Cycloaddition of diazoacetates to C60 fullerene catalysed by Pd complexes

Article abstract of DOI:10.1007/s11172-010-0339-1

An efficient catalytic method of the cycloaddition to C₆₀ fullerene of the diazoacetates, containing substituents of diverse structures in ester groups, in the presence of a Pd-based three-component catalyst was developed. An influence of nature and the structure of substituent in the ester group on the activity of diazoacetates in the reaction with C₆₀ was studied. Yields of respective cycloadducts were determined.

Full text of DOI:10.1007/s11172-010-0339-1

Russian Chemical Bulletin, International Edition, Vol. 59, No. 10, pp. 1959—1963, October, 2010
1959
Cycloaddition of diazoacetates to C60 fullerene catalysed by Pd complexes
A. R. Tuktarov, A. R. Akhmetov, L. L. Khasanova, L. M. Khalilov, and U. M. Dzhemilev
Institute of Petroleum Chemistry and Catalysis, Russian Academy of Sciences,
141 prosp. Oktyabrya, 450075 Ufa, Russian Federation.
Fax: +7 (347) 284 2750. Eꢀmail: ink@anrb.ru
An efficient catalytic method of the cycloaddition to C60 fullerene of the diazoacetates,
containing substituents of diverse structures in ester groups, in the presence of a Pdꢀbased
threeꢀcomponent catalyst was developed. An influence of nature and the structure of substiꢀ
tuent in the ester group on the activity of diazoacetates in the reaction with C60 was studied.
Yields of respective cycloadducts were determined.
Key words: metallocomplex catalysis, C60 fullerene, diazoacetates, cycloaddition.
An interest in carboxy derivatives of methanofullerenes
is caused by a possibility of obtaining of promising prepaꢀ
rations for medicine and agriculture on their base.1—5
However, a synthesis of these C60 derivatives containing
substituents in the ester group consists in multiꢀstage conꢀ
version of carboxymethanofullerene which results in low
yields of the target products.1,3,6—9
Recently, an efficient catalytic method of cycloaddiꢀ
tion of diazoacetic ester and αꢀsubstituted ethyl diazoaceꢀ
tates to the C60 fullerene using the threeꢀcomponent cataꢀ
lyst Pd(acac)2—PPh3—Et3Al (20 mol.%) was suggestꢀ
ed.10,11 As it is noted, by a ratio of the starting components
of catalytic system and the nature of the substituent in
αꢀposition to the diazo group of the initial diazoacetate, it
is possible to definitely regulate a direction of the cycloadꢀ
dition and to selectively obtain both methanofullerenes
and homofullerenes.
In order to develop our earlier elaborated10,11 method
of the catalytic cycloaddition of the diazoacetates to the
C60 fullerene under the action of catalysts on a basis of
lowꢀvalent Pd complexes, as well as to investigate the inꢀ
fluence of the structure of substituent in the ester group of
diazoacetate on the direction and the structural selectivity
of the reaction of the latters with the fullerene C60, we
studied the cycloaddition of diazoacetates with alkyl,
cycloalkyl, allyl, and steroid substituents to the fullerene
the threeꢀcomponent catalyst Pd(acac)2—PPh3—Et3Al
(components molar ratio is 1 : 2 : 4, respectively) is used.
During the cycloaddition using the components molar raꢀ
tio of this catalytic system equal to 1 : 4 : 4, only the methꢀ
anofullerenes were formed regardless of the substituent
structure in the diazo compound. Therefore, all the folꢀ
lowing experiments were carried out using the catalytic
system Pd(acac)2—PPh3—Et3Al (1 : 2 : 4) with a purpose
of more detailed study of the influence of the structure of
initial diazoacetates on the composition of the cycloꢀ
adducts formed.
In a reaction of isopropyl diazoacetate with the
fullerene C60 (molar ratio 5 : 1) in the presence of 20 mol.%
of threeꢀcomponent catalyst Pd(acac)2—PPh3—Et3Al
(1 : 2 : 4) in 1,2ꢀdichlorobenzene at 80 °C, in 1 h a mixture
of [6,6]ꢀclosed (1) and two stereoisomeric [5,6]ꢀopen (2, 3)
adducts of C60 with a total yield* ~70% is formed (Scheme 1).
An increasing of the reaction duration to 2 h does not
result in a noticeable increasing of the total yield (~76%)
of the target cycloadducts. At a higher concentration of
organophosphorous ligand in the threeꢀcomponent cataꢀ
lytic system (components ratio 1 : 4 : 4), we managed to
direct the mentioned reaction to the selective formation of
the respective methanofullerene 1 in a ~72% yield.
Using a method of semiꢀpreparative HPLC we isolatꢀ
ed a mixture of the cycloadducts of mono addition 1—3.
We could not separate the compounds 1—3. This was
caused by the close physicalꢀchemical constants and poꢀ
larity of the obtained adducts, which do not allow their
separation in individual forms by chromatography. Oneꢀ
(1H and 13C) and twoꢀdimensional (COSY, HSQC,
HMBC) NMR experiments showed that the mixture of
C
60 catalysed by Pd(acac)2—PPh3—Et3Al (1 : 2 : 4)
Results and Discussion
It was earlier shown,11 that the influence of nature and
substituent structure in the αꢀsubstituted ethyl diazoaceꢀ
tates on the selectivity of formation of homoꢀ and methanoꢀ
fullerenes in the reaction with C60 is most evident when
* Hereafter the yields are based on the starting fullerene C60
.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1909—1913, October, 2010.
1066ꢀ5285/10/5910ꢀ1959 © 2010 Springer Science+Business Media, Inc.

1960
Russ.Chem.Bull., Int.Ed., Vol. 59, No. 10, October, 2010
Tuktarov et al.
Scheme 1
[6,6]ꢀclosed (1) and stereoisomeric [5,6]ꢀopen (2, 3)
ized (δC 70.84) and sp2ꢀhybridized (δC 148.36) carbon atꢀ
oms of the fullerene sphere in the αꢀ and βꢀpositions,
and also with the carbon atom of carbonyl group (δC 165.43).
Lowꢀfield and highꢀfield signals of the hydrogen atoms at
the bridge carbon atoms in the [5,6]ꢀopen adducts 2 and 3
(δH 7.40 and 3.75) have four crossꢀpeaks, each one with
bridgeꢀhead carbon atoms (δC 131.16 and 133.46) and the
carbon atoms of the fullerene sphere (δC 136.64, 142.87,
and 135.22, 144.07) in βꢀposition, and also with the carꢀ
bonyl carbon atoms (δC 165.23 and 169.09).
monoadducts of the fullerene was formed.
1
On the basis of integral curves of signals in H NMR
spectrum of the compounds 1—3, a ratio of the cycloꢀ
adducts was found: 1 : 2 : 3 = 6 : 5 : 4. Singlet signals
(δH 4.74, 7.40, and 3.75) by analogy with the earlier obꢀ
tained data10,11 were assigned to hydrogen atoms at a bridge
carbon atom of the compounds 1—3, respectively. The
1H NMR spectrum of the compounds 1—3 mixture also
has three sets of doublets (δH 1.54 (J = 6.0 Hz), 1.36
(J = 6.0 Hz), and 1.49 (J = 6.0 Hz)) and septets (δH 5.38
(J = 6.0 Hz), 5.12 (J = 6.0 Hz) and 5.47 (J = 6.0 Hz)),
pertaining to the hydrogen atoms of the isopropyl group of
the ester fragment. By analogy with the earlier published
data10 for the adducts of cycloaddition of the diazoacetic
ester to the fullerene C60 this confirms the formation of
[6,6]ꢀclosed methanofullerene 1 and two stereoisomeric
[5,6]ꢀopen fulleroids 2 and 3 in which the hydrogen atom
is arranged at the bridge carbon atom above a plane of
fiveꢀ and sixꢀmembered fragment of the C60 molecule,
respectively. In 13C NMR spectrum of the mixture of adꢀ
ducts 1—3, ten signals in a high field (δC 21.82, 22.03,
22.14, 39.61, 52.10, 54.45, 69.83, 70.36, 70.55, and 70.84)
were observed. The analysis of HSQC spectra of the mixꢀ
ture of compounds 1—3 showed that the signals at δC 22.14
and 70.36 are assigned to carbon atoms of the isopropyl
group, and the signal at δC 39.61 is assigned to the bridge
carbon atom of the compound 1. In the same way, the
signals at δC 22.03 and 69.83 and δC 21.82 and 70.55 are
assigned to the carbon atoms of the two isopropyl groups,
and the signals at δC 52.10 and 54.45 are assigned to the
bridge carbon atoms of the adducts 2 and 3, respectively.
In the HMBC experiment for the mixture of isomers
1—3 (Fig. 1) we observed crossꢀpeaks of the hydrogen
atoms at the respective bridge carbon atoms with fullerene
carbon atoms in αꢀ and βꢀsurrounding. Thus, typical of
the [6,6]ꢀclosed adduct 1 are interactions of the hydrogen
atom at the bridge carbon atom (δH 4.74) with sp3ꢀhybridꢀ
The formation of the mixture of [6,6]ꢀclosed and two
stereoisomeric [5,6]ꢀopen adducts with a composition
C65H8O2 was also confirmed by MALDI TOF massꢀspecꢀ
trometry. Experiments were carried out in a linear (TOF)
Fig. 1. Distant interactions of the hydrogen atom at the bridge
carbon atom with C atoms of the fullerene cage in the HMBC
experiments.

Cycloaddition of diazoacetates to [60]fullerene
Russ.Chem.Bull., Int.Ed., Vol. 59, No. 10, October, 2010
1961
Table 1. Influence of structure of substituent (R) in ester
group of initial diazo compound on yields and ratios of target
cycloadducts 4—6
and reflector (TOF/TOF) modes with a registration of
positive and negative ions, which showed the presence of a
molecular ion with m/z 820.787 (Mcalc = 820.758), and
fragment ions with m/z 733.766 [C60CH]+ (Mcalc
=
R
Total yield of cycloadducts
Ratio of isomers
733.662) and m/z 778.783 [C60CHCOO]+ (Mcalc = 778.678).
In order to study the influence of a size and the strucꢀ
ture of the substituent in the ester group of the initial diazo
compound on the yield and the selectivity of the formaꢀ
tion of homoꢀ and methanofullerenes, tertꢀbutyl, cycloꢀ
hexyl, allyl, and benzyl diazoacetates (Scheme 2, Cy is
cyclohexyl) were involved into the reaction with C60. It
was found that under the conditions we elaborated (80 °C,
1 h, Pd(acac)2—PPh3—Et3Al (1 : 2 : 4)), C60 reacts with
the mentioned diazo compounds (molar ratio 1 : 5) to form
respective monoadducts 4a—d, 5b,c, 6b—d. Yields and
ratios of the cycloadducts 4—6 are presented in Table 1.
1H and 13C NMR spectra of the compounds 4b—d, 5b,c,
6b—d point that during the reactions stated above, the
mixture of [6,6]ꢀclosed and [5,6]ꢀopen adducts of fullerene
is also formed. However, the absence of the characteristic
signals of the bridge carbon atom (δC 52.10) and bonded
4—6 (%)
4 : 5 : 6 (%)
But
Cy
All
Bn
46
58
48
45
1 : 0 : 0
2 : 2 : 3
8 : 4 : 5
3 : 0 : 2
Note. Reaction conditions: 80 °C, 1 h, Pd(acac)2—PPh3—Et3Al
(1 : 2 : 4), solvent is 1,2ꢀdichlorobenzene.
substituents of diverse structures in the ester group to the
fullerene C60, we accomplished oneꢀstage synthesis (a yield
~50%) of a methanofullerene 7 containing a cholesterylꢀ
oxycarbonyl group in the methane fragment (Scheme 3).
It was also found that in the mentioned reaction, the stereoꢀ
isomeric [5,6]ꢀopen adducts were not formed. According
to the literature data,3,4,7,8,12 the synthesis of these carboxy
derivatives of the methanofullerenes whose ester group
contain bulk substituents, can be performed in five stages.
The structure of the cycloadduct 7 was reliably identiꢀ
fied by the methods of NMR, UV, and IR spectroscopy,
as well as a high resolution massꢀspectrometry.
Thus, in the 13C NMR spectrum, the signals of sp3ꢀ
hybridized carbon atoms of the fullerene cage (δC 70.87)
and a methine carbon atom (δC 39.83) (δH 4.74 in the
1H NMR spectrum) definitely point at the formation of
the cyclopropane fragment of methanofullerene 7 bonded
with the cholesterol residue through the carboxyl group
(δC 164.79). The cholesterol fragment of the molecule is
represented in the 13C NMR spectrum by twenty four reꢀ
solved signals in the high field, which is typical of sp3ꢀ
hybridized carbon atoms of the cholesterol (δC 12—57),
1
with it hydrogen atom (δH 7.40) in the H and 13C NMR
spectra of the mixture of compounds 4d and 6d obtained
by reaction of the C60 fullerene with benzyl diazoacetate
shows that the stereoisomeric homofullerene, in which
the ester group is arranged above the plane of the sixꢀ
membered fragment of the C60 molecule, is not formed
under these conditions. At the same time, as we have found,
in the reaction of the fullerene C60 with tertꢀbutyl diazoacꢀ
etate in the presence of the threeꢀcomponent catalytic
system Pd(acac)2—PPh3—Et3Al (1 : 2 : 4), only the methꢀ
anofullerene 4а is formed, which is apparently explained
by a spatially encumbered substituent in the ester group of
the starting diazo compound.
In order to extend the scope of the method developed
by us for the catalytic cycloaddition of the diazoacetates with
Scheme 2
R = But (4a); Cy (4b, 5b, 6b); All (4c, 5c, 6c); Bn (4d, 6d)

1962
Russ.Chem.Bull., Int.Ed., Vol. 59, No. 10, October, 2010
Tuktarov et al.
Scheme 3
Massꢀspectra were registered on a device MALDI TOF/TOF
AutoflexꢀIII Bruker without using a matrix in the linear and
reflector modes with the registration of the positive and negative
ions. Samples for an application on a metallic target were
dissolved in toluene.
Cycloaddition of the diazoacetates to the fullerene C60 (general
procedure). Into a glass reactor, Pd(acac)2 (0.00278 mmol)
in 1,2ꢀdichlorobenzene (0.2 mL), PPh3 (0.00556 mmol) in
1,2ꢀdichlorobenzene (0.21 mL) were loaded, the mixture was
cooled to –5—0 °C. Et3Al (0.01112 mmol) in toluene (0.1 mL)
was added under a dry argon current and stirring, the color
changed from lightꢀyellow to lightꢀbrown. To the obtained cataꢀ
lyst, fullerene C60 (0.0139 mmol) in 1,2ꢀdichlorobenzene (1 mL)
was added at ~20 °C, the solution became deepꢀgreen. The mixꢀ
ture was heated to 80 °C, the diazo compound (0.0695 mmol)
in 1,2ꢀdichlorobenzene (1 mL) was added dropwise during
2—3 min, the mixture was stirred for 1 h at the respective temꢀ
perature. The reaction mixture was cooled to ~20 °С, treated
with aqueous HCl, then 7 mL toluene was added, an organic
layer passed through a column with small amount of silica gel.
The reaction products and the starting fullerene C60 were sepaꢀ
rated by the semiꢀpreparative HPLC, eluent was toluene. A comꢀ
pound 4a was characterised in comparison with the literaꢀ
ture data.13
1´ꢀIsopropyloxycarbonylꢀ(C60ꢀIh)[5,6]fullereno[2´,3´:1,9]ꢀ
cyclopropane (1). IR, ν/cm–1: 540, 820, 1040, 1110, 1270, 1670.
UV (CHCl3), λmax/nm: 260, 327, 424. 1H NMR (δ): 1.54 (d, 6 H,
2 Me, J = 6.0 Hz); 4.74 (s, 1 H, CH); 5.38 (sept, 1 H, CH,
J = 6.0 Hz). 13C NMR (δ): 22.14, 39.61, 70.36, 70.84 (sp3),
136.64, 140.67, 140.99, 141.23, 142.00, 142.18, 142.32, 142.50,
142.87, 143.04, 143.11, 143.13, 143.40, 143.78, 144.02, 144.47,
144.68, 144.72, 144.92, 145.13, 145.23, 145.28, 145.63, 145.83,
148.36, 165.43. MS (MALDIꢀTOF), m/z: found: 820.787; for
С65Н8О2 calculated: 820.758.
1´aꢀIsopropyloxycarbonylꢀ1´aꢀcarbaꢀ1´(2´)aꢀhomo(C60ꢀIh)ꢀ
[5,6]fullerene (stereoisomer 2). 1H NMR (δ): 1.36 (d, 6 H, 2 Me,
J = 6.0 Hz); 5.12 (sept, 1 H, CH, J = 6.0 Hz); 7.40 (s, 1 H, CH).
13C NMR (δ): 22.03, 52.10, 69.83, 131.16, 134.13, 136.64, 138.76,
138.82, 140.82, 142.00, 142.33, 142.36, 142.87, 143.56, 143.87,
144.35, 144.46, 144.72, 144.92, 145.03, 145.63, 147.74, 165.23.
1´aꢀIsopropyloxycarbonylꢀ1´aꢀcarbaꢀ1´(2´)aꢀhomo(C60ꢀIh)ꢀ
[5,6]fullerene (stereoisomer 3). 1H NMR (δ): 1.49 (d, 6 H, 2 Me,
J = 6.0 Hz); 3.75 (s, 1 H, CH); 5.47 (sept, 1 H, CH, J = 6.0 Hz).
13C NMR (δ): 21.82, 54.45, 70.55, 133.46, 134.04, 135.22, 137.87,
138.07, 138.30, 138.53, 138.54, 140.23, 141.81, 142.00, 142.21,
142.45, 142.63, 142.87, 143.05, 143.09, 143.28, 143.31, 143.42,
143.69, 143.78, 144.07, 144.68, 144.72, 144.92, 145.21, 145.28,
169.09.
1´ꢀCyclohexyloxycarbonylꢀ(C60ꢀIh)[5,6]fullereno[2´,3´:1,9]ꢀ
cyclopropane (4b). IR, ν/cm–1: 570, 1040, 1060, 1220, 1480,
1660, 1750. UV (CHCl3), λmax/nm: 262, 326, 427. 1H NMR (δ):
1.20—2.20 (m, 10 H, 5 CH2); 4.75 (s, 1 H, CH); 5.05—5.16
(m, 1 H, CH). 13C NMR (δ): 24.27, 25.93, 32.15, 39.79, 70.91
(sp3), 75.25, 136.64, 140.69, 140.99, 141.25, 142.02, 142.19,
142.31, 142.50, 142.88, 143.03, 143.13, 143.40, 143.79, 144.03,
144.47, 144.69, 144.72, 144.93, 145.16, 145.23, 145.28, 145.63,
145.87, 148.36, 164.80. MS (MALDIꢀTOF), m/z: found: 860.770;
for С68Н12О2 calculated: 860.822.
i. Pd(acac)2—PPh3—Et3Al (1 : 2 : 4), 80 °C, 1 h.
and also by a signal of "carbonyl" carbon atom (δC 76.40) and
two signals of the carbon atoms at a double bond (δC 123.66
and 139.09). For the fullerene cage of the molecule, 17 signals
in a region of sp2ꢀhybridized carbon atoms are observed,
which points at C2 symmetry of compound 7.
Thus, we developed the efficient method of the cataꢀ
lytic cycloaddition of diazoacetates containing substituꢀ
ents of diverse structure in the ester group to the fullerene
C60. This reveals sufficiently simple and effective way to
the synthesis of new practically important carboxy derivaꢀ
tives of the methanofullerenes with the substituents of diꢀ
verse nature, including those based on steroids.
Experimental
In the experiments, a commercially accessible [60]fullerene
with 99.5% purity (G. A. Razuvaev Institute of Metalloorganic
Chemistry of Russian Academy of Sciences, Nizhnii Novgorod).
The reaction products were analyzed by HPLC on a chromatoꢀ
graph Altex 330 (USA) with UV detector at 340 nm. The mixture
components were separated on a metallic column Cosmosil
Buckyprep Waters, 250×10 mm, at ~20 °C. A mobile phase is
toluene, flow rate 2.0 mL min–1. IR spectra were recorded on
a Specord 75 IR spectrophotometer and IR Fourier spectromeꢀ
ter Bruker VERTEX 70V in KBr tablets or in CHCl3. UV spectra
were recorded on spectrophotometers Specord Mꢀ40 and Perꢀ
kin—Elmer Lambda 750. 1H and 13C NMR spectra were recorded
on a spectrometer Bruker Avanceꢀ400 (400.13 and 100.62 MHz,
respectively). The solvent was a mixture CDCl3—CS2 (1 : 5).
1´aꢀCyclohexyloxycarbonylꢀ1´aꢀcarbaꢀ1´(2´)aꢀhomo(C60ꢀIh)ꢀ
[5,6]fullerene (stereoisomer 5b). 1H NMR (δ): 1.20—2.20 (m, 10 H,
5 CH2); 4.76—4.83 (m, 1 H, CH); 7.40 (s, 1 H, CH). 13C NMR

Cycloaddition of diazoacetates to [60]fullerene
Russ.Chem.Bull., Int.Ed., Vol. 59, No. 10, October, 2010
1963
(δ): 24.46, 25.93, 31.81, 52.15, 74.55, 131.33, 137.19, 138.74,
138.82, 140.99, 142.02, 142.31, 142.36, 142.63, 143.55, 143.92,
144.37, 144.45, 144.72, 144.93, 145.03, 145.63, 147.68, 164.38.
1´aꢀCyclohexyloxycarbonylꢀ1´aꢀcarbaꢀ1´(2´)aꢀhomo(C60ꢀIh)ꢀ
[5,6]fullerene (stereoisomer 6b). 1H NMR (δ): 1.20—2.20 (m, 10 H,
5 CH2); 3.76 (s, 1 H, CH); 5.16—5.26 (m, 1 H, CH). 13C NMR
(δ): 24.30, 25.93, 31.99, 54.54, 75.30, 133.50, 134.04, 135.17,
137.87, 138.07, 138.30, 138.53, 138.53, 140.24, 141.81, 142.02,
142.19, 142.44, 142.63, 142.88, 143.03, 143.09, 143.30, 143.40,
143.70, 143.79, 144.03, 144.68, 144.72, 144.93, 145.21, 145.27,
147.87, 168.45.
0.91 (d, 3 H, Me, J = 6.8 Hz); 0.99—2.05 (m, 27 H, 6 CH,
9 CH2, Me); 1.14 (s, 3 H, Me); 2.06—2.11 (m, 2 H, CH2); 2.60
(d, 2 H, CH2, J = 8.0 Hz); 4.74 (s, 1 H, CH); 4.96 (m, 1 H, CH);
5.49 (m, 1 H, CH). 13C NMR (δ): 12.17, 19.03, 19.60, 21.43,
22.87, 23.12, 24.24, 24.77, 28.42, 28.73, 30.16, 32.06, 32.39,
36.10, 36.55, 36.81, 37.36, 38.48, 39.65, 39.83, 40.11, 42.49,
50.25, 56.42, 56.95, 70.87 (sp3), 76.40, 123.66, 139.09, 140.70,
140.95, 141.24, 142.07, 142.50, 142.81, 143.03, 143.37, 143.78,
144.02, 144.65, 144.68, 145.13, 145.22, 145.29, 145.83, 148.58,
164.79. MS (MALDIꢀTOF), m/z: found: 1147.542; for С89Н46О2
calculated: 1147.316.
1´ꢀAllyloxycarbonylꢀ(C60ꢀIh)[5,6]fullereno[2´,3´:1,9]cycloꢀ
propane (4c). IR, ν/cm–1: 530, 760, 1090, 1150, 1180, 1420,
1640, 1740. UV (CHCl3), λmax/nm: 260, 330, 427. 1H NMR (δ):
4.80 (s, 1 H, CH); 4.96 (d, 2 H, CH2, J = 5.6 Hz); 5.44 (d, 2 H,
CH2, J = 10.4 Hz); 6.08—6.17 (m, 1 H, CH). 13C NMR (δ):
39.80, 66.89, 70.63 (sp3), 119.65, 131.61, 140.65, 141.10, 141.21,
142.09, 142.25, 142.36, 142.43, 142.97, 143.04, 143.12, 143.27,
143.41, 143.78, 144.23, 144.36, 144.66, 144.70, 145.00, 145.12,
145.23, 145.38, 145.61, 145.84, 148.39, 165.03.
This work was financially supported by Presidium of
the Russian Academy of Sciences (Program "Fundamental
Sciences for Medicine") and Ministry of Education and
Science of the Russian Federation (Federal Target Proꢀ
gram "Human Resources for Science, Research, Educaꢀ
tion and Innovation in Russia for 2009—2013", State conꢀ
tract No. P1218).
1´aꢀAllyloxycarbonylꢀ1´aꢀcarbaꢀ1´(2´)aꢀhomo(C60ꢀIh)[5,6]ꢀ
fullerene (stereoisomer 5c). 1H NMR (δ): 7.36 (s, 1 H, CH); 4.71
(d, 2 H, CH2, J = 5.6 Hz); 5.38 (d, 2 H, CH2, J = 10.8 Hz);
5.93—6.04 (m, 1 H, CH). 13C NMR (δ): 51.92, 66.63, 119.14,
131.43, 134.11, 136.57, 138.76, 138.83, 140.82, 142.01, 142.33,
142.37, 142.87, 143.57, 143.87, 144.33, 144.48, 144.70, 144.89,
145.10, 145.68, 147.74, 165.18.
1´aꢀAllyloxycarbonylꢀ1´aꢀcarbaꢀ1´(2´)aꢀhomo(C60ꢀIh)[5,6]ꢀ
fullerene (stereoisomer 6c). 1H NMR (δ): 3.81 (s, 1 H, CH); 5.00
(d, 2 H, CH2, J = 5.6 Hz); 5.53 (d, 2 H, CH2, J = 10.4 Hz);
6.12—6.23 (m, 1 H, CH). 13C NMR (δ): 54.16, 67.10, 119.49,
131.53, 137.85, 138.03, 138.34, 138.56, 138.52, 140.27, 141.90,
142.00, 142.21, 142.45, 142.66, 142.84, 143.05, 143.12, 143.31,
143.38, 143.42, 143.69, 143.78, 144.16, 144.68, 144.81, 144.96,
145.21, 145.28, 168.76.
1´ꢀBenzyloxycarbonylꢀ(C60ꢀIh)[5,6]fullereno[2´,3´:1,9]ꢀ
cyclopropane (4d). IR, ν/cm–1: 545, 860, 1155, 1190, 1270. UV
(CHCl3), λmax/nm: 260, 327, 427. 1H NMR (δ): 4.81 (s, 1 H,
CH); 5.53 (s, 2 H, CH2); 7.22 (t, 1 H, CH, J = 7.2 Hz); 7.43
(t, 2 H, 2 CH, J = 7.2 Hz); 7.56 (d, 2 H, 2 CH, J = 7.2 Hz).
13C NMR (δ): 39.06, 68.33, 70.72 (sp3), 127.67 (Ph), 129.03
(Рh), 130.56 (Рh), 136.46 (Рh), 136.64, 140.67, 140.99, 141.23,
142.00, 142.18, 142.32, 142.50, 142.87, 143.04, 143.11, 143.13,
143.40, 143.78, 144.02, 144.47, 144.68, 144.72, 144.92, 145.13,
145.23, 145.28, 145.63, 145.83, 148.36, 165.43. MS (MALDIꢀTOF),
m/z: found: 868.813; for С69Н8О2 calculated: 868.801.
1´aꢀBenzyloxycarbonylꢀ1´aꢀcarbaꢀ1´(2´)aꢀhomo(C60ꢀIh)ꢀ
[5,6]fullerene (6d). 1H NMR (δ): 3.82 (s, 1 H, CH); 5.48 (s, 2 H,
CH2); 7.27 (t, 1 H, CH, J = 7.2 Hz); 7.40 (t, 2 H, 2 CH, J = 7.2 Hz);
7.45 (d, 2 H, 2 CH, J = 7.2 Hz). 13C NMR (δ): 54.21, 68.16,
128.82 (Рh), 128.91 (Рh), 130.56 (Рh), 134.96 (Рh), 135.49,
136.55, 137.07, 138.04,138.27, 138.97, 139.29, 140.46, 141.54,
142.24, 142.30, 142.50, 142.97, 143.21, 143.25, 143.49, 143.51,
143.62, 143.70, 144.20, 144.60, 144.73, 145.14, 147.59, 169.09.
1´ꢀCholesteryloxycarbonylꢀ(С60ꢀIh)[5,6]fullereno[2´,3´:1,9]ꢀ
cyclopropane (7). IR, ν/cm–1: 527, 756, 1186, 1436, 1464, 1629,
1737, 2865, 2931. UV (CHCl3), λmax/nm: 259, 327, 426.
1H NMR (δ): 0.74 (s, 3 H, Me); 0.90 (d, 3 Н, Me, J = 6.8 Hz);
References
1. C. Toniolo, A. Bianco, M. Maggini, G. Scorrano, M. Prato,
M. Marastoni, R. Tomatis, S. Spisani, G. Palu, E. D. Blair,
J. Med. Chem., 1994, 37, 4558.
2. C. C. Zhu, Y. Xu, Y. Q. Liu, D. B. Zhu, J. Org. Chem., 1997,
62, 1996.
3. J. C. Hummelen, B. W. Knight, F. LePeq, F. Wudl, J. Yao,
C. L. Wilkins, J. Org. Chem., 1995, 60, 532.
4. R. Gonzalez, J. C. Hummelen, F. Wudl, J. Org. Chem., 1995,
60, 2618.
5. L. B. Piotrovsky, O. I. Kiselev, Fullereny v Biologii [Fullerenes
in Biology], Rostok, St. Petersburg, 2006, p. 336 (in Russian).
6. T. Tada, Y. Ishida, K. Saigo, J. Org. Chem., 2006, 71, 1633.
7. H. Ito, T. Tada, M. Sudo, Y. Ishida, T. Hino, K. Saigo, Org.
Lett., 2003, 5, 2643.
8. I. G. Safonov, P. S. Baran, D. I. Schuster, Tetrahedron Lett.,
1997, 38, 8133.
9. G. Fernandez, E. M. Perez, L. Sanchez, N. Martin, J. Am.
Chem. Soc., 2008, 130, 2410.
10. A. R. Tuktarov, A. R. Akhmetov, R. F. Kamalov, L. M.
Khalilov, M. Pudas, A. G. Ibragimov, U. M. Dzhemilev, Zh.
Org. Khim., 2009, 45, 1180 [Russ. J. Org. Chem. (Engl. Transl.),
2009, 45].
11. A. R. Tuktarov, A. R. Akhmetov, D. Sh. Sabirov, L. M.
Khalilov, A. G. Ibragimov, U. M. Dzhemilev, Izv. Akad.
Nauk, Ser. Khim., 2009, 1671 [Russ. Chem. Bull., Int. Ed.,
2009, 58, 1724].
12. G. Fernandez, E. M. Perez, L. Sanchez, N. Martin, J. Am.
Chem. Soc., 2008, 130, 2410.
13. L. Isaacs, A. Wehrsig, F. Diederich, Helv. Chim. Acta, 1993,
76, 1231.
Received June 8, 2010;
in revised form August 12, 2010