N-Hydroxyphthalimide-Catalyzed Carboxylation of Polycyclic Alkanes with Carbon Monoxide in the Presence of Dioxygen

Full text of DOI:10.1021/jo9718556

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J . Org. Chem. 1998, 63, 222-223
N-Hyd r oxyp h th a lim id e-Ca ta lyzed
Ca r boxyla tion of P olycyclic Alk a n es w ith
Ca r bon Mon oxid e in th e P r esen ce of
Dioxygen
Ta ble 1. Ca r boxyla tion of Ad a m a n ta n e (1) Ca ta lyzed by
NHP Ia
selectivity/%
3b
run CO/atm air/atm conv/%
2
4
5
6
7
1
2
3
4
5
6
7
8
15
15
15
15
15
15
5
15
15
15
1
69
78
55
trace
no reaction
7
4
8
54
2
5
2
4
Susumu Kato, Takahiro Iwahama,
Satoshi Sakaguchi, and Yasutaka Ishii*
1c
d
e
f
1
1
1
1
1
1
1
75
79
62
63
69
76
56
40
40
38
35
41
8
7
4
2
4
7
5
3
4
3
3
4
4
8
13
16
9
3
3
1
5
3
3
2
2
2
3
4
Department of Applied Chemistry, Faculty of Engineering &
High Technology Research Center, Kansai University, Suita,
Osaka 564, J apan
g
Received October 8, 1997
9h
10
i
1
0
no reaction
Carbonylation as well as carboxylation of saturated
hydrocarbons with carbon monoxide (CO) are challenging
a
Substrate (1 mmol) was allowed to react under carbon
monoxide/air in the presence of NHPI (10 mol %) in acetic acid (3
mL) and 1,2-dichloroethane (3 mL) at 95 °C for 4 h. Yield of 3
subjects in organic synthesis, since they are very difficult
b
to carry out selectively.1 The introduction of CO into
was estimated as dimethylester after esterfication with excess
unreactive carbon-hydrogen bonds has been reported to be
methanol. c O2 was used in place of air. d In a mixed solvent of
2
-5
6
achieved by transition metals,
Lewis and superacids, and
e
acetic acid (1 mL) and 1,2-dichloroethane (5 mL). 60 °C, 15 h.
radical species.7
-10
For example, alkanes such as n-pentane
f
g
N-Hydroxysuccinimide was used in place of NHPI. In acetic acid
were carbonylated with CO by a Rh complex under photo-
6 mL). h In acetonitrile (6 mL). In the presence of hydroquinone
i
(
2
chemical conditions. Methane and ethane are carboxylated
(0.1 mol %).
3
4
with CO by Pd/Cu and RhCl3 in the presence of molecular
oxygen. Under the influence of superacids such as SbF5/
Sch em e 1. P la u sible Rea ction P a th for th e
NHP I-Ca ta lyzed F r ee-Ra d ica l Ca r boxyla tion of
Ad a m a n ta n e (1) w ith CO/Air
CF3SO3H6b and CH2Br2/2AlCl3,6e adamantane was converted
into adamantanecarboxylic acid and/or adamantanecarbal-
dehyde.
On the other hand, the carbonylation mediated by a free
1
1
radical was first reported by Coffmann et al. in 1952, but
this type of reaction was not extensively studied for a long
time probably because the reaction was conducted under
extremely high CO pressure (200-3000 atm).12 However,
since the successful free-radical carbonylation of alkyl
halides with CO mediated by tin hydride was reported by
Ryu et al., the radical carbonylation of alkanes has been
examined in recent years.13 Sen et al. have disclosed the
free-radical carboxylation of methane to acetic acid by the
use of peroxydisulfate as a radical source.7 Benzophenone-8
(
1) For recent reviews: (a) Barton, D. H. R.; Doller, D. Acc. Chem. Res.
1
992, 25, 504. (b) Sommer, J .; Bukala, J . Acc. Chem. Res. 1993, 26, 370. (c)
Arndtsen, B. A.; Bergman, R. G.; Mobley, T. A.; Peterson, T. H. Acc. Chem.
Res. 1995, 28, 154. (d) Hill, C. L. Synlett 1995, 127. (e) Ryu, I.; Sonoda, N.
Angew. Chem., Int. Ed. Engl. 1996, 35, 1051.
(2) (a) Sakakura, T.; Sodeyama, T.; Sasaki, K.; Wada, K.; Tanaka, M. J .
Am. Chem. Soc. 1990, 112, 7221. (b) Margl, P.; Ziegler, T.; Bl o¨ chl, P. E. J .
Am. Chem. Soc. 1996, 118, 5412.
(
3) (a) Satoh, K.-I.; Watanabe, J .; Takaki, K.; Fujiwara, Y. Chem. Lett.
1
991, 1433. (b) Nakata, K.; Miyata, T.; J intoku, T.; Kitani, A.; Taniguchi,
Y.; Takaki, K.; Fujiwara, Y. Bull. Chem. Soc. J pn. 1993, 66, 3755. (c)
Nakata, K.; Yamaoka, Y.; Miyata, T.; Taniguchi, Y.; Takaki, K.; Fujiwara,
Y. J . Organomet. Chem. 1994, 437, 329. (d) Fujiwara, Y.; Takaki, K.;
Taniguchi, Y. Synlett 1996, 591 and references cited therein.
(
4) (a) Lin, M.; Sen, A. Nature 1994, 368, 613. (b) Lin, M.; Hogan, T. E.;
Sen, A. J . Am. Chem. Soc. 1996, 118, 4574.
5) (a) Barton, D. H. R.; Csuhai, E.; Doller, D. Tetrahedron Lett. 1992,
3, 4389. (b) Barton, D. H. R. Synlett 1997, 229.
6) (a) Koch, H.; Haaf, W. Organic Syntheses; Wiley: New York, 1973;
(
3
(
Collect. Vol. V, p 20. (b) Takeuchi, K.-I.; Akiyama, F.; Miyazaki, T.;
Kitagawa, I.; Okamoto, K. Tetrahedron 1987, 43, 701. (c) Farooq, O.;
Marcelli, M.; Prakash, G. K. S.; Olah, G. A. J . Am. Chem. Soc. 1988, 110,
8
1
64. (d) Akhrem, I. S.; Bernadyuk, S. Z.; Vol’pin, M. E. Mendeleev Commun.
993, 188. (e) Akhrem, I. S.; Churilova, I. M.; Orlinkov, A. V.; Vol’pin, M.
and polyoxotungstate-photocatalyzed9 and mercury-photo-
sensitized carbonylations of cyclohexane afford cyclohex-
10
E. Russ. Chem. Bull. 1997, 46, 491.
7) Sen, A.; Lin, M. J . Chem. Soc., Chem. Commun. 1992, 892.
anecarboaldehyde in fair yields. These reactions, however,
are limited to being carryied out on a synthetic scale, since
the conversion of alkanes is not high.
Recently, we showed that the aerobic oxidation of
14a,f
14b
14c-e
alkylbenzenes,
alcohols,
and alkanes
was effi-
1
1
958, 80, 2882. (b) Walling, C.; Savas, E. S. J . Am. Chem. Soc. 1960, 82,
738. (c) Thaler, W. A. J . Am. Chem. Soc. 1966, 88, 4278. (d) Thaler, W. A.
(13) (a) Ryu, I.; Kusano, K.; Ogawa, A.; Kambe, N.; Sonoda, N. J . Am.
Chem. Soc. 1990, 112, 1295. (b) Ryu, I.; Sonoda, N. Chem. Rev. (Washington,
D.C.) 1996, 96, 177. (c) Nagahara, K.; Ryu, I.; Komatsu, M.; Sonoda, N. J .
Am. Chem. Soc. 1997, 119, 5465.
1
J . Am. Chem. Soc. 1967, 89, 1902. (e) Susuki, T.; Tsuji, J . J . Org. Chem.
970, 35, 2982.
1
S0022-3263(97)01855-0 CCC: $15.00 © 1998 American Chemical Society
Published on Web 01/07/1998

Communications
J . Org. Chem., Vol. 63, No. 2, 1998 223
ciently promoted by N-hydroxyphthalimide (NHPI) com-
bined with a small amount of transition metal salts to
produce the corresponding oxygenated products. We have
now developed a new type of catalytic free-radical carboxyl-
ation of polycyclic alkanes such as adamantanes with CO/
air using N-hydroxyphthalimide (NHPI), which serves as an
efficient radical catalyst. In this paper, we report the
catalytic free-radical carboxylation of alkanes by NHPI
without any photoactivation under mild conditions, i.e.,
lower CO pressure (up to 15 atm) and temperature (below
present carboxylation of 1 was efficiently catalyzed by NHPI
alone under mild conditions.
The carboxylation of 2 in the presence of NHPI (30 mol
%) gave dicarboxylic acid 3 in 57% yield at 74% conversion
(eq 2, Supporting Information). The formation of 3 is
interesting from a synthetic point of view, because dicar-
boxylic acid 3 is difficult to obtain from the conventional
carboxylation of 1 with CO.
Similarly, 1,3-dimethyladamantane was also carboxylated
under these conditions to give the corresponding adamantyl
monocarboxylic acid (55%) and dicarboxylic acid (7%) in 77%
conversion (eq 3, Supporting Information). The carboxyla-
tion of endo-tricyclo[5.2.1.02 ]decane (9) by NHPI (30 mol
%) combined with a slight amount of Co(acac)2 (0.5 mol %)
gave monocarboxylic acid 10 as the major product (55%) (eq
4, Supporting Information). The same reaction of 9 in the
absence of Co(acac)2 resulted in the lowering of the yield of
10.
1
00 °C).
A typical reaction was carried out as follows. To a solution
,6
of NHPI (0.1 mmol) in a mixed solvent of acetic acid (3 mL)
and 1,2-dichloroethane (3 mL) in a glass-lining autoclave
was added adamantane (1) (1 mmol), and then 1 atm of air
and 15 atm of CO was charged. The reaction was carried
out at 95 °C for 4 h. Table 1 shows the representative
results for the carboxylation of 1 under various reaction
conditions.
A plausible mechanism of the present NHPI-catalyzed
radical carboxylation of 1 with CO/air system is outlined in
Scheme 1. The first step is the generation of phthalimide-
N-oxyl (PINO) from NHPI with O2.1 The PINO abstracts
a tertiary hydrogen from 1 to form an adamantyl radical
4d
(
A), which is the key intermediate in this reaction. It is
1
e
probable that the radical A is readily trapped with CO,
giving adamantaneformyl radical (B), which on subsequent
reaction with O2, produces adamantanecarboperoxy radical
(C) and eventually carboxylic acid 2.
To clarify the participation of the acyladamantyl cation
The carboxylation of 1 with CO/air in the presence of
NHPI gave 1-adamantanecarboxylic acid (2), 1,3-adaman-
tanedicarboxylic acid (3), 2-adamantanecarboxylic acid (4),
and several oxygenated products such as 1-adamantanol (5)
and 2-adamantanone (6) as well as 1-acetoxyadamantane
in the formation of carboxylic acid 2, the carboxylation of 1
in the presence of H218O was examined under the same
conditions as run 1 in Table 1. The mass spectrum of the
1
8
resulting 2 showed that the ratio of 2/ O labeled-2 is 94/6.
This suggests that most of the carboxyl oxygen contained
(7). Although the selectivity of these products depended
1
8
in 2 comes from CO and air, but not from H2 O. If the
NHPI-catalyzed carboxylation of 1 passes through the
acyladamantyl cation as a transient intermediate, a consid-
erable amount of 2 in which 18O was incorporated in the
molecule should be formed.
markedly on the reaction conditions, 1-adamantanecarb-
aldehyde (8) was not formed in all reactions examined.
When the reaction was carried out using molecular oxygen
in place of air, oxidative products were formed as major
products (run 2). Needless to say, the reaction did not take
place without air (run 3). Among the solvents examined, a
mixed solvent consisting of acetic acid and 1,2-dichloro-
ethane (1/5 v/v %) gave the best yield of 2 (56%) at 75%
conversion (run 4). The present reaction proceeded even at
In addition, the reaction of 1-bromoadamantane (12) with
CO/air by the Ryu system using AIBN/Bu3SnH,13 which can
be excluded the formation of the acyladamantyl cation as
the intermediate, gave also 2 in 54% yield (eq 5). These
6
0 °C, although a prolonged reaction time was necessary to
obtain satisfactory yield of 2 (run 5). The carboxylation of
using N-hydroxysuccinimide, an analogue of NHPI, under
these conditions gave 2 in slightly lower selectivity (40%)
1
(run 6).
The reaction did not take place in the presence of
observations suggest that the NHPI-catalyzed carboxylation
of 1 under the influence of CO/air proceeds through the
acyladamantyl radical rather than the acyladamantyl cation.
Although a part of the C seems to decompose to adamantyl
radical A, carbon dioxide, and dioxygen, the resulting A can
also react with CO to regenerate the B.
The fact that no aldehyde 8 was formed in the present
reaction may indicate that the 8 formed is rapidly converted
into carboxylic acid 2 under these conditions. In fact, the
independent reaction of 8 under the influence of NHPI and
CO/air gave 2 in 57% yield along with adamantane 1 (12%),
hydroquinone (0.1 mol %) (run 10). This shows that the
NHPI-catalyzed carboxylation involves the radical process
in the reaction step. In the present carboxylation of 1, the
relative reactivity of the tertiary hydrogen to the secondary
hydrogen estimated from run 1 was ca. 12.15 This value was
almost the same as that by the NHPI-catalyzed aerobic
oxidation of 1,1 which may reflect a reaction path in the
present carboxylation analogous to that of the aerobic
oxidation reported previously.
4c
In contrast to the NHPI-catalyzed aerobic oxidation of
alkanes where the reaction is markedly enhanced by the
addition of a transition metal salt such as Co(acac)2, the
1
6
-adamantanol 5 (5%), and 1-acetoxyadamantane 7 (1%) (eq
). The formation of 1, 5 and 7 from 8 suggests that the
reaction between 1 and 8 is reversible path.
(14) In a previous paper, we demonstrated that PINO is easily generated
by exposing NHPI to molecular oxygen. (a) Ishii, Y.; Nakayama, K.; Takeno,
M.; Sakaguchi, S.; Iwahama, T.; Nishiyama, Y. J . Org. Chem. 1995, 60,
Ack n ow led gm en t. This work was partly supported by
Grant-in-Aid for Scientific Research (No.09238255) on
Priority Areas (No. 283, “Innovative Synthetic Reactions”
from Monbusho.
3
934. (b) Iwahama, T.; Sakaguchi, S.; Nishiyama, Y.; Ishii, Y. Tetrahedron
Lett. 1995, 36, 6923. (c) Ishii, Y.; Kato, S.; Iwahama, T.; Sakaguchi, S.
Tetrahedron Lett. 1996, 37, 4993. (d) Ishii, Y.; Iwahama, T.; Sakaguchi, S.;
Nakayama, K.; Nishiyama, Y. J . Org. Chem. 1996, 61, 4520. (e) Ishii, Y. J .
Mol. Catal. A: Chem. 1997, 123. (f) Yoshino, Y.; Hayashi, Y.; Iwahama, T.;
Sakaguchi, S.; Ishii, Y. J . Org. Chem. 1997, 62, 6810.
Su p p or tin g In for m a tion Ava ila ble: Equations 2-4 and 6
characterization data for all compounds (16 pages).
3
°
2°
(
15) The ratio of C -H/C -H was estimated from total yield of 2, 3, 5,
and 7/total yield of 4 and 6.
J O9718556