06 (2C), 146.64, 146.48, 146.40, 146.37, 146.34, 146.21
(2C), 146.06, 145.97, 145.69, 145.39 (3C), 145.36, 145.22, 145.21, 144.59 (2C),
144.35, 144.34, 143.32, 143.12, 142.80, 142.78 (2C), 142.73, 142.72, 142.30,
142.29, 142.24, 142.12, 142.02, 142.00, 141.82, 141.79, 140.34, 140.20, 140.01,
139.88, 136.59, 136.34, 135.77, 135.69, 79.79 (sp3-C of C60), 79.62 (sp3-C of
C60), 73.58 (CH), 68.78 (CH), 35.93 (CH2CH2CH3), 22.38 (CH2CH2CH3), 18.03
1633, 1509, 1455, 1424, 1219, 1184, 1149, 1032, 729, 697, 568, 526 cmÀ1; MS
(MAIDI-TOF) m/z: 895 [M]+, 720 [C60]+.
14. cis-2-Benzyl-5-phenylfulleropyrrolidine (cis-8): UV–vis (CHCl3) kmax: 257 (s),
312 (m), 430 (w) nm; 1H NMR (CS2/CDCl3, 300 MHz) d: 7.83 (d, J = 7.2 Hz, 2H),
7.58 (d, J = 7.3 Hz, 2H), 7.44 (t, J = 7.3 Hz, 2H), 7.26–7.40 (m, 4H), 5.70 (s, 1H),
5.03 (dd, J = 11.1, 2.5 Hz 1H), 4.04 (dd, J = 13.1, 2.4 Hz, 1H), 3.52 (dd, J = 13.1,
11.2 Hz, 1H), 2.88 (s, NH) ppm; 13C NMR (CS2/CDCl3, 75 MHz) d: 153.33,
153.16, 153.08, 152.93, 146.93, 146.89, 146.46 (2C), 146.08, 145.98, 145.95
(2C), 145.89 (2C), 145.81, 145.79, 145.63, 145.60, 145.42, 145.33, 145.18 (2C),
145.00, 144.98, 144.89 (2C), 144.39, 144.33, 144.08, 144.03, 142.83, 142.73,
142.42, 142.37 (2C), 142.31, 142.01, 141.91 (2C), 141.88 (2C), 141.78 (2C),
141.75, 141.67, 141.60, 141.40, 141.27, 139.94, 139.69, 139.47, 139.30, 138.86
(2C), 137.39 (2C), 137.30, 136.54, 135.96, 135.55, 128.97 (2C), 128.89 (2C),
128.35, 128.23 (2C), 128.19 (2C), 126.83, 77.20 (sp3-C of C60), 74.83 (CH), 74.37
(CHCH3), 14.91 (CH2CH2CH3) ppm; IR (KBr) m: 2956, 2866, 1628, 1425, 1184,
1147, 1090, 1029, 572, 526 cmÀ1; MS (MAIDI-TOF) m/z: 819 [M]+, 720 [C60]+.
12. cis-2-Methyl-5-phenylfulleropyrrolidine (cis-6): UV–vis (CHCl3) kmax: 257 (s),
310 (m), 430 (w) nm; 1H NMR (CS2/CDCl3, 600 MHz) d: 7.75 (d, J = 7.2 Hz, 2H),
7.35 (t, J = 7.2 Hz, 2H), 7.27 (t, J = 7.2 Hz, 1H), 5.79 (s, 1H), 4.95 (q, J = 6.6 Hz,
1H), 2.12 (d, J = 6.6 Hz, 3H) ppm; 13C NMR (CS2/CDCl3, 150 MHz) d: 153.90,
153.64, 147.18, 146.85, 146.63, 146.39, 146.35, 146.26, 146.14, 146.10, 145.93,
145.71, 145.55, 145.48, 145.35, 145.32, 145.21, 144.64, 144.38, 143.23, 143.07,
142.76, 142.72, 142.65, 142.55, 142.38, 142.28, 142.22, 142.13, 142.11, 142.08,
142.04, 141.94, 141.75, 141.60, 140.32, 140.01, 139.85, 139.59, 137.49, 137.31,
136.64, 135.97, 135.89, 128.84 (2C, aryl C), 128.56 (aryl C), 128.34 (2C, aryl C),
(sp3-C of C60), 72.05 (CH), 39.80 (CHCH2Ph) ppm; IR (KBr)
m: 3026, 2849, 2820,
1633, 1602, 1494, 1462, 1452, 1400, 1260, 1183, 1097, 1027, 770, 745, 717,
697, 613, 600, 573, 563, 544, 526 cmÀ1; MS (MAIDI-TOF) m/z: 929 [M]+, 720
[C60]+.
15. (a) Zhou, D.-J.; Gan, L.-B.; Tan, H.-S.; Luo, C.-P.; Huang, C.-H.; Pan, J.-Q.; Lu, M.-
J.; Wu, Y. Chin. Chem. Lett. 1995, 6, 1033; (b) D’Souza, F.; Deviprasad, G. R.;
Rahman, M. S.; Choi, J.-P. Inorg. Chem. 1999, 38, 2157.
16. Wang, G.-W.; Tian, Z.-G. Tetrahedron Lett. 2009, 50, 3860.
17. Wilson, S.-R.; Wang, Y.-H.; Cao, J.-R.; Tan, X.-F. Tetrahedron Lett. 1996, 37, 775.