Synthesis of Fullerotetrahydroquinolines via [4 + 2] Cycloaddition Reaction of [60]Fullerene with in Situ Generated Aza-o-quinone Methides

Article abstract of DOI:10.1021/acs.joc.7b02897

An efficient [4 + 2] cycloaddition reaction of [60]fullerene with the in situ generated aza-o-quinone methides from N-(o-chloromethyl)aryl sulfonamides with the assistance of Cu₂O has been developed to afford a series of fullerotetrahydroquinol

Full text of DOI:10.1021/acs.joc.7b02897

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Article
Synthesis of Fullerotetrahydroquinolines via [4+2] Cycloaddition
Reaction of [60]Fullerene with in Situ Generated Aza-o-quinone Methides
Sheng-Peng Jiang, Wen-Qiang Lu, Zhan Liu, and Guan-Wu Wang
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.7b02897 • Publication Date (Web): 23 Jan 2018
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Synthesis of Fullerotetrahydroquinolines via [4+2]
Cycloaddition Reaction of [60]Fullerene with in Situ Generated
Azaꢀoꢀquinone Methides
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ShengꢀPeng Jiang,† WenꢀQiang Lu,† Zhan Liu,† and GuanꢀWu Wang*,†,‡
†CAS Key Laboratory of Soft Matter Chemistry, iChEM (Collaborative Innovation
Center of Chemistry for Energy Materials), Hefei National Laboratory for Physical
Sciences at Microscale, and Department of Chemistry, University of Science and
Technology of China, Hefei, Anhui 230026, P. R. China
‡State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou,
Gansu 730000, P. R. China
ABSTRACT
An efficient [4+2] cycloaddition reaction of [60]fullerene with the in situ generated
azaꢀoꢀquinone methides from Nꢀ(orthoꢀchloromethyl)aryl sulfonamides with the
assistance of Cu2O has been developed to afford
a
series of
fullerotetrahydroquinolines. This strategy exhibits a broad substrate scope and
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excellent functional group tolerance. A tentative reaction pathway for the formation of
fullerotetrahydroquinolines is proposed on the basis of the experimental results.
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INTRODUCTION
As a consequence of the huge potential applications in materials, biology, and
nanoscience, fullerene derivatives have continued to capture the interest of chemists
worldwide.1 As a result, numerous efforts have been devoted to the efficient
construction of various organofullerenes during the past two decades. Among them,
[4+2] cycloaddition is one of the most commonly used methods to synthesize
[60]fullerene (C60)ꢀfused sixꢀmembered carbocyclic derivatives.2 However, reports on
the formation of C60ꢀfused sixꢀmembered heterocyclic derivatives via [4+2]
cycloaddition are relatively limited.3 In the early 1990s, Eguchi and coꢀworkers
reported heteroꢀDielsꢀAlder reactions of C60 yielding C60ꢀfused dihydropyran and
dihydrothiopyran derivatives through the C–O and C–S bond formation,
respectively.3a–c In 1998, the Martin group realized the first synthesis of
nitrogenꢀbonded C60 derivatives via heteroꢀDielsꢀAlder reaction of C60 with
oꢀaminobenzyl alcohols, which were prepared by the reaction of aldehydes with
Nꢀmethylanilinochlorophenylborane in refluxing oꢀdichlorobenzene for 5 h.3e Since
then, there has been no report on the heteroꢀDielsꢀAlder reaction of C60. Therefore,
the development of a more straightforward, reliable, and practical method for the
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synthesis of diverse C60ꢀfused sixꢀmembered heterocyclic derivatives through [4+2]
cycloaddition is desirable and challenging.
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On the other hand, orthoꢀquinone methides (oQMs) are versatile intermediates
and have been found extensive applications in organic chemistry due to their highly
polarized and quite reactive properties.4 The cycloaddition reaction of oQMs with
various dienophiles provides a facile and efficient method for the construction of
heterocyclic compounds. Compared to the wellꢀdeveloped oQMs, the related reports
on analogous azaꢀoꢀquinone methides (aoQMs) as reactive intermediates in the
cycloaddition are much less investigated. To date, several methods have been
developed for the formation of aoQMs by photolysis,5 pyrolysis,6 fluorideꢀinduced
elimination,7 and baseꢀpromoted elimination.8 To the best of our knowledge, the in
situ formation of aoQMs assisted by a metal oxide has never been reported.
Additionally, it is well recognized that C60 behaves as an electronꢀdeficient olefin and
undergoes various types of cycloaddition reactions.2,3 We envisioned that C60 should
react with the in situ generated aoQMs to form nitrogenꢀbearing sixꢀmembered
organofullerenes. In view of our continuing interest in fullerene chemistry,9,10 herein
we report the synthesis of fullerotetrahydroquinolines through heteroꢀDielsꢀAlder
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reaction of C60 with the in situ generated aoQMs from
sulfonamides with the assistance of Cu2O.
Nꢀ(orthoꢀchloromethyl)aryl
RESULTS AND DISCUSSION
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We initiated our study with the model reaction of C60 (0.05 mmol) and
Nꢀ(2ꢀ(chloromethyl)phenyl)ꢀ4ꢀmethylbenzenesulfonamide 1a (2.0 equiv) in
anhydrous chlorobenzene (CB) at 120 °C under an openꢀair atmosphere (Table 1). The
anticipated product 2a could be isolated in 3% yield without any additive (entry 1). It
was reported that aoQMs could be efficiently generated in situ under basic
conditions.8 Therefore, we conducted the reaction in the presence of Na2CO3 (2.0
equiv), and the yield of 2a was increased to 13% (entry 2). The yield could be further
improved to 21% when K2CO3 was used (entry 3). To our disappointment, Cs2CO3,
which was frequently employed as the base for the in situ generation of aoQMs from
Nꢀ(orthoꢀchloromethyl)aryl amides,8aꢀc,eꢀh could hardly promote the formation of 2a
(entry 4). In continuing our interest in copperꢀinvolved functionalizations of C60,10
when Cu2O (2.0 equiv) was utilized to replace K2CO3, a better yield of 33% was
obtained (entry 5 vs entry 3). To further improve the practicability of the reaction, a
catalytic amount (0.2 equiv) of Cu2O was used. Unfortunately, the yield of 2a dropped
dramatically to 19% (entry 6). To our delight, the yield was increased to 25% when
0.2 equiv of 1,10ꢀphenanthroline (1,10ꢀphen) was added as a ligand to the reaction
(entry 7), and the yield was further improved to 33% when 0.3 equiv of 1,10ꢀphen
was employed (entry 8). Nevertheless, increasing the amount of 1,10ꢀphen to 0.4
equiv led to a slight decrease of the product yield to 26% (entry 9). It was not
beneficial to the formation of 2a when the amount of Cu2O was decreased from 0.2
equiv to 0.1 equiv, giving 2a in only 17% yield (entry 10). Increasing the loading of
Cu2O to 0.3 equiv did not afford a better result (entry 11 vs entry 8). Next,
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2,2ꢀbipyridyl (bpy) was employed as the ligand, the yield was decreased slightly to
28%, whereas the yield dropped obviously by replacing with triphenylphosphine
(PPh3), providing 2a in only 15% yield (entries 12 and 13 vs entry 8). Different
copper salts were subsequently evaluated and attempted to further enhance the
product yield. To our disappointment, Cu(I) salts such as CuCN, CuSCN, CuCl, CuBr,
and CuI could not facilitate the reaction (entries 14–18 vs entry 1). Similar poor
results were obtained when CuO, Cu(OTf)2, Cu(OAc)2·H2O, and CuCl2 were
employed (entries 19–22). The decrease or increase of the loading of substrate 1a was
not beneficial to the improvement of the yield, giving 2a in 27% and 28% yields,
respectively (entries 23 and 24). Reducing or elevating the temperature both
decreased the reaction efficiency, providing 2a in 24% and 27% yields, respectively
(entries 25 and 26). In addition, the variation of the reaction time was also
investigated, and the results demonstrated that the reaction time of 3.0 h was the best
(entries 27 and 28 vs entry 8). Carrying out the reaction under a dry air atmosphere
led to a slightly reduced yield of 28% (Table 1, entry 29 vs entry 8). Similarly, the
desired product 2a was isolated in 28% yield under an oxygen atmosphere (Table 1,
entry 30 vs entry 8). It is noteworthy that a decreased yield of 25% was obtained
under a nitrogen atmosphere, indicating that the openꢀair atmosphere had certain
beneficial influence on the reaction efficiency (Table 1, entry 31 vs entry 8). Thus, the
optimal reaction conditions were a molar ratio of 1/2/0.2/0.3 for the reagents C60, 1a,
Cu2O, and 1,10ꢀphen, and a temperature of 120 °C for 3 h in anhydrous
chlorobenzene (6 mL) under an openꢀair atmosphere.
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Table 1. Optimization of Reaction Conditionsa
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entry
1
copper/additive
/
molar ratiob
1:2:0:0
yield (%)c
3 (75)
2
Na2CO3
1:2:0:2
13 (57)
21 (75)
3 (43)
3
K2CO3
1:2:0:2
4
Cs2CO3
1:2:0:2
5
Cu2O
1:2:2:0
33 (77)
19 (70)
25 (74)
33 (83)
26 (74)
17 (68)
33 (73)
28 (72)
15 (71)
6 (67)
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Cu2O
1:2:0.2:0
1:2:0.2:0.2
1:2:0.2:0.3
1:2:0.2:0.4
1:2:0.1:0.15
1:2:0.3:0.45
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
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Cu2O/1,10ꢀphen
Cu2O/1,10-phen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/bpy
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Cu2O/PPh3
CuCN/1,10ꢀphen
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CuSCN/1,10ꢀphen
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:1.5:0.2:0.3
1:2.5:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
1:2:0.2:0.3
4 (67)
3 (33)
CuCl/1,10ꢀphen
CuBr/1,10ꢀphen
CuI/1,10ꢀphen
17
4 (67)
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3 (50)
19
CuO/1,10ꢀphen
14 (74)
3 (75)
20
Cu(OTf)2/1,10ꢀphen
Cu(OAc)2·H2O/1,10ꢀphen
CuCl2/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
Cu2O/1,10ꢀphen
21
3 (75)
22
3 (99)
23
27 (75)
28 (61)
24 (83)
27 (64)
25 (68)
27 (84)
28 (88)
28 (85)
25 (71)
24
25d
26e
27f
28g
29h
30i
31j
aUnless otherwise noted, the reactions were performed in anhydrous chlorobenzene (6
b
mL) at 120°C under an openꢀair atmosphere for 3.0 h. Molar ratio referred to
c
C60/1a/copper/additive. Isolated yields. Values in parentheses were based on the
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d
e
consumed C60. The reaction was performed at 110 °C. The reaction was performed
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f
g
h
at 130 °C. The reaction time was 4.0 h. The reaction time was 2.0 h. The reaction
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was performed under a dry air atmosphere. The reaction was performed under an
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oxygen atmosphere. jThe reaction was performed under a nitrogen atmosphere.
The substrate scope of this transformation was then investigated under the
optimized reaction conditions, and the results are presented in Table 2. At first, the
reaction of C60 with Nꢀ(2ꢀ(chloromethyl)aryl)ꢀ4ꢀmethylbenzenesulfonamides 1
bearing different substituents on the aromatic ring was examined. The reaction
showed good tolerance for diverse electronꢀdonating or electronꢀwithdrawing groups
at different positions on the aromatic ring of substrates 1, giving the corresponding
products 2b–f in 23–36% yields. The substrates with electronꢀdonating substituents
(1c–e) generally exhibited higher reactivity than that with an electronꢀwithdrawing
group (1f), probably because the electronꢀdonating substituents would make the
aoQMs more electronꢀrich and thus facilitated the subsequent cycloaddition with
electronꢀdeficient C60. In addition, the influence of the substituents at different
positions of the aromatic ring was not obvious except for the substituent at the
orthoꢀposition of the sulfonamide moiety due to steric effect. For example, a higher
reaction temperature of 140 °C was essential for 1b to achieve the synthetically
valuable product yield. It is worth noting that the disubstituted
Nꢀ(2ꢀ(chloromethyl)aryl)ꢀ4ꢀmethylbenzenesulfonamide 1e with two strong
electronꢀdonating methoxy groups efficiently afforded cycloadduct 2e in 36% yield.
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The chloro atom on the phenyl ring could be tolerated under the optimal reaction
conditions, and can be utilized for further functionalizations at a later stage using
crossꢀcoupling protocols. Moreover, substrate 1g with a phenyl substituent at the
benzylic position also proceeded well to produce the corresponding product 2g, albeit
in a relatively lower yield.
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Table 2. Results for the [4+2] Cycloaddition Reaction of C60 with 1a–ga,b
aUnless otherwise noted, the reactions were performed with C60 (0.05 mmol), 1 (0.10
mmol), Cu2O (0.01 mmol), and 1,10ꢀphen (0.015 mmol) in anhydrous chlorobenzene
(6 mL) at 120 °C under an openꢀair atmosphere. bIsolated yields. Values in
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parentheses were based on the consumed C60. cThe reaction was performed at 140 °C.
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dMolar ratio of C60/1/Cu2O/1,10ꢀphen is 1/2/0.5/0.75.
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To further expand the scope of this transformation, Nꢀ(2ꢀ(chloromethyl)phenyl)
sulfonamides 1 with a wide range of different sulfonamide moieties were then
examined, and the results are shown in Table 3. The substrates 1h–p with both
electronꢀrich and electronꢀdeficient sulfonamide groups underwent effective
transformations, giving the corresponding products 2h–p in 26–34% yields. The oꢀ
and mꢀmethyl substituted substrates (1i and 1j) proceeded well with good yields of
32% and 31%, respectively, which were nearly the same as that (33%) of product 2a,
suggesting that the steric effect of the substituents on the aromatic ring of the
sulfonamide moiety was negligible. Nevertheless, the electronic nature of the
substituents on the phenyl ring of the sulfonamide moiety had an obvious influence on
the reaction. For example, substrates 1k and 1m bearing either a strong
electronꢀdonating or electronꢀwithdrawing group at the 4ꢀposition decreased the
reaction conversion and required a higher reaction temperature of 140 °C to produce
2k and 2m in 26% and 28% yields, respectively. Electronꢀrich heterocycleꢀcontaining
sulfonamide 1n was also a suitable substrate for this transformation, affording 2n in
33% yield. When the arylsulfonamide group of the substrates was changed to an
alkylsulfonamide moiety as in the cases of 1o and 1p, the transformations also
proceeded well, providing the corresponding products 2o and 2p in 29% and 31%
yields, respectively.
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Table 3. Results for the [4+2] Cycloaddition Reaction of C60 with 1h–pa,b
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Cu2O (20 mol %)
1,10-phen (30 mol %)
120 oC, CB (6 mL)
Cl
+
NHSO2R3
N
O2S
R3
1
2
N
N
O2S
N
O2S
O2S
2h, 3 h, 34% (72%)
2i, 3 h, 32% (80%)
2j, 3 h, 31% (79%)
N
N
O2S
N
O2S
O2S
OMe
Cl
NO2
2k, 5 h, 26% (76%)c
2m, 5 h, 28% (74%)c
2l, 3 h, 30% (91%)
N
N
O2S
N
O2S
O2S
S
2n, 3 h, 33% (89%)c
2o, 3 h, 29% (85%)
2p, 3 h, 31% (78%)
aUnless otherwise noted, the reactions were performed with C60 (0.05 mmol), 1 (0.10
mmol), Cu2O (0.01 mmol), and 1,10ꢀphen (0.015 mmol) in anhydrous chlorobenzene
(6 mL) at 120 °C under an openꢀair atmosphere. bIsolated yields. Values in
parentheses were based on the consumed C60. cThe reaction was performed at 140 °C.
The structures of products 2a–p were unambiguously characterized by using
HRMS (MALDIꢀTOF), 1H NMR, 13C NMR, FTꢀIR, and UVꢀvis spectra. All HRMS of
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these products exhibited the correct [M]+ peaks. Their 1H NMR spectra displayed the
expected chemical shifts as well as the splitting patterns for all protons. The 13C NMR
spectra of 2a–p exhibited more than 49 peaks in the range of 157–133 ppm for the 58
sp2ꢀcarbons of the fullerene cage and two peaks at 82–67 ppm for the two sp3ꢀcarbons
of the fullerene skeleton, consistent with the C1 symmetry of their molecular
structures. To further confirm the structure, the HSQC and HMBC spectra were
carried out using 2c as a representative example. The HSQC spectrum of 2c
displayed that the protons at 4.80 ppm and 4.05 ppm had correlations with the
carbon at 42.2 ppm. The HMBC spectrum of 2c showed that the protons at 4.80
ppm and 4.05 ppm were correlated with the two sp3ꢀcarbons of C60 at 80.3 ppm
and 67.9 ppm. These 2DꢀNMR results were fully consistent with that 2c had a
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structure of fullerotetrahydroquinoline. The UVꢀvis spectra of 2a–p exhibited a peak
at 433–434 nm, which is the characteristic absorption for 1,2ꢀadducts of C60.
To gain insight for the reaction mechanism of this transformation, some control
experiments were conducted (Scheme 1). Addition of the wellꢀknown radical
scavenger 2,2,6,6ꢀtetramethylpiperidineꢀ1ꢀoxyl (TEMPO, 2.0 equiv) to the reaction
mixture had nearly negligible effect on the transformation, giving 2a in 30% yield.
Additionally, when 2,6ꢀditertbutylꢀ4ꢀmethyiphenol (BHT, 2.0 equiv) was used as the
radical scavenger, the formation of 2a could not be prohibited significantly either, and
2a was isolated in 22% yield. The above observations indicated that radical species
may be not involved in this transformation. Previous work has shown that C60 is an
excellent electrophile and reacts with a variety of nucleophilic reagents. The acidic N–
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H proton could be deprotonated under basic conditions to give the sulfonamide anion,
which may undergo nucleophilic attack to C60 to afford the
fullerotetrahydroquinolines. To test this hypothesis, we did the following control
experiments. The reaction of C60 with 1a in the presence of benzyl chloride (2 equiv)
was performed under the standard conditions, and nearly the same yield (32%) of 2a
as that (33%) in the absence of benzyl chloride was obtained. The possible benzylated
product 2a-CH2Ph, which would be formed by the initial nucleophilic attack of the
sulfonamide anion to C60 followed by intramolecular SN2 reaction to benzyl chloride,
could not be identified. Furthermore, the reaction of C60 with Nꢀphenyl
paraꢀtoluenesulfonylamine in the presence/absence of benzyl chloride were
conducted under otherwise the same conditions, and no fullerene product could be
isolated. On the other hand, treatment of 1a with 2,3ꢀdihydrofuran under the optimal
reaction conditions could deliver the [4+2] cycloaddition product 3a in 46% yield
(Scheme 1). Considering the electroꢀrich nature of 2,3ꢀdihydrofuran, the possibility
through nucleophilic addition of 1a to 2,3ꢀdihydrofuran to give 3a was negligible. The
above results suggested that a stepwise reaction mechanism involving the initial
nucleophilic attack of the sulfonamide anion to C60 could be excluded, and thus the
formation of 2 should proceed most likely via a heteroꢀDielsꢀAlder process.
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Scheme 1. Control Experiments
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Furthermore, after the reaction was completed, we observed a green copper
precipitate, which was the same as that formed from the control reaction of 1a with
Cu2O and 1,10ꢀphen at 120 °C for 3 h in CB. The electron paramagnetic resonance
(EPR) experiment of the green solid in DMSO suggested that a Cu(II) species
existed.11 The XꢀRay diffraction experiment further confirmed that the single crystal 4
grown from the green copper solid was a complex of 1,10ꢀphen and CuCl2 (see the
Supporting Information).12 To gain deep insight into the mechanism, Xꢀray
photoelectron spectroscopy (XPS) was used to investigate the oxidation state of the
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copper solid obtained from the reaction mixture. The binding energy (BE) peak at
∼934 eV was assigned to a Cu2+ species.13 The BE peak at ∼931.5 eV suggested the
presence of a Cu+ or Cu0 species.13 Because Cu 2p3/2 XPS could not differentiate Cu+
from Cu0, Auger Cu LMM spectrum was used to confirm the presence of Cu+ at BE ∼
571 eV, and no Cu0 species was present in our system because there was no BE peak
at ∼568 eV in the Auger Cu LMM spectrum (see the Supporting Information).14 Thus,
the copper solid obtained from the reaction mixture should consist of Cu(phen)Cl2 and
Cu2O. The XPS experiment was also employed to study the oxidation state of the
copper species for the reaction under a nitrogen atmosphere. The results indicated that
no Cu0 species was generated and Cu2O, CuCl, and Cu(phen)Cl2 were observed (see
the Supporting Information).
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The possible pathway for the formation of aoQM and 4 is shown in Scheme 2.
The removal of HCl from substrate 1a generates the aoQM intermediate, likely with
the assistance of Cu2O. The reaction of Cu2O and HCl provides CuCl, which is
converted to CuCl2 in the presence of HCl and O2. Then 4 is produced when CuCl2 is
coordinated with 1,10ꢀphen (Scheme 2).
Scheme 2. Formation of aoQM and Complex 4
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On the basis of the above experimental results and literature precedents,8 a
plausible reaction mechanism of this transformation is presented in Scheme 3. First,
the aoQM intermediate A could be generated in situ from Nꢀ(orthoꢀchloromethyl)aryl
sulfonamide 1 with the assistance of Cu2O and 1,10ꢀphen, accompanied by the
simultaneous release of complex 4 and H2O. Although the exact role played by Cu2O
is not very clear, it may behave as a base for the removal of HCl from 1, and also
consumes the generated HCl to generate CuCl and eventually complex 4 in the
presence of O2 and 1,10ꢀphen. Intermediate A then undergoes the heteroꢀDielsꢀAlder
reaction with C60 to provide the desired product 2.
Scheme 3. Proposed Reaction Mechanism for the Formation of 2
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CONCLUSION
In summary, we have successfully developed an efficient and convenient method for
the synthesis of fullerotetrahydroquinolines from the heteroꢀDielsꢀAlder reaction of
C60
with
the
in
situ
generated
azaꢀoꢀquinone
methides
from
Nꢀ(orthoꢀchloromethyl)aryl sulfonamides with the assistance of catalytic amounts of
Cu2O and 1,10ꢀphenanthroline, which are more efficient than the commonly used
inorganic bases such as Cs2CO3, Na2CO3, and K2CO3. This is the first example of the
metal oxideꢀinduced in situ formation of azaꢀoꢀquinone methides. The present method
features a broad substrate scope and good functional group tolerance.
EXPERIMENTAL SECTION
1
General Methods. H NMR spectra were referenced to residual DMSO at 2.50 ppm
or TMS at 0.00 ppm, while 13C NMR spectra were referenced to residual DMSO at
39.50 ppm, CHCl2CHCl2 at 72.80 ppm, or CHCl3 at 77.16 ppm. Highꢀresolution mass
spectra (HRMS) were obtained by MALDIꢀTOF in a positive mode or ESIꢀFTꢀICR in
a positive mode.
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General Procedure for the Synthesis of 2a–p from the Reaction of C60 with
1a–p. A mixture of C60 (0.05 mmol), Nꢀ(2ꢀ(chloromethyl)aryl)ꢀsulfonamide 1 (0.10
mmol), Cu2O (0.01 mmol), and 1,10ꢀphenanthroline (1,10ꢀphen) (0.015 mmol) was
dissolved in anhydrous chlorobenzene (6 mL). Then the solution was vigorously
stirred at the desired temperature and stopped at the designated time. The resulting
solution was evaporated in vacuo, and the residue was then separated on a silica gel
column. The recovered C60 was firstly collected with CS2 as the eluent. Then the
eluent was changed to CS2/CH2Cl2 (15:1 v/v unless specified) to separate out the
desired product 2.
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60
Fullerotetrahydroquinoline 2a. By following the general procedure, the reaction of
C60
(35.9
mg,
0.05
mmol)
with
Nꢀ(2ꢀ(chloromethyl)phenyl)ꢀ4ꢀmethylbenzenesulfonamide 1a (29.7 mg, 0.10 mmol),
o
Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (3.0 mg, 0.015 mmol) at 120 C for 3.0 h
afforded recovered C60 (21.5 mg, 60%) and 2a (16.0 mg, 33%): amorphous brown
solid; 1H NMR (400 MHz, CS2 with DMSOꢀd6 as the external reference) δ 7.64 (d, J
= 8.2 Hz, 2H), 7.58 (d, J = 7.6 Hz, 1H), 7.41–7.30 (m, 3H), 7.04 (d, J = 8.2 Hz, 2H),
4.35 (d, J = 13.6 Hz, 1H), 3.75 (d, J = 13.6 Hz, 1H), 2.23 (s, 3H); 13C NMR (100
MHz, CS2 with DMSOꢀd6 as the external reference) δ 156.0, 153.9, 151.8, 147.5,
146.9, 146.7, 145.94, 145.91, 145.8, 145.7, 145.53, 145.48, 145.46, 145.3, 145.04,
145.03, 145.0, 144.9, 144.69, 144.68, 144.65, 144.61, 144.58, 144.4, 144.1, 143.87,
143.85, 143.84, 143.1, 143.0, 142.8, 142.4, 142.1, 142.0, 141.94, 141.88, 141.8, 141.7,
141.6, 141.5, 141.3, 141.02, 140.98, 140.94, 140.8, 140.5, 140.3, 139.8, 139.2, 138.94,
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138.89, 138.3, 137.4, 137.3, 136.6, 135.8, 135.4, 134.4, 129.8, 128.9, 128.2, 128.0,
5
6
7
127.74, 127.69, 80.7 (sp3ꢀC of C60), 68.4 (sp3ꢀC of C60), 43.0, 21.2; FTꢀIR ν/cmꢀ1 (KBr)
8
9
1333 (S=O), 1159 (S=O), 814 (N–S); UVꢀvis (CHCl3) λmax/nm (log ε) 258 (5.05), 317
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60
(4.60), 434 (3.43), 697 (2.65); HRMS (MALDIꢀTOF) m/z calcd for C74H13NO2S [M]+
979.0662, found 979.0653.
Fullerotetrahydroquinoline 2b. By following the general procedure, the reaction of
C60
(35.8
mg,
0.05
mmol)
with
Nꢀ(2ꢀ(chloromethyl)ꢀ6ꢀmethylphenyl)ꢀ4ꢀmethylbenzenesulfonamide 1b (30.7 mg,
0.10 mmol), Cu2O (3.7 mg, 0.025 mmol), and 1,10ꢀphen (7.3 mg, 0.0375 mmol) at
o
140 C for 6.0 h afforded recovered C60 (26.1 mg, 73%) and 2b (11.4 mg, 23%):
1
amorphous brown solid; H NMR (400 MHz, CS2 with DMSOꢀd6 as the external
reference) δ 7.98 (d, J = 8.2 Hz, 2H), 7.49–7.41 (m, 3H), 7.24 (d, J = 8.2 Hz, 2H),
5.14 (d, J = 13.7 Hz, 1H), 3.99 (d, J = 13.7 Hz, 1H), 2.71 (s, 3H), 2.44 (s, 3H); 13C
NMR (100 MHz, CS2 with DMSOꢀd6 as the external reference) δ 156.4, 154.3, 151.6,
147.5, 146.9, 146.5, 146.00, 145.96, 145.8, 145.7, 145.55, 145.53, 145.48, 145.4,
145.2, 145.02, 144.96, 144.9, 144.74, 144.71, 144.66, 144.5, 144.2, 144.0, 143.84,
143.81, 143.3, 143.0, 142.9, 142.5, 142.15, 142.06, 142.05, 142.02, 141.9, 141.8,
141.63, 141.62, 141.60, 141.4, 141.1, 141.02, 140.96, 140.9, 140.5, 140.1, 139.9,
139.3, 139.1, 138.6, 138.52, 138.47, 137.9, 137.41, 137.36, 136.0, 135.6, 134.3, 130.1,
128.8, 128.6, 128.4, 126.0, 81.0 (sp3ꢀC of C60), 67.7 (sp3ꢀC of C60), 43.6, 21.3, 19.0;
FTꢀIR ν/cmꢀ1 (KBr) 1335 (S=O), 1158 (S=O), 809 (N
–S); UVꢀvis (CHCl3) λmax/nm
(log ε) 258 (5.12), 318 (4.67), 434 (3.50), 696 (2.70); HRMS (MALDIꢀTOF) m/z
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calcd for C75H15NO2S [M]+ 993.0818, found 993.0807.
5
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7
Fullerotetrahydroquinoline 2c. By following the general procedure, the reaction of
8
9
C60
(35.8
mg,
0.05
mmol)
with
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60
Nꢀ(2ꢀ(chloromethyl)ꢀ5ꢀmethylphenyl)ꢀ4ꢀmethylbenzenesulfonamide 1c (31.0 mg,
0.10 mmol), Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (2.9 mg, 0.015 mmol) at 120
oC for 3.0 h afforded recovered C60 (21.1 mg, 59%) and 2c (14.5 mg, 29%):
1
amorphous brown solid; H NMR (400 MHz, CDCl2CDCl2) δ 7.93 (d, J = 8.2 Hz,
2H), 7.68 (s, 1H), 7.51 (d, J = 7.6 Hz, 1H), 7.38 (d, J = 7.6 Hz, 1H), 7.25 (d, J = 8.2
Hz, 2H), 4.80 (d, J = 13.7 Hz, 1H), 4.05 (d, J = 13.7 Hz, 1H), 2.55 (s, 3H), 2.33 (s,
3H); 13C NMR (100 MHz, CDCl2CDCl2) δ 155.6, 153.5, 151.0, 147.0, 146.4, 145.47,
145.45, 145.42, 145.3, 145.1, 145.04, 144.99, 144.98, 144.94, 144.85, 144.44, 144.41,
144.34, 144.32, 144.23, 144.19, 144.15, 144.11, 143.8, 143.6, 143.45, 143.42, 143.3,
143.2, 142.7, 142.4, 141.9, 141.6, 141.5, 141.45, 141.43, 141.36, 141.3, 141.14,
141.11, 141.0, 140.8, 140.47, 140.43, 140.37, 140.3, 140.1, 139.6, 139.3, 138.7, 138.3,
137.85, 137.81, 137.5, 137.0, 136.5, 135.1, 135.0, 133.7, 133.1, 129.4, 129.0, 128.7,
127.4, 127.3, 80.3 (sp3ꢀC of C60), 67.9 (sp3ꢀC of C60), 42.2, 20.7, 20.6; FTꢀIR ν/cmꢀ1
(KBr) 1337 (S=O), 1158 (S=O), 809 (N–S); UVꢀvis (CHCl3) λmax/nm (log ε) 258
(5.09), 317 (4.65), 434 (3.52), 694 (2.70); HRMS (MALDIꢀTOF) m/z calcd for
C75H15NO2S [M]+ 993.0818, found 993.0811.
Fullerotetrahydroquinoline 2d. By following the general procedure, the reaction of
C60
(35.9
mg,
0.05
mmol)
with
Nꢀ(2ꢀ(chloromethyl)ꢀ4ꢀmethylphenyl)ꢀ4ꢀmethylbenzenesulfonamide 1d (30.8 mg,
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0.10 mmol), Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (3.0 mg, 0.015 mmol) at 120
5
6
7
oC for 3.0 h afforded recovered C60 (17.4 mg, 48%) and 2d (17.1 mg, 35%):
8
9
1
amorphous brown solid; H NMR (400 MHz, CDCl2CDCl2) δ 7.91 (d, J = 8.2 Hz,
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11
12
13
14
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16
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20
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2H), 7.75 (d, J = 8.5 Hz, 1H), 7.46–7.37 (m, 2H), 7.25 (d, J = 8.2 Hz, 2H), 4.75 (d, J
13
= 13.7 Hz, 1H), 4.01 (d, J = 13.7 Hz, 1H), 2.52 (s, 3H), 2.34 (s, 3H); C NMR (100
MHz, CDCl2CDCl2) δ 155.6, 153.6, 151.2, 147.1, 146.4, 145.6, 145.49, 145.45, 145.4,
145.2, 145.1, 145.04, 145.02, 144.99, 144.9, 144.49, 144.46, 144.43, 144.39, 144.24,
144.19, 144.16, 143.8, 143.7, 143.5, 143.44, 143.36, 143.3, 142.8, 142.4, 141.9, 141.6,
141.54, 141.50, 141.47, 141.4, 141.3, 141.2, 141.10, 141.09, 140.8, 140.52, 140.48,
140.44, 140.3, 140.1, 139.7, 139.4, 138.7, 138.44, 138.38, 137.3, 137.0, 136.6, 136.0,
135.3, 135.1, 135.0, 133.8, 128.8, 128.7, 128.5, 128.4, 127.3, 80.4 (sp3ꢀC of C60), 67.8
(sp3ꢀC of C60), 42.6, 20.7; FTꢀIR ν/cmꢀ1 (KBr) 1333 (S=O), 1159 (S=O), 814 (N
–S);
UVꢀvis (CHCl3) λmax/nm (log ε) 258 (5.10), 317 (4.66), 434 (3.55), 694 (2.65); HRMS
(MALDIꢀTOF) m/z calcd for C75H15NO2S [M]+ 993.0818, found 993.0809.
Fullerotetrahydroquinoline 2e. By following the general procedure, the reaction of
C60
(35.7
mg,
0.05
mmol)
with
Nꢀ(2ꢀ(chloromethyl)ꢀ4,5ꢀdimethoxyphenyl)ꢀ4ꢀmethylbenzenesulfonamide 1e (35.5
mg, 0.10 mmol), Cu2O (1.6 mg, 0.01 mmol), and 1,10ꢀphen (3.0 mg, 0.015 mmol) at
o
120 C for 3.0 h afforded recovered C60 (18.4 mg, 52%) and 2e (18.7 mg, 36%) with
CS2/CH2Cl2 (10:1, v/v) as the eluent for silica gel column purification: amorphous
1
brown solid; H NMR (400 MHz, CDCl2CDCl2) δ 7.91 (d, J = 8.2 Hz, 2H), 7.34 (s,
1H), 7.29 (d, J = 8.2 Hz, 2H), 7.05 (s, 1H), 4.50 (d, J = 13.8 Hz, 1H), 4.00 (s, 3H),
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3.98 (s, 3H), 3.94 (d, J = 13.8 Hz, 1H), 2.37 (s, 3H); 13C NMR (100 MHz,
CDCl2CDCl2) δ 155.5, 153.5, 151.2, 148.5, 147.8, 147.1, 146.4, 145.8, 145.5, 145.4,
145.2, 145.1, 145.05, 145.02, 144.9, 144.5, 144.44, 144.38, 144.3, 144.2, 143.9,
143.64, 143.57, 143.44, 143.38, 143.3, 142.8, 142.5, 141.9, 141.7, 141.6, 141.48,
141.45, 141.4, 141.3, 141.25, 141.15, 141.1, 140.8, 140.55, 140.48, 140.3, 140.2,
139.9, 139.3, 138.7, 138.4, 136.9, 136.8, 136.6, 135.1, 135.0, 133.9, 130.3, 128.9,
128.8, 127.3, 112.6, 109.8, 80.7 (sp3ꢀC of C60), 68.1 (sp3ꢀC of C60), 55.5, 55.3, 42.3,
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29
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31
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39
40
41
42
43
44
45
46
47
48
49
50
51
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53
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56
57
58
59
60
20.8; FTꢀIR ν/cmꢀ1 (KBr) 1329 (S=O), 1160 (S=O), 810 (N
–S); UVꢀvis (CHCl3)
λmax/nm (log ε) 258 (5.09), 318 (4.62), 433 (3.51), 696 (2.65); HRMS (MALDIꢀTOF)
m/z calcd for C76H17NO4S [M]+ 1039.0873, found 1039.0862.
Fullerotetrahydroquinoline 2f. By following the general procedure, the reaction of
C60
(35.8
mg,
0.05
mmol)
with
Nꢀ(4ꢀchloroꢀ2ꢀ(chloromethyl)phenyl)ꢀ4ꢀmethylbenzenesulfonamide 1f (33.2 mg, 0.10
mmol), Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (3.1 mg, 0.015 mmol) at 140 oC for
3.0 h afforded recovered C60 (21.9 mg, 61%) and 2f (14.9 mg, 30%): amorphous
brown solid; 1H NMR (400 MHz, CDCl2CDCl2) δ 7.90 (d, J = 8.0 Hz, 2H), 7.84 (d, J
= 8.2 Hz, 1H), 7.66–7.57 (m, 2H), 7.27 (d, J = 8.0 Hz, 2H), 4.66 (d, J = 13.8 Hz, 1H),
13
4.02 (d, J = 13.8 Hz, 1H), 2.35 (s, 3H); C NMR (100 MHz, CDCl2CDCl2) δ 154.8,
153.0, 150.7, 147.1, 146.5, 145.52, 145.50, 145.4, 145.2, 145.15, 145.12, 145.08,
145.05, 144.9, 144.50, 144.49, 144.4, 144.3, 144.24, 144.20, 144.19, 144.0, 143.9,
143.8, 143.6, 143.4, 143.34, 143.28, 142.5, 142.2, 141.9, 141.65, 141.57, 141.55,
141.51, 141.45, 141.25, 141.19, 141.17, 141.12, 141.07, 140.9, 140.55, 140.52,
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140.48, 140.3, 140.1, 139.7, 139.4, 138.8, 138.5, 138.0, 137.2, 136.70, 136.68, 136.6,
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6
7
134.97, 134.95, 133.8, 133.6, 130.6, 128.9, 128.0, 127.8, 127.3, 80.4 (sp3ꢀC of C60),
8
9
67.6 (sp3ꢀC of C60), 42.3, 20.8; FTꢀIR ν/cmꢀ1 (KBr) 1334 (S=O), 1158 (S=O)816 (N
S), 662 (C Cl); UVꢀvis (CHCl3) λmax/nm (log ε) 258 (5.09), 318 (4.64), 433 (3.45),
–
10
11
12
13
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43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
–
691 (2.70); HRMS (MALDIꢀTOF) m/z calcd for C74H12NO2S35Cl [M]+ 1013.0272,
found 1013.0259.
Fullerotetrahydroquinoline 2g. By following the general procedure, the reaction of
C60
(35.6
mg,
0.05
mmol)
with
Nꢀ(2ꢀ(chloro(phenyl)methyl)phenyl)ꢀ4ꢀmethylbenzenesulfonamide 1g (37.2 mg, 0.10
mmol), Cu2O (3.6 mg, 0.025 mmol), and 1,10ꢀphen (7.3 mg, 0.0375 mmol) at 140 oC
for 6.0 h afforded recovered C60 (24.0 mg, 67%) and 2g (10.5 mg, 20%): amorphous
brown solid; 1H NMR (400 MHz, CDCl2CDCl2) δ 8.00 (d, J = 7.7 Hz, 1H), 7.93 (d, J
= 8.2 Hz, 2H), 7.71 (d, J = 7.7 Hz, 1H), 7.66 (t, J = 7.6 Hz, 1H), 7.55 (t, J = 7.6 Hz,
1H), 7.38–7.19 (m, 7H), 5.80 (s, 1H), 2.40 (s, 3H); 13C NMR (100 MHz,
CDCl2CDCl2) δ 152.1, 151.3, 151.1, 146.9, 146.4, 146.3, 145.5, 145.45, 145.43,
145.37, 145.3, 145.02, 144.98, 144.9, 144.7, 144.45, 144.44, 144.40, 144.3, 144.24,
144.17, 144.14, 144.09, 144.06, 144.0, 143.7, 143.4, 143.33, 143.27, 143.24, 142.4,
141.8, 141.6, 141.48, 141.46, 141.4, 141.3, 141.2, 141.1, 140.9, 140.8, 140.7, 140.5,
140.2, 140.0, 139.9, 139.7, 138.7, 137.9, 137.6, 137.5, 137.0, 136.5, 136.0, 134.8,
134.6, 134.0, 132.8, 129.5, 129.0, 127.8, 127.5, 127.3, 127.2, 126.5, 81.4 (sp3ꢀC of
C60), 73.2 (sp3ꢀC of C60), 54.7, 20.6; FTꢀIR ν/cmꢀ1 (KBr) 1339 (S=O), 1162 (S=O),
810 (N
–
S); UVꢀvis (CHCl3) λmax/nm (log ε) 258 (5.12), 319 (4.71), 434 (3.49), 694
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(2.65); HRMS (MALDIꢀTOF) m/z calcd for C80H17NO2S [M]+ 1055.0975, found
1055.0992.
7
8
9
Fullerotetrahydroquinoline 2h. By following the general procedure, the reaction of
C60 (35.6 mg, 0.05 mmol) with Nꢀ(2ꢀ(chloromethyl)phenyl)benzenesulfonamide 1h
(28.4 mg, 0.10 mmol), Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (2.9 mg, 0.015
10
11
12
13
14
15
16
17
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19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
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40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
o
mmol) at 120 C for 3.0 h afforded recovered C60 (18.9 mg, 53%) and 2h (16.1 mg,
1
34%): amorphous brown solid; H NMR (400 MHz, CDCl2CDCl2) δ 8.05 (d, J = 7.3
Hz, 2H), 7.88 (d, J = 7.5 Hz, 1H), 7.66–7.56 (m, 3H), 7.55–7.43 (m, 3H), 4.82 (d, J =
13.7 Hz, 1H), 4.08 (d, J = 13.7 Hz, 1H); 13C NMR (100 MHz, CDCl2CDCl2) δ 155.2,
153.3, 150.8, 147.0, 146.3, 145.43, 145.37, 145.3, 145.2, 145.1, 144.99, 144.95,
144.93, 144.92, 144.8, 144.41, 144.37, 144.35, 144.14, 144.10, 144.06, 143.8, 143.6,
143.4, 143.22, 143.15, 142.6, 142.2, 141.8, 141.54, 141.47, 141.44, 141.40, 141.3,
141.2, 141.06, 141.02, 141.00, 140.7, 140.43, 140.40, 140.32, 140.26, 139.9, 139.5,
139.3, 138.7, 138.3, 137.9, 137.5, 136.6, 136.3, 135.0, 134.9, 133.6, 132.2, 128.9,
128.2, 128.1, 127.74, 127.72, 127.2, 80.3 (sp3ꢀC of C60), 67.8 (sp3ꢀC of C60), 42.5;
FTꢀIR ν/cmꢀ1 (KBr) 1328 (S=O), 1156 (S=O), 820 (N
–S); UVꢀvis (CHCl3) λmax/nm
(log ε) 258 (5.13), 318 (4.69), 433 (3.50), 696 (2.70); HRMS (MALDIꢀTOF) m/z
calcd for C73H11NO2S [M]+ 965.0505, found 965.0516.
Fullerotetrahydroquinoline 2i. By following the general procedure, the reaction of
C60
(36.0
mg,
0.05
mmol)
with
Nꢀ(2ꢀ(chloromethyl)phenyl)ꢀ2ꢀmethylbenzenesulfonamide 1i (30.0 mg, 0.10 mmol),
o
Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (2.9 mg, 0.015 mmol) at 120 C for 3.0 h
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afforded recovered C60 (21.5 mg, 60%) and 2i (15.8 mg, 32%): amorphous brown
5
6
7
1
solid; H NMR (400 MHz, CDCl2CDCl2) δ 8.17 (d, J = 7.5 Hz, 1H), 7.95–7.89 (m,
8
9
1H), 7.70–7.66 (m, 1H), 7.65–7.57 (m, 2H), 7.36 (t, J = 7.5 Hz, 1H), 7.26–7.18 (m,
2H), 5.44 (d, J = 13.8 Hz, 1H), 4.17 (d, J = 13.8 Hz, 1H), 2.92 (s, 3H); 13C NMR (100
MHz, CDCl2CDCl2) δ 155.7, 153.5, 151.0, 147.1, 146.4, 145.5, 145.4, 145.3, 145.1,
145.04, 145.02, 144.98, 144.95, 144.5, 144.4, 144.22, 144.18, 144.1, 143.8, 143.72,
143.66, 143.5, 143.3, 143.2, 142.7, 142.1, 141.8, 141.6, 141.51, 141.46, 141.44,
141.38, 141.2, 141.15, 141.06, 141.03, 141.00, 140.8, 140.5, 140.3, 140.0, 139.42,
139.37, 138.7, 138.34, 138.26, 137.9, 137.7, 137.4, 137.1, 136.6, 135.1, 135.0, 133.6,
132.7, 131.8, 131.2, 129.0, 128.3, 128.2, 127.7, 125.3, 80.5 (sp3ꢀC of C60), 67.5
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41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(sp3ꢀC of C60), 42.7, 20.1; FTꢀIR ν/cmꢀ1 (KBr) 1328 (S=O), 1157 (S=O), 822 (N
–S);
UVꢀvis (CHCl3) λmax/nm (log ε) 258 (5.05), 318 (4.62), 434 (3.45), 697 (2.65); HRMS
(MALDIꢀTOF) m/z calcd for C74H13NO2S [M]+ 979.0662, found 979.0646.
Fullerotetrahydroquinoline 2j. By following the general procedure, the reaction of
C60
(35.8
mg,
0.05
mmol)
with
Nꢀ(2ꢀ(chloromethyl)phenyl)ꢀ3ꢀmethylbenzenesulfonamide 1j (29.4 mg, 0.10 mmol),
o
Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (2.9 mg, 0.015 mmol) at 120 C for 3.0 h
afforded recovered C60 (21.7 mg, 61%) and 2j (15.3 mg, 31%): amorphous brown
solid; 1H NMR (400 MHz, CS2 with DMSOꢀd6 as the external reference) δ 7.62–7.55
(m, 3H), 7.43–7.29 (m, 3H), 7.18–7.07 (m, 2H), 4.43 (d, J = 13.6 Hz, 1H), 3.77 (d, J
= 13.6 Hz, 1H), 2.19 (s, 3H); 13C NMR (100 MHz, CS2 with DMSOꢀd6 as the external
reference) δ 156.0, 154.0, 151.8, 147.5, 146.9, 146.5, 145.99, 145.96, 145.9, 145.7,
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145.6, 145.52, 145.50, 145.3, 145.1, 145.02, 145.00, 144.9, 144.73, 144.72, 144.67,
144.66, 144.5, 144.1, 143.93, 143.88, 143.86, 143.2, 143.0, 142.5, 142.13, 142.11,
142.05, 142.0, 141.9, 141.8, 141.73, 141.68, 141.6, 141.3, 141.1, 141.0, 140.9, 140.5,
140.3, 139.9, 139.3, 138.94, 138.88, 138.4, 137.7, 137.2, 136.7, 135.8, 135.5, 134.4,
132.8, 129.8, 128.5, 128.35, 128.28, 128.1, 127.8, 124.9, 80.6 (sp3ꢀC of C60), 68.4
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44
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46
47
48
49
50
51
52
53
54
55
56
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58
59
60
(sp3ꢀC of C60), 43.0, 21.0; FTꢀIR ν/cmꢀ1 (KBr) 1339 (S=O), 1162 (S=O), 818 (N
–S);
UVꢀvis (CHCl3) λmax/nm (log ε) 258 (5.02), 318 (4.57), 434 (3.39), 696 (2.60); HRMS
(MALDIꢀTOF) m/z calcd for C74H13NO2S [M]+ 979.0662, found 979.0651.
Fullerotetrahydroquinoline 2k. By following the general procedure, the reaction of
C60
(35.7
mg,
0.05
mmol)
with
Nꢀ(2ꢀ(chloromethyl)phenyl)ꢀ4ꢀmethoxybenzenesulfonamide 1k (31.0 mg, 0.10 mmol),
o
Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (3.0 mg, 0.015 mmol) at 140 C for 5.0 h
afforded recovered C60 (23.5 mg, 66%) and 2k (12.6 mg, 26%) with CS2/CH2Cl2
(10:1, v/v) as the eluent for silica gel column purification: amorphous brown solid; 1H
NMR (400 MHz, CDCl2CDCl2) δ 7.97 (d, J = 9.0 Hz, 2H), 7.90–7.85 (m, 1H), 7.66–
7.55 (m, 3H), 6.92 (d, J = 9.0 Hz, 2H), 4.84 (d, J = 13.7 Hz, 1H), 4.09 (d, J = 13.7 Hz,
1H), 3.78 (s, 3H); 13C NMR (100 MHz, CDCl2CDCl2) δ 162.2, 155.5, 153.4, 151.1,
147.1, 146.4, 145.54, 145.47, 145.4, 145.3, 145.2, 145.1, 145.01, 145.00, 144.97,
144.8, 144.44, 144.40, 144.39, 144.3, 144.22, 144.20, 144.1, 143.8, 143.6, 143.4,
143.31, 143.25, 142.7, 142.4, 141.9, 141.6, 141.52, 141.49, 141.45, 141.40, 141.3,
141.13, 141.08, 141.05, 140.8, 140.51, 140.45, 140.4, 140.3, 140.1, 139.7, 139.4,
138.7, 138.4, 138.2, 137.2, 136.7, 136.2, 135.0, 133.7, 131.4, 129.5, 129.1, 128.2,
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127.80, 127.76, 113.4, 80.3 (sp3ꢀC of C60), 67.9 (sp3ꢀC of C60), 54.9, 42.5; FTꢀIR
5
6
7
ν/cmꢀ1 (KBr) 1327 (S=O), 1152 (S=O), 828 (N
–S); UVꢀvis (CHCl3) λmax/nm (log ε)
8
9
257 (5.13), 318 (4.66), 434 (3.50), 697 (2.70); HRMS (MALDIꢀTOF) m/z calcd for
C74H13NO3S [M]+ 995.0611, found 995.0601.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
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27
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44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fullerotetrahydroquinoline 2l. By following the general procedure, the reaction of
C60
(35.9
mg,
0.05
mmol)
with
4ꢀchloroꢀNꢀ(2ꢀ(chloromethyl)phenyl)benzenesulfonamide 1l (31.4 mg, 0.10 mmol),
o
Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (3.0 mg, 0.015 mmol) at 120 C for 3.0 h
afforded recovered C60 (23.9 mg, 67%) and 2l (15.1 mg, 30%): amorphous brown
1
solid; H NMR (400 MHz, CDCl2CDCl2) δ 8.03 (d, J = 8.6 Hz, 2H), 7.90 (d, J = 7.5
Hz, 1H), 7.72–7.61 (m, 3H), 7.50 (d, J = 8.6 Hz, 2H), 4.82 (d, J = 13.8 Hz, 1H), 4.15
(d, J = 13.8 Hz, 1H); 13C NMR (100 MHz, CDCl2CDCl2) δ 155.1, 153.2, 150.6, 147.0,
146.4, 145.5, 145.4, 145.3, 145.13, 145.09, 145.03, 144.99, 144.97, 144.9, 144.5,
144.41, 144.39, 144.3, 144.18, 144.15, 144.09, 144.07, 144.0, 143.8, 143.6, 143.4,
143.24, 143.18, 142.5, 142.1, 141.9, 141.6, 141.52, 141.48, 141.45, 141.38, 141.2,
141.1, 141.04, 141.02, 140.8, 140.5, 140.44, 140.43, 140.3, 139.9, 139.6, 139.4, 138.8,
138.7, 138.6, 138.4, 137.8, 137.4, 136.7, 136.2, 135.1, 134.9, 133.6, 128.9, 128.5,
128.3, 127.8, 127.7, 80.5 (sp3ꢀC of C60), 67.8 (sp3ꢀC of C60), 42.6; FTꢀIR ν/cmꢀ1 (KBr)
1346 (S=O), 1163 (S=O), 820 (N–S), 740 (C–Cl); UVꢀvis (CHCl3) λmax/nm (log ε) 258
(5.09), 318 (4.64), 433 (3.46), 697 (2.74); HRMS (MALDIꢀTOF) m/z calcd for
C73H10NO2S35Cl [M]+ 999.0115, found 999.0107.
Fullerotetrahydroquinoline 2m. By following the general procedure, the reaction of
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C60
(35.8
mg,
0.05
mmol)
with
5
6
7
Nꢀ(2ꢀ(chloromethyl)phenyl)ꢀ4ꢀnitrobenzenesulfonamide 1m (32.5 mg, 0.10 mmol),
8
9
o
Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (3.0 mg, 0.015 mmol) at 140 C for 5.0 h
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
afforded recovered C60 (22.1 mg, 62%) and 2m (13.9 mg, 28%) with CS2/CH2Cl2
(10:1, v/v) as the eluent for silica gel column purification: amorphous brown solid; 1H
NMR (400 MHz, CDCl2CDCl2) δ 8.31 (d, J = 8.9 Hz, 2H), 8.26 (d, J = 8.9 Hz, 2H),
7.91–7.86 (m, 1H), 7.71–7.60 (m, 3H), 4.78 (d, J = 13.8 Hz, 1H), 4.15 (d, J = 13.8 Hz,
1H); 13C NMR (100 MHz, CDCl2CDCl2) δ 154.8, 153.1, 150.1, 148.9, 147.1, 146.4,
145.9, 145.6, 145.5, 145.3, 145.2, 145.10, 145.08, 145.06, 145.02, 144.53, 144.47,
144.44, 144.30, 144.26, 144.13, 144.06, 144.0, 143.9, 143.8, 143.7, 143.5, 143.3,
143.1, 142.5, 141.9, 141.8, 141.7, 141.6, 141.54, 141.52, 141.47, 141.2, 141.14,
141.08, 141.0, 140.9, 140.6, 140.50, 140.49, 140.3, 140.0, 139.5, 138.8, 138.5, 137.9,
137.3, 136.6, 136.3, 135.3, 134.7, 133.5, 128.8, 128.7, 128.5, 128.13, 128.11, 123.3,
80.9 (sp3ꢀC of C60), 67.7 (sp3ꢀC of C60), 42.6; FTꢀIR ν/cmꢀ1 (KBr) 1514 (NO2), 1336
(S=O), 1164 (S=O), 826 (N–S); UVꢀvis (CHCl3) λmax/nm (log ε) 257 (5.01), 318
(4.56), 434 (3.33), 695 (2.65); HRMS (MALDIꢀTOF) m/z calcd for C73H10N2O4S
[M]+ 1010.0356, found 1010.0342.
Fullerotetrahydroquinoline 2n. By following the general procedure, the reaction of
C60 (35.9 mg, 0.05 mmol) with Nꢀ(2ꢀ(chloromethyl)phenyl)thiopheneꢀ2ꢀsulfonamide
1n (28.9 mg, 0.10 mmol), Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (3.1 mg, 0.015
o
mmol) at 140 C for 3.0 h afforded recovered C60 (22.6 mg, 63%) and 2n (16.2 mg,
1
33%): amorphous brown solid; H NMR (400 MHz, CDCl2CDCl2) δ 7.87 (d, J = 7.4
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Hz, 1H), 7.75–7.70 (m, 1H), 7.69–7.55 (m, 4H), 7.03 (t, J = 4.4 Hz, 1H), 4.66 (d, J =
13.8 Hz, 1H), 4.10 (d, J = 13.8 Hz, 1H); 13C NMR (100 MHz, CDCl2CDCl2) δ 155.2,
153.3, 150.6, 147.1, 146.4, 145.5, 145.4, 145.3, 145.2, 145.07, 145.05, 145.02, 144.99,
144.9, 144.5, 144.44, 144.39, 144.23, 144.17, 144.15, 144.13, 144.11, 143.8, 143.6,
143.4, 143.30, 143.26, 142.7, 142.5, 141.9, 141.6, 141.53, 141.46, 141.4, 141.3, 141.2,
141.1, 141.0, 140.9, 140.8, 140.54, 140.45, 140.44, 140.3, 140.0, 139.7, 139.3, 138.7,
138.3, 137.9, 137.3, 136.8, 135.9, 135.08, 135.07, 133.64, 133.57, 133.2, 129.2, 128.4,
127.9, 127.8, 126.7, 80.7 (sp3ꢀC of C60), 67.9 (sp3ꢀC of C60), 42.4; FTꢀIR ν/cmꢀ1 (KBr)
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
1346 (S=O), 1159 (S=O), 821 (N–S); UVꢀvis (CHCl3) λmax/nm (log ε) 258 (5.06), 318
(4.61), 433 (3.41), 695 (2.60); HRMS (MALDIꢀTOF) m/z calcd for C71H9NO2S2 [M]+
971.0069, found 971.0056.
Fullerotetrahydroquinoline 2o. By following the general procedure, the reaction of
C60 (35.6 mg, 0.05 mmol) with Nꢀ(2ꢀ(chloromethyl)phenyl)methanesulfonamide 1o
(21.8 mg, 0.10 mmol), Cu2O (1.5 mg, 0.01 mmol), and 1,10ꢀphen (3.0 mg, 0.015
o
mmol) at 120 C for 3.0 h afforded recovered C60 (23.6 mg, 66%) and 2o (13.1 mg,
1
29%): amorphous brown solid; H NMR (400 MHz, CDCl2CDCl2) δ 7.72–7.63 (m,
2H), 7.62–7.53 (m, 2H), 5.09 (d, J = 13.7 Hz, 1H), 4.23 (d, J = 13.7 Hz, 1H), 3.58 (s,
3H); 13C NMR (100 MHz, CDCl2CDCl2) δ 155.0, 153.2, 150.9, 147.1, 146.5, 145.6,
145.5, 145.4, 145.2, 145.12, 145.08, 145.04, 144.9, 144.6, 144.5, 144.44, 144.42,
144.3, 144.22, 144.15, 144.1, 143.92, 143.87, 143.8, 143.5, 143.34, 143.26, 142.7,
142.2, 142.0, 141.7, 141.6, 141.52, 141.45, 141.22, 141.20, 141.15, 141.1, 140.9,
140.7, 140.6, 140.40, 140.36, 140.1, 140.0, 139.4, 138.9, 138.7, 138.6, 138.5, 137.7,
29
ACS Paragon Plus Environment