Indium(III)-catalyzed addition of 1,3-dicarbonyl compounds to alkenes

Article abstract of DOI:10.1055/s-2007-992388

A new InCl₃-catalyzed addition reaction of 1,3-dicarbonyl compounds to various alkenes proceeded in good yields and can be carried out in air, which provided an easy and practical procedure for carbon-carbon bond formation. Georg Thieme Verlag Stuttgart.

Full text of DOI:10.1055/s-2007-992388

LETTER
3219
Indium(III)-Catalyzed Addition of 1,3-Dicarbonyl Compounds to Alkenes
I
ndium(III)-Cataly
u
zedAdditionof 1,3
Y
-Dicarbonyl Com
u
poundstoA
l
a
kenes n,* Zhuangzhi Shi
College of Chemistry & Chemical Engineering, Yangzhou University, 225002 Yangzhou, P. R. of China
Fax +86(514)7975244; E-mail: yyuan@yzu.edu.cn
Received 14 September 2007
lenic 1,3-dicarbonyl compounds. The intermolecular
additions of active methylene compounds to alkynes were
reported by Takai10 and Nakamura11 using rhenium and
indium Lewis acids, respectively. Recently, Wu devel-
oped the addition of activated methylene to styrene deriv-
atives using FeCl3 as the catalyst.12 Kaneda found that the
addition reaction of various 1,3-dicarbonyl compounds to
alkenes in the presence of solid acid catalysts proceeded
in good yield.13 Herein, we report the use of InCl3 as a cat-
alyst to promote a highly efficient intermolecular addition
of 1,3-dicarbonyl compounds to alkenes.
Abstract: A new InCl3-catalyzed addition reaction of 1,3-dicarbo-
nyl compounds to various alkenes proceeded in good yields and can
be carried out in air, which provided an easy and practical procedure
for carbon–carbon bond formation.
Key words: addition, indium, catalysis, alkene
The formation of carbon–carbon bonds is one of the most
important reactions for the construction of molecular
frameworks in organic chemistry.1 In recent years, much
attention has been paid to the functionalization of activat-
ed methylene compounds, such as 1,3-dicarbonyl com-
pounds, by catalytic nucleophilic substitution.2 However,
significant goals of green chemistry are to maximize the
efficiency of the reaction, to minimize the creation of
waste and to use environmentally benign catalysts.3 Sub-
stitution reactions are less atom-economical than addition
reactions in terms of atom efficiency, because substitution
reactions invariably generate at least one byproduct
(Scheme 1).4
Table 1 Reaction of Dibenzoylmethane with Norbornenea
Ph
O
O
O
5 mol% catalyst
solvent
+
O
Ph
Ph
Ph
1a
2a
3a
Entry Catalyst
Solvent
Temp. (°C) Yield (%)b
1
2
AlCl3
TiCl4
MnCl2
BiCl3
InCl3
GaCl3
MeNO2
MeNO2
MeNO2
MeNO2
MeNO2
MeNO2
MeNO2
MeNO2
MeNO2
MeNO2
DCE
100
100
100
100
100
100
100
100
100
100
80
0
0
X
O
O
R4
, cat.
, cat.
R3
R1
R2
R4
XH
3
0
+
O
O
R3
O
4
trace
68
58
10
8
R1
R2
5
R4
O
R3
6
R1
R2
R4
7
CoCl2·6H2O
NiCl2·6H2O
CrCl3·6H2O
R3
8
Scheme 1
9
0
Consequently, the development of alternative methods,
such as using Lewis acids and Brønsted acids to catalyze
the addition of active methylene compounds to alkenes
and alkynes, would provide a more environmentally
friendly and atom-economical process. For examples,
Hartwig obtained good results in the palladium-catalyzed
addition of compounds with mildly acidic C–H bonds to
conjugated dienes.5 Li developed a highly effective inter-
molecular addition of active methylene compounds to alk-
enes using a mixture of AuCl3–AgOTf6 or AgOTf7 as
catalyst. Gold8 and nickel/ytterbium9 have also been ap-
plied to the intramolecular cyclization of d- and e-acety-
10
11
12
13
14
15
HAuCl4·4H2O
InCl3
20
32
trace
0
InCl3
CH2Cl2
dioxane
MeNO2
MeNO2
40
InCl3
80
InCl3
100
100
69c
78d
InCl3
a Reaction conditions: dibenzoylmethane (1.0 mmol), norbornene
(2.0 mmol), catalyst (5 mol%), solvent (2 mL), 12 h, argon.
b Isolated product yield after column chromatography.
c The reaction was conducted in open air.
d Reaction conditions: dibenzoylmethane (1.0 mmol), norbornene
(4.0 mmol), catalyst (5 mol%), solvent (2 mL), 12 h, in open air.
SYNLETT 2007, No. 20, pp 3219–3223
x
x
.x
x
.2
0
0
7
Advanced online publication: 03.12.2007
DOI: 10.1055/s-2007-992388; Art ID: W16907ST
© Georg Thieme Verlag Stuttgart · New York

3220
Y. Yuan, Z. Shi
LETTER
Our initial work focused on the screening of a variety of for the addition reaction of dibenzoylmethane to nor-
Lewis acids (5 mol%) as catalysts for the addition reaction bornene catalyzed by InCl3, whereas little or no product
of dibenzoylmethane (1a) to norbornene (2; 2.0 equiv). As was obtained with other solvent systems such as dichloro-
shown in Table 1, the best result for this reaction was ethane, dichloromethane or dioxane (entries 11–13). In
achieved using indium(III) chloride as the catalyst at 100 the case of the addition reaction of alkenes catalyzed by
°C in nitromethane for 12 hours (entry 5). The effect of FeCl3,12,14 the reaction was carried out in air without any
solvent on this addition reaction was tested subsequently. loss in yield (entry 14). Increasing the amount of nor-
Nitromethane was found to be the most suitable solvent
Table 2 Indium(III)-Catalyzed Reactions of Norbornene with 1,3-Diketonesa
O
O
O
O
5 mol% InCl3
R1
R2
+
R1
R2
MeNO2, 100 °C
1
2a
3
Entry
1
Diketone
Productb
Time (h)
36
Yield (%)c
94
O
O
O
O
O
Ph
Ph
Ph
Ph
R3
1a
3a
O
O
O
O
Ph
Ph
Ph
2
3
4
30
30
36
79 (50:50)
86 (50:50)
84 (48:52)
R3
MeO
OMe
OMe
1b
3b
O
O
O
O
O
MeO
Ph
R3
3c
1c
O
O
Ph
Ph
3d
Ph
3e
R3
Me
Cl
Me
1d
O
O
O
O
Ph
5
6
7
36
32
32
78 (50:50)
90 (24:76)
74 (48:52)
R3
Cl
1e
O
O
O
O
O
O
Ph
Me
Ph
Me
O
R3
1f
3f
O
Me
Me
R3
Me
Me
1g
3g
O
O
O
8
32
41
O
1h
3h
a The reactions were carried out using diketone (1.0 mmol), norbornene (4.0 mmol), and InCl3 (0.05 mmol) in anhyd MeNO2 (2 mL) in open air.
b R3 = norbornanyl.
c Isolated yield after column chromatography. The ratio of diastereomers is given in parentheses.
Synlett 2007, No. 20, 3219–3223 © Thieme Stuttgart · New York

LETTER
Indium(III)-Catalyzed Addition of 1,3-Dicarbonyl Compounds to Alkenes
3221
bornene used (4.0 equiv), improved the yield of the adduct tion of dibenzoylmethane to norbornene. GC–MS analy-
(entry 15).
sis of the crude reaction mixtures showed that this was due
to the formation of alkene dimers and oligomers in the
presence of the catalyst.12,16 Interestingly, the yield of the
addition product was found to be dependent on the solvent
used for the different alkenes. For examples, nitromethane
was the best solvent for the addition of styrene-type alk-
enes as less oligomer was formed (entries 1 and 2). On the
other hand, addition reaction of dienes and dihydropyran
was most efficient when conducted in CH2Cl2 (entries 3–
5).
To examine the substrate scope of the addition reaction,
various 1,3-dicarbonyl compounds were reacted with nor-
bornene under the optimized conditions. In the presence
of 5 mol% of InCl3, all substituted dibenzoylmethane and
1-benzoylacetone compounds reacted well with nor-
bornene to give the corresponding addition products in
good yields in acceptable times (Table 2). However, only
moderate yields were observed when acetylacetone (not
shown in Table 2) or 1,3-cyclohexadione were used as the
substrate under the same reaction conditions. It was deter- It has previously been shown in the literature that phenols,
mined that the phenyl group in the active methylene com- carboxylic acids, amines and aryl compounds add to alk-
pounds was very important for the reaction to proceed in enes in the presence of several Lewis and Brønsted acid
good yield. This could be due to the 1,3-allylic strain in catalysts.17 Therefore our attention next turned to the
the enol form that could increase the substrate’s reactivi- scope of nucleophiles that could be applied to the addition
ty.9,15
reaction to alkenes. Hence, reaction of 4-methylbenzoic
acid with norbornene in the presence of 5 mol% of InCl3
gave 2-(4-methyl)benzoyloxynorbornane in 97% yield
when nitromethane was used as solvent. The reactions us-
ing 4-chlorophenol and tosylamine were found to be
equally effective. Hence, InCl3 was shown to be a general
catalyst for the addition reaction of nucleophiles to alk-
enes in good yields (Scheme 2).
Next, we investigated the scope of alkene substrates com-
patible with the InCl3-catalyzed addition reaction of
dibenzoylmethane (1a, Table 3). The catalyst loading of
InCl3 was increased to 10 mol% because only poor yields
(less than 20%) of the addition of 1a to dienes were ob-
tained with 5 mol% of catalysts. Here, the yields obtained
were only moderate in comparison with the addition reac-
Table 3 Indium(III)-Catalyzed Reactions of Alkenes with Dibenzoylmethanea
O
O
O
O
R2
10 mol% InCl3
Ph
Ph
R2
R1
+
Ph
Ph
R1
1a
2
3
Entry
1
Alkene
Productb
Solvent
MeNO2
Temp. (°C)
100
Time (h)
15
Yield (%)c
65
R3
2b
3i
R3
2
3
MeNO2
CH2Cl2
100
40
15
20
73
48
Cl
Cl
3j
O
2c
R3
R3
R3
O
2d
3k
4
5
CH2Cl2
CH2Cl2
40
40
20
20
58
40
2e
2f
3l
3m
a Unless otherwise noted, the reactions were carried out using b-diketone (1.0 mmol), alkene (4.0 mmol), and InCl3 (0.1mmol) in anhyd solvent
(2 mL), in open air.
b R3 = dibenzoylmethyl.
c Isolated yield after column chromatography.
Synlett 2007, No. 20, 3219–3223 © Thieme Stuttgart · New York

3222
Y. Yuan, Z. Shi
LETTER
Ts
NH
4
77%
TsNH2
MeNO2
100 °C
Ph
O
O
O
Cl
HO
Cl
Ph
Ph
O
+
O
MeNO2,100 °C
cyclohexane, 80 °C
InCl3 (cat.)
Ph
3a
5
94%
60%
COOH
MeNO2
100 °C
O
O
6
97%
Scheme 2
Lett. 2007, 9, 825. (g) Li, Z.; Li, C. J. Am. Chem. Soc. 2006,
128, 56. (h) Sanz, R.; Miguel, D.; Martinez, A.; Alvarez-
Gutierrez, J. M.; Rodriguez, F. Org. Lett. 2007, 9, 727.
(i) Sanz, R.; Miguel, D.; Martinez, A.; Alvarez-Gutierrez, J.
M.; Rodriguez, F. Org. Lett. 2007, 9, 2027.
In summary, we have developed a new InCl3-catalyzed
addition reaction of 1,3-dicarbonyl compounds to various
alkenes.18 The reaction proceeded in good yields and can
be carried out in air. It provides an easy and practical pro-
cedure for carbon–carbon bond formation because of the
readily availability of the catalyst and simple reaction
conditions. Furthermore, the reaction can also be applied
to carbon–heteroatom bond formation using alternative
nucleophiles. Mechanistic studies on this reaction are in
progress.
(3) (a) Anastas, P. T.; Warner, J. C. Green Chemistry: Theory
and Practice; Oxford University Press: Oxford, 1998.
(b) Ahluwalia, V. K.; Kidwai, M. New Trends in Green
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(c) Kidwai, M. Pure Appl. Chem. 2006, 78, 1983.
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Acc. Chem. Res. 2002, 35, 695.
(5) Leitner, A.; Larsen, J.; Steffens, C. J.; Hartwig, F. J. Org.
Chem. 2004, 69, 7552.
Acknowledgment
(6) (a) Yao, X.; Li, C. J. Am. Chem. Soc. 2004, 126, 6884.
(b) Nguyen, R.; Yao, X. D.; Bohle, S.; Li, C. Org. Lett. 2005,
7, 673.
(7) Yao, X.; Li, C. J. Org. Chem. 2005, 70, 5752.
(8) (a) Kennedy-Smith, J. J.; Staben, S. T.; Toste, F. D. J. Am.
Chem. Soc. 2004, 126, 4526. (b) Staben, S. T.; Kennedy-
Smith, J. J.; Toste, F. D. Angew. Chem. Int. Ed. 2004, 43,
5350.
We are grateful for the financial support from the National Natural
Science Foundation of China (20702043), Jiangsu Provincial Natu-
ral Science Foundation (BK2006549) P. R. of China, and Program
for New Century Excellent Talents in Yangzhou University.
References and Notes
(9) Gao, Q.; Zheng, B.-F.; Li, J.-H.; Yang, D. Org. Lett. 2005,
7, 2185.
(10) Kuninobu, Y.; Kawata, A.; Takai, K. Org. Lett. 2005, 7,
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(11) Endo, K.; Hatakeyama, T.; Nakamura, M.; Nakamura, E.
J. Am. Chem. Soc. 2007, 129, 5264.
(12) (a) Kischel, J.; Michalik, D.; Zapf, A.; Beller, M. Chem.
Asian J. 2007, 2, 909. (b) Duan, Z.; Xuan, X.; Wu, Y.
Tetrahedron Lett. 2007, 48, 5157.
(1) (a) March, J. Advanced Organic Chemistry, 4th ed.; Wiley:
New York, 1992. (b) Scolastic, C.; Nocotra, F. Current
Trends in Organic Synthesis; Plenum: New York, 1999.
(2) (a) Yasuda, M.; Somyo, T.; Baba, A. Angew. Chem. Int. Ed.
2006, 45, 793. (b) Qin, H.; Yamagiwa, N.; Matsunaga, S.;
Shibasaki, M. Angew. Chem. Int. Ed. 2007, 46, 409.
(c) Kischel, J.; Mertins, K.; Michalik, D.; Zapf, A.; Beller,
M. Adv. Synth. Catal. 2007, 349, 865. (d) Jana, U.; Biswas,
S.; Maiti, S. Tetrahedron Lett. 2007, 48, 4065. (e) Zhang,
Q.; Sun, S.; Hu, J.; Liu, Q.; Tan, J. J. Org. Chem. 2007, 72,
139. (f) Rueping, M.; Nachtsheim, B. J.; Kuenkel, A. Org.
(13) Motokura, K.; Fujita, N.; Mori, K.; Mizugaki, T.; Ebitani,
K.; Kaneda, K. Angew. Chem. Int. Ed. 2006, 45, 2605.
Synlett 2007, No. 20, 3219–3223 © Thieme Stuttgart · New York

LETTER
Indium(III)-Catalyzed Addition of 1,3-Dicarbonyl Compounds to Alkenes
3223
(14) Kischel, J.; Jovel, I.; Mertins, K.; Zapf, A.; Beller, M. Org.
Lett. 2006, 8, 19.
(15) (a) Iglesias, E. J. Phys. Chem. 1996, 100, 12592.
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43, 3777.
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(17) For some samples, see references 12, 13, 15, and:
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2005, 5103. (b) Reuping, M.; Nachtsheim, B. J.; Scheidt, T.
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2 H), 2.33 (s, 3 H), 2.18 (s, 3 H), 2.16 (s, 2 H), 1.87 (s, 2 H),
1.53–1.56 (m, 2 H), 1.40 (m, 6 H), 1.19–1.22 (m, 2 H), 1.11–
1.14 (m, 4 H), 1.03 (m, 2 H). 13C NMR [150 MHz, CDCl3;
diastereomeric mixture (48:52)]: d = 196.06, 195.49, 195.46,
194.88, 144.57, 144.32, 137.27, 137.18, 134.77, 134.65,
133.48, 133.28, 129.66, 129.49, 129.15, 129.01, 128.95,
128.89, 128.78, 128.74, 64.39, 64.33, 43.70, 43.65, 39.78,
39.55, 37.45, 37.12, 36.76, 36.07, 30.11, 30.10, 28.60,
28.58, 21.73, 21.67. Anal. Calcd for C23H24O2: C, 83.10; H,
7.28. Found: C, 82.84; H, 7.42. Product 3e: 1H NMR [600
MHz, CDCl3; diastereomeric mixture (50:50)]: d = 7.88–
8.04 (m, 8 H), 7.35–7.60 (m, 10 H), 4.93 (d, J = 11.4 Hz, 2
H), 2.69–2.72 (m, 2 H), 2.25 (s, 2 H), 1.94 (s, 1 H), 1.91 (s,
1 H), 1.60–1.62 (m, 2 H), 1.47 (m, 6 H), 1.27–1.29 (m, 2 H),
1.21–1.98 (m, 2 H), 1.06–1.10 (m, 2 H). 13C NMR [150
MHz, CDCl3; diastereomeric mixture (50:50)]: d = 195.84,
195.22, 194.77, 194.20, 140.17, 139.94, 137.11, 136.99,
135.44, 135.35, 133.75, 133.54, 130.40, 130.24, 129.27,
129.11, 129.02, 128.97, 128.86, 128.82, 64.95, 64.93, 43.60,
39.72, 39.67, 37.29, 37.22, 36.76, 36.05, 36.04, 30.09,
28.55. Anal. Calcd for C22H21ClO2: C, 74.89; H, 6.00.
Found: C, 74.50; H, 6.06. Product 3g: 1H NMR [600 MHz,
CDCl3; diastereomeric mixture (48:52)]: d = 7.90–7.93 (m,
4 H), 7.26–7.29 (m, 4 H), 4.26 (d, J = 11.4 Hz, 1 H), 4.20 (d,
J = 11.4 Hz, 1 H), 2.50–2.57 (m, 2 H), 2.42 (s, 3 H), 2.41 (s,
3 H), 2.27 (s, 1 H), 2.19 (s, 1 H), 2.13 (s, 3 H), 2.10 (s, 3 H),
1.94 (s, 1 H), 1.81 (s, 1 H), 1.09–1.52 (m, 15 H), 0.86–0.88
(m, 1 H). 13C NMR [150 MHz, CDCl3; diastereomeric
mixture (48:52)]: d = 204.65, 204.43, 196.00, 196.54,
144.82, 144.79, 134.93, 134.87, 129.62, 129.57, 70.66,
70.11, 42.53, 42.43, 40.19, 39.03, 37.25, 36.88, 36.72,
35.79, 35.72, 35.33, 30.11, 30.08, 28.60, 28.58, 27.33,
27.12, 21.75. HRMS: m/z calcd for C18H22O2: 270.1620;
found: 270.1620. Product 3h: 1H NMR (600 MHz, CDCl3):
d = 5.30 (s, 1 H), 4.02 (d, J = 6.6 Hz, 1 H), 2.40–2.41 (m, 1
H), 2.30–2.36 (m, 5 H), 1.05–1.98 (m, 10 H). 13C NMR (150
MHz, CDCl3): d = 199.91, 176.84, 103.79, 81.35, 40.98,
39.81, 36.76, 35.38, 35.34, 29.36, 28.21, 24.21, 21.31.
HRMS: m/z calcd for C13H18O2: 206.1307; found: 206.1307.
Product 6: 1H NMR (600 MHz, CDCl3): d = 7.90 (d, J = 7.8
Hz, 2 H), 7.22 (d, J = 7.8 Hz, 2 H), 4.83 (d, J = 6.6 Hz, 1 H),
2.44 (d, J = 4.8 Hz, 1 H), 2.40 (s, 3 H), 2.33 (br s, 1 H), 1.82
(ddd, J = 2.4, 7.2, 13.8 Hz, 1 H), 1.45–1.65 (m, 4 H), 1.15–
1.23 (m, 3 H). 13C NMR (150 MHz, CDCl3): d = 166.36,
143.35, 129.56, 129.03, 128.21, 77.98, 41.63, 39.74, 35.50,
28.28, 24.37, 21.70. HRMS: m/z calcd for C15H18O2:
230.1307; found: 230.1307.
(18) All the products have been fully characterized by 1H NMR
(600 MHz) and 13C NMR (150 MHz) and the analyses were
in agreement with published data. Data that were not found
in the literature are as follows: Product 3b: 1H NMR [600
MHz, CDCl3; diastereomeric mixture (50:50)]: d = 8.03–
8.05 (m, 4 H), 7.93–7.96 (m, 4 H), 7.36–7.56 (m, 6 H), 6.85–
6.94 (m, 4 H), 4.95 (d, J = 3.6 Hz, 1 H), 4.93 (d, J = 3.0 Hz,
1 H), 3.85 (s, 3 H), 3.81 (s, 3 H), 2.67–2.73 (m, 2 H), 2.24 (s,
2 H), 1.94 (s, 2 H), 1.55–1.64 (m, 2 H), 1.40–1.47 (m, 6 H),
1.25–1.30 (m, 2 H), 1.17–1.20 (m, 4 H), 1.07–1.12 (m, 2 H).
13C NMR [150 MHz, CDCl3; diastereomeric mixture
(50:50)]: d = 196.22, 196.63, 194.31, 193.68, 163.89,
163.72, 137.27, 137.18, 133.44, 133.25, 131.42, 131.28,
130.26, 130.12, 128.94, 128.81, 128.77, 128.72, 114.12,
113.95, 64.57, 64.49, 55.57, 55.52, 43.62, 43.59, 39.84,
39.52, 37.48, 37.00, 36.77, 36.76, 36.05, 36.03, 30.10,
28.60, 28.58. HRMS: m/z calcd for C23H24O3: 348.1725;
found: 348.1720. Product 3c: 1H NMR [600 MHz, CDCl3;
diastereomeric mixture (50:50)]: d = 7.93–8.04 (m, 4 H),
7.28–7.65 (m, 12 H), 7.04–7.12 (m, 2 H), 5.02 (d, J = 11.4
Hz, 2 H), 3.81 (s, 3 H), 3.73 (s, 3 H), 2.68–2.72 (m, 2 H),
2.24 (s, 2 H), 1.95 (s, 2 H), 1.61–1.65 (m, 2 H), 1.48 (m, 6
H), 1.29 (m, 2 H), 1.20–1.21 (m, 4 H), 1.09–1.11 (m, 2 H).
13C NMR [150 MHz, CDCl3; diastereomeric mixture
(50:50)]: d = 195.92, 195.69, 195.27, 195.00, 160.08,
159.94, 138.61, 138.55, 137.33, 137.25, 133.55, 133.35,
129.89, 129.74, 128.97, 128.82, 121.52, 121.40, 120.42,
120.31, 112.95, 112.73, 64.33, 55.47, 55.39, 43.81, 43.79,
39.74, 39.65, 37.39, 37.28, 36.78, 36.13, 30.13, 28.61.
HRMS: m/z calcd for C23H24O3: 348.1725; found: 348.1720.
Product 3d: 1H NMR [600 MHz, CDCl3; diastereomeric
mixture (48:52)]: d = 7.77–7.96 (m, 8 H), 7.29–7.48 (m, 6
H), 7.10–7.19 (m, 4 H), 4.91 (d, J = 10.8 Hz, 2 H), 2.64 (m,
Synlett 2007, No. 20, 3219–3223 © Thieme Stuttgart · New York

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