PdII-catalyzed oxidative dimeric cyclization-coupling reaction of 2,3-allenoic acids: an efficient synthesis of bibutenolide derivatives

Article abstract of DOI:10.1002/chem.200401079

Three sets of convenient catalytic systems have been developed for the oxidalive dimeric cyclization coupling of differently substituted 2,3-allenoic acids catalyzed by Pd^II, affording bibutenolides that are not otherwise readily available. The advantages and disadvantages of these systems are discussed. Although the diastereoselectivity for the bicyclization of racemic 2,3-allenoic acids is low, excellent diastereoselectivity was realized in the bicyclization reaction of optically active 23-allenoic acids, leading to the optically active bibutenolides in high yields and ee. Based on a mechanistic study, it is believed that the reaction may proceed by means of a double oxypalladation and reductive elimination to yield butenolide 3 and Pd° species, which may be reoxidized to the catalytically active Pd^II species in the presence of alkyl iodide/air, metallic iodide/air, or benzoquinone.

Full text of DOI:10.1002/chem.200401079

FULL PAPER
II
Pd -Catalyzed Oxidative Dimeric Cyclization–Coupling Reaction of 2,3-
Allenoic Acids: An Efficient Synthesis of Bibutenolide Derivatives
[
a]
Shengming Ma,* Zhanqian Yu, and Zhenhua Gu
Abstract: Three sets of convenient cat-
alytic systems have been developed for
the oxidative dimeric cyclization cou-
pling of differently substituted 2,3-alle-
allenoic acids is low, excellent diaster-
eoselectivity was realized in the bicycli-
zation reaction of optically active 2,3-
allenoic acids, leading to the optically
active bibutenolides in high yields and
ee. Based on a mechanistic study, it is
believed that the reaction may proceed
by means of a double oxypalladation
and reductive elimination to yield bute-
0
nolide 3 and Pd species, which may be
II
noic acids catalyzed by Pd , affording
reoxidized to the catalytically active
II
bibutenolides that are not otherwise
readily available. The advantages and
disadvantages of these systems are dis-
cussed. Although the diastereoselectivi-
ty for the bicyclization of racemic 2,3-
Pd species in the presence of alkyl
iodide/air, metallic iodide/air, or benzo-
quinone.
Keywords: allenes · butenolides ·
homogeneous catalysis · palladium
Introduction
Allenes are three-carbon functional groups that possess two
perpendicular p orbitals with great potential in organic syn-
thesis in terms of chirality transfer and diversity, due to the
existence of the axial chirality and the substituent-loading
Scheme 1. FG=functional group.
[1,2]
capability.
Under the catalysis of the palladium species,
functionalized allene compounds have also been reported to
[3–8]
[12]
form a variety of cyclic compounds.
Recently, we estab-
activities and a structural unit in many natural products.
lished a new area of transition-metal-catalyzed oxidative
cyclization–dimerization reactions between two different
functionalized allenes to give interesting bicyclic compounds
In this paper, we wish to present new and efficient catalytic
systems; the scope and mechanism of this reaction in detail.
[9]
in a single step (Scheme 1).
In this reaction, the regeneration of catalytically active
Results and Discussion
II
[10]
[11]
Pd is critical. In a preliminary communication, we dis-
closed an oxidative cyclization–coupling reaction of 2,3-alle-
We have developed three systems to realize this reaction.
The results are listed in Table 1. When five equivalents of
propyl iodide (2a) were added in DMA, the oxidative cycli-
noic acids catalyzed by PdCl by applying excess of an alkyl
2
iodide as the oxidant for the synthesis of bibutenolides,
which is of current interest due to their potential biological
zation–coupling reaction catalyzed by PdCl led to the for-
2
mation of 3a in 74% yield (Table 1, entry 1). The yield de-
creased when a smaller amount of 2a was added (Table 1,
entry 2). Furthermore the yields were also lower in other
solvents (Table 1, entries 3–5). An explanation of this reac-
[
a] Prof. S. Ma, Z. Yu, Z. Gu
State Key Laboratory of Organometallic Chemistry
Shanghai Institute of Organic Chemistry
Chinese Academy of Sciences, 354 Fenglin Lu
Shanghai 200032 (P. R. China)
0
tion is the possible oxidation of the in-situ formed Pd to
II
Pd with I , which may be formed by the aerobic oxidation
2
À
of I released from alkyl iodide. Thus, alkyl iodide was re-
Fax : (+86)21-641-67510
placed with metallic iodide. It is interesting to observe that
the reaction also proceeded smoothly to yield 3a (Table 1,
entries 6–9). Furthermore, the reaction can also occur with
E-mail: masm@mail.sioc.ac.cn
Supporting information for this article is available on the WWW
under http://www.chemeurj.org/ or from the author.
Chem. Eur. J. 2005, 11, 2351 – 2356
DOI: 10.1002/chem.200401079
ꢀ 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2351

II
Table 1. Pd -catalyzed oxidative cyclization–coupling reaction of 4-
When we used two alkyl iodides with high boiling points,
that is, 2b and 2c, after the reaction they were recovered in
[
a]
phenyl-2-propyl-2,3-butadienoic acid (1a).
9
4 and 95% yields, respectively, indicating that most of the
alkyl iodide was not consumed during the reaction [Eqs. (2)
and (3)]. After analyzing the crude reaction mixture, no
product derived from the alkyl iodide was detected.
Entry
Additive
equiv)
Solvent
T
[8C]
t
Yield of 3a
[b]
(
[h]
[%]
74
62
trace
66
42
62
68
74
1
2
3
4
5
6
7
8
9
C
C
C
C
C
3
3
3
3
3
H
H
H
H
H
7
I (5)
7
I (3)
7
I (5)
7
I (5)
7
I (5)
DMA
DMA
THF
MeCN
EtOH
DMA
DMA
DMA
DMA
DMF
80
80
reflux
reflux
reflux
80
80
80
80
80
10
6.5
46
16
10
5
TBAI (1)
NaI (0.5)
KI (0.5)
KI (0.2)
5
5
5
2
64
92
[
c]
1
0
BQ (0.63)
[
[
a] The reaction was carried out using 0.25 mmol of 2,3-allenoic acids.
b] Isolated yield. [c] BQ=benzoquinone.
20 mol% KI. The best result was obtained when 50 mol%
KI was used, leading to a 74% yield of product 3a (Table 1,
In all the cases reported in Table 2, the distereoselectivity
of the products is low, ranging from 1.0 to 2.18. However,
with optically active 4-aryl-2,3-allenoic acids, which could be
easily obtained by resolution of the racemic allenoic acids,
only one diastereoisomer of 3 was obtained. Some typical
results are listed in Table 3. In the presence of benzoqui-
none, the reaction gave the corresponding compounds in ex-
cellent yields, diastereoselectivity, and ee. The absolute con-
figurations of two chiral centers in the product (+)-3o from
the S-configuration allenoic acid (S)-(+)-1o were deter-
entry 8). In addition, benzoquinone was reported to be a
0
II
good oxidant for the transformation of Pd to Pd under
[13]
acidic conditions. Thus, 0.63 equivalents of benzoquinone
slightly more than the required 0.5 equiv) was applied as
(
the oxidant to afford 3a in a much higher yield (92%;
Table 1, entry 10).
Some typical results are summarized in Table 2. It should
be noted that a variety of alkyl- and aryl-substituted 2,3-alle-
noic acids successfully underwent cyclization–coupling reac-
tions to afford bibutenolides in decent yields. The RI/O2
system (method A) is the most general, although the yield
[15]
mined to be S,S by the X-ray diffraction study (Figure 1),
II
indicating that the cyclization was realized by a Pd -cata-
1
2
[2e–g]
may not be the highest; with R being alkyl and R being
benzyl, alkyl, or hydrogen, the reaction did not give the cor-
responding product in good yields when KI (method B) was
used as the additive (Table 2, entries 16, 19, 23, 27, 31, 35,
and 39). Benzoquinone (methods C and D) is more suitable
for the reaction of 4-aryl-2-alkyl/benzyl-substituted and 4-
alkyl-substituted-2-nonsubstituted allenoic acids, affording
bibutenolides 3a–e,j–l in higher yields (Table 2, entries 3, 6,
lyzed oxypalladation process.
9, 11, 14, 32, 33, 36, 37, 40, and 41).
Mechanistic study: At first, the reaction with 5 mol% PdCl2
under an argon atmosphere occurred with difficulty to
afford 3a only in 26% yield, along with 4a in a 12% yield
[Eq. (1)], which indicates that the oxygen in air may partici-
pate in the catalytic cycle.
Figure 1. ORTEP representation of the product (S,S)-(+)-3o.
2352
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Chem. Eur. J. 2005, 11, 2351 – 2356

Homogeneous Catalysis
FULL PAPER
Table 2. Oxidative dimeric cyclizing-coupling reaction of 2,3-allenoic acids.
Based upon these experi-
mental findings, it was pro-
posed that the Pd species
II
firstly coordinates with the rel-
atively
electron-rich
CÀC
double bond in the allene
moiety to form a coordination
[
a]
Entry
Substrate 1
Method
t
Yield
[%] of 3
R*S*/R*R*
1
2
R
R
[h]
II
complex. Subsequently, Pd -in-
1
2
3
Ph
Ph
Ph
n-C
3
H
7
(1a)
method A
method B
method C
10
5
74 (3a)
75 (3a)
92 (3a)
1/1.87
1/2.18
1/1.65
duced double cyclic oxypalla-
dation, which is responsible for
the high efficiency of chirality
transfer observed with the
optically active 2,3-allenoic
2
4
5
6
CH
3
(1b)
method A
method B
method C
4
4
2
64 (3b)
74 (3b)
96 (3b)
1/1.62
1/1.66
1/2.03
[2e–g]
acids,
would afford inter-
7
8
9
PhCH
2
(1c)
method A
method B
method C
11.5
11.5
2
75 (3c)
mixture
94 (3c)
1/1.53
–
0.9/1
mediate 5o. Subsequent reduc-
tive elimination yields the bib-
0
utenolide (S,S)-3o and the Pd
0
species. Then the Pd species is
1
1
0
1
a-naphthyl
a-naphthyl
CH
3
(1d)
method A
method C
4
2
71 (3d)
92 (3d)
1/1.28
1/1.84
reoxidized by the in-situ-
formed I , which may be pro-
2
12
13
14
n-C
3
H
7
(1e)
method A
method B
method C
4.5
6
2
64 (3e)
65 (3e)
67 (3e)
1/1.43
1/1.54
1/1.33
duced by the reaction of alkyl
iodide or KI with the oxygen
in air, or benzoquinone to give
II
15
16
17
CH
3
PhCH
2
(1 f)
method A
method B
method C
3.5
5
2
72 (3 f)
15 (3 f)
36 (3 f)
1.04/1
–
–
the catalytically active Pd spe-
cies to complete the catalytic
cycle (Scheme 2).
1
1
2
2
8
9
0
1
n-C
6
H
13
CH
CH
3
(1g)
(1h)
method A
method B
method C
method D
21
17
3.5
2
47 (3g)
11 (3g)
13 (3g)
1/1.87
1.23/1
1/1.84
–
Conclusion
[
b]
We have developed an oxida-
tive dimeric cyclization–cou-
pling reaction of 2,3-allenoic
acids catalyzed by PdCl , af-
fording bi-butenolides
22
23
24
25
CH
3
3
method A
method B
method C
method D
20
22.5
2
43 (3h)
mixture
22 (3h)
20 (3h)
1/1.13
–
1/2
11
1/1.62
2
[16]
that
26
27
28
29
n-C
n-C
n-C
n-C
3
5
7
8
H
H
H
H
7
n-C
3
H
7
(1i)
method A
method B
method C
method D
17
2.5
2
61 (3i)
25 (3i)
1/1.59
1/1.02
–
–
are not otherwise readily avail-
able, by using three oxidative
systems. Although the diaster-
eoselectivity for the bicycliza-
tion of racemic 2,3-allenoic
acids is low, excellent diaster-
eoselectivity was realized in
the bicyclization reaction of
optically active 2,3-allenoic
acids, leading to the optically
active bibutenolides in high
yields and ee. Further studies
on the application of these
[
c]
2.5
mixture
30
31
32
33
11
15
17
H (1j)
H (1k)
H (1l)
method A
method B
method C
method D
3
15
2
52 (3j)
mixture
46 (3j)
61 (3j)
1/1.67
–
1/1.06
1.19/1
2
34
35
36
37
method A
method B
method C
method D
6
21
2
49 (3k)
mixture
80 (3k)
83 (3k)
1/1
–
1.06/1
1/1.05
[
d]
2
[
e]
38
39
40
41
method A
method B
method C
method D
3
2
2
2
54 (3l)
32 (3l)
71 (3l)
73 (3l)
1/1
1/1.38
1/1.06
1/1.06
II
Pd -regenerating oxidation sys-
tems are being pursued in our
laboratory.
4
4
2
3
H
H
Bn (1m)
H (1n)
method A
method C
10.5
2
mixture
–
–
NR
Experimental Section
[
a] See the Experimental Section for the general procedures for methods A–D. [b] 62% of cycloismerization
product was isolated. [c] 8% of cycloismerization product was isolated. [d] Carried out in 0.25 mmol scale of
2
eochemistry of 3j and 3k were established by the comparison with 3l.
[
14]
,3-allenoic acid. [e] The stereochemistry of 3l was determined by the X-ray diffraction study, and the ster-
General procedures Method A: A so-
lution of 2,3-allenoic acid (1;
Chem. Eur. J. 2005, 11, 2351 – 2356
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S. Ma et al.
Table 3. Oxidative dimeric cyclizing-coupling reaction of optical active 2,3-allenoic acids.
Method B: A solution of 2,3-allenoic
acid (1; 0.50 mmol), KI (42 mg,
0
.25 mmol),
and
PdCl
2
(4 mg,
0
.023 mmol) in DMA (2 mL) was stir-
red in air at 808C for the time indi-
cated in Table 2 to afford 3.
Method C: A solution of 2,3-allenoic
acid (1; 0.50 mmol), benzoquinone
[
a]
Entry Allenoic acids
Equiv of BQ Product 3
Yield
of 3 [%] 3 [%]
ee of R*R*/R*S*
(
0.30 mmol), and PdCl
2
(4 mg,
0
.023 mmol) in DMF (2 mL) was stir-
red at 808C for the time indicated in
Table 2 to afford 3.
1
0.63
88
100
86
>99 >99:1
Method D: A solution of 2,3-allenoic
acid (1; 0.50 mmol), benzoquinone
(
0.30 mmol), and PdCl
2
(4 mg,
0
.023 mmol) in DMA (2 mL) was stir-
red at 808C for the time indicated in
Table 2 to afford 3.
2
3
0.58
0.74
99
25:1
20:1
For the analytical data of 3a–f see
the Supporting Information of refer-
ence [11].
3
,3’-Dimethyl-5,5’-dihexyl-5H,5’H-
[
4,4’]bifuranyl-2,2’-dione (3g)
>99
Method A: A solution of 2-methyl-
deca-2,3-dienoic acid (1g; 92 mg,
0
.51 mmol), 2a (428 mg, 2.50 mmol),
and PdCl (5 mg, 0.028 mmol) in
2
DMA (5 mL) was stirred at 808C for
21 h to afford 43 mg (47%) of 3g
4
0.67
94
98
24:1
(
R*,S*:R*,R*=1:1.87).
Method B: A solution of 1g (91 mg,
.50 mmol), KI (42 mg, 0.25 mmol),
and PdCl (4 mg, 0.023 mmol) in
DMA (3 mL) was stirred at 808C for
7 h to afford 10 mg (11%) of 3g (R*,S*:R*,R*=1.23:1).
Method C: A solution of 1g; 92 mg, 0.51 mmol), benzoquinone (32 mg,
0
1
[
a] The ratio was determined by the H NMR spectra.
2
1
0
2
.30 mmol), and PdCl (4 mg, 0.023 mmol) in DMF (2 mL) was stirred at
8
08C for 3.5 h to afford 12 mg (13%) of 3g (R*,S*:R*,R*=1:1.84).
1
R*,R* isomer (less polar): liquid; H NMR (300 MHz, CDCl
3
): d=5.04
(
br, 2H), 1.92 (s, 6H), 1.48–1.15 (m, 20H), 0.88 ppm (t, J=6.6 Hz, 6H);
1
3
C NMR (75.4 MHz, CDCl
1.1, 129.0, 151.1, 172.5 ppm; EIMS: m/z (%): 362 (3.79) [M ], 69 (100);
3
): d=10.7, 14.0, 22.4, 24.6, 28.8, 31.5, 33.1,
+
8
À1
+
IR (neat): n˜ =2928, 2858, 1755 cm ; HRMS: m/z calcd for C22
35 4
H O
+
[
M +1]: 363.25299; found: 363.2552.
1
R*,S* isomer (more polar): liquid; H NMR (300 MHz, CDCl
3
): d=5.00–
5
.90 (m, 2H), 1.82 (d, J=2.1 Hz, 6H), 1.70–1.15 (m, 20H), 0.89 ppm (t,
1
3
J=6.6 Hz, 6H); C NMR (75.4 MHz, CDCl
3
): d=10.0, 14.0, 22.4, 25.3,
2
8.8, 31.5, 33.3, 81.9, 129.4, 152.0, 172.2 ppm; EIMS: m/z (%): 362 (4.53)
+
À1
[
M ], 43 (100); IR (neat): n˜ =2956, 2928, 2858, 1757 cm ; HRMS: m/z
+ +
calcd for C22
H
35
O
4
[M +1]: 363.25299; found: 363.2548.
3
,3’-Dimethyl-5,5’-dimethyl-5H,5’H-[4,4’]bifuranyl-2,2’-dione (3h)
Method A: A solution of 2-methylpenta-2,3-dienoic acid (1h; 56 mg,
.50 mmol), 2a (420 mg, 2.47 mmol), and PdCl (4 mg, 0.023 mmol) in
DMA (2 mL) was stirred at 808C for 20 h to afford 24 mg (43%) of 3h
d.r.=1:1.13).
Method C: A solution of 1h (56 mg, 0.50 mmol), benzoquinone (32 mg,
0
2
(
Scheme 2.
0
8
.30 mmol), and PdCl
08C for 2 h to afford 12 mg (22%) of 3h (d.r.=1:2).
2
(4 mg, 0.023 mmol) in DMF (2 mL) was stirred at
Method D: A solution of 1h (56 mg, 0.50 mmol), benzoquinone (32 mg,
.30 mmol), and PdCl (4 mg, 0.023 mmol) in DMA (2 mL) was stirred at
808C for 11 h to afford 11 mg (20%) of 3h (d.r.=1:1.62).
0
2
0
0
.50 mmol), propyl iodide (2a; 2.50 mmol), and PdCl
.023 mmol) in DMA (2 mL) was stirred in air at 808C for the time indi-
2
(4 mg,
1
Solid, m.p. 153–1758C (ethyl acetate and petroleum ether); H NMR
cated in the tables. Then the mixture was diluted with diethyl ether,
washed with water, and dried by MgSO . After evaporation, the residues
were purified by flash chromatography on silica gel with petroleum
(300 MHz, CDCl ): d=5.25–5.03 (2m, 2H), 1.94, 1.84 (2d, J=2.1 Hz,
3
4
6H), 1.47, 1.39 ppm (2d, J=6.9 Hz, 6H); EIMS: m/z (%): 222 (16.86)
+
À1
[M ], 151 (100); IR (KBr): n˜ =2927, 1759 cm ; elemental analysis calcd
(%) for C12 : C 64.85, H 6.35; found: C 64.54, H 6.29.
ether/ethyl acetate as the eluent to afford 3.
14 4
H O
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Homogeneous Catalysis
FULL PAPER
3
,3’-Dipropyl-5,5’-dipropyl-5H,5’H-[4,4’]bifuranyl-2,2’-dione (3i)
Method A: A solution of 2-propylhepta-2,3-dienoic acid (1i; 84 mg,
.50 mmol), 2a (425 mg, 2.50 mmol), and PdCl (4 mg, 0.023 mmol) in
DMA (2 mL) was stirred at 808C for 17 h to afford 51 mg (61%) of 3i
d.r.=1:1.59).
Method B: A solution of 1i (85 mg, 0.51 mmol), KI (42 mg, 0.25 mmol),
and PdCl (4 mg, 0.023 mmol) in DMA (2 mL) was stirred at 808C for
.5 h to afford 21 mg (25%) of 3i (d.r.=1:1.02).
R*,R* isomer (less polar): solid, m.p. 146–1478C (ethyl acetate);
1
H NMR (300 MHz, CDCl
3
): d=6.26 (d, J=1.2 Hz, 2H), 5.26 (dd, J=
1
2
.2, 6.3 Hz, 2H), 2.15–1.98 (m, 2H), 1.74–1.54 (m, 2H), 1.50–1.12 (m,
0
2
1
3
0H), 0.88 ppm (t, J=6.0 Hz, 6H); C NMR (75.4 MHz, CDCl
3
): d
=
14.0, 22.5, 24.2, 29.0, 29.1, 31.6, 33.9, 82.7, 121.2, 155.5, 170.8 ppm;
(
+
EIMS: m/z (%): 362 (9.16) [M ], 57 (100); IR (KBr): n˜ =2956, 2927,
À1
+
+
2
856, 1732 cm ; HRMS: m/z calcd for C22
found: 363.2557.
R*,S* isomer (more polar): solid, m.p. 63–648C (diethyl ether and petro-
H
35
O
4
[M +1]: 363.25299;
2
2
1
3
Solid, m.p. 123–1258C (ethyl acetate); H NMR (300 MHz, CDCl ): d=
5
0
1
leum ether); H NMR (300 MHz, CDCl
3
): d=6.21 (d, J=1.2 Hz, 2H),
.05–4.83 (2m, 2H), 2.40–2.01 (2m, 4H), 1.80–1.30 (m, 12H), 1.05–
5
.30 (bd, J=6.0 Hz, 2H), 2.09–1.92 (m, 2H), 1.86–1.50 (m, 2H), 1.50–1.18
+
.82 ppm (m, 12H); EIMS: m/z (%): 334 (12.06) [M ], 291 (100); IR
1
3
(
m, 20H), 0.88 ppm (t, J=6.6 Hz, 6H); C NMR (75.4 MHz, CDCl
3
): d
À1
(
KBr): n˜ =2961, 2934, 2874, 1764, 1642 cm ; elemental analysis calcd
=
14.0, 22.5, 24.3, 29.0, 29.1, 31.6, 33.3, 82.2, 120.8, 156.0, 170.7 ppm;
(
%) for C20
,5’-Dipentyl-5H,5’H-[4,4’]bifuranyl-2,2’-dione (3j)
Method A: A solution of nona-2,3-dienoic acid (1j;77 mg, 0.50 mmol), 2a
430 mg, 2.53 mmol), and PdCl (4 mg, 0.023 mmol) in DMA (2 mL) was
stirred at 808C for 3 h to afford 40 mg (52%) of 3j (R*,S*:R*,R*
1:1.67).
Method C: A solution of 1j (78 mg, 0.50 mmol), benzoquinone (32 mg,
30 4
H O : C 71.82, H 9.04; found: C 71.74, H 8.87.
+
EIMS: m/z (%): 362 (8.23) [M ], 57 (100); IR (KBr): n˜ =2955, 2926,
5
À1
+
+
2
856, 1748 cm ; HRMS: m/z calcd for C22
found: 363.2556.
,5’-Dioctyl-5H,5’H-[4,4’]bifuranyl-2,2’-dione (3l)
Method A: A solution of dodec-2,3-dienoic acid (1l; 97 mg, 0.50 mmol),
a (425 mg, 2.50 mmol), and PdCl (4 mg, 0.023 mmol) in DMA (2 mL)
was stirred at 808C for 3 h to afford 52 mg (54%) of 3l (R*,S*:R*,R*
1:1) and cycloisomeriztion product 5-octyl-5H-furan-2-one 5 mg (5%).
Method B: A solution of 1l (97 mg, 0.50 mmol), KI (44 mg, 0.27 mmol),
and PdCl (4 mg, 0.023 mmol) in DMA (2 mL) was stirred at 808C for
h to afford 31 mg (32%) of 3l (R*,S*:R*,R*=1:1.38).
Method C: A solution of 1l (97 mg, 0.50 mmol), benzoquinone (32 mg,
H
35
O
4
[M +1]: 363.25299;
(
2
5
=
2
2
0
.30 mmol), and PdCl
2
(4 mg, 0.023 mmol) in DMF (2 mL) was stirred at
08C for 2 h to afford 35 mg (46%) of 3j (R*,S*:R*,R*=1:1.06).
=
8
Method D: A solution of 1j (76 mg, 0.49 mmol), benzoquinone (33 mg,
2
0
.31 mmol), and PdCl
2
(4 mg, 0.023 mmol) in DMA (2 mL) was stirred at
08C for 2 h to afford 46 mg (61%) of 3j (R*,S*:R*,R*=1.19:1).
2
8
R*,R* isomer (less polar): solid, m.p. 160–1628C (ethyl acetate);
0
.30 mmol), and PdCl
2
(4 mg, 0.023 mmol) in DMF (2 mL) was stirred at
1
H NMR (300 MHz, CDCl
3
): d=6.27 (d, J=1.1 Hz, 2H), 5.27 (dd, J=
8
08C for 2 h to afford 68 mg (71%) of 3l (R*,S*:R*,R*=1:1.06).
1
1
.1, 4.8 Hz, 2H), 2.19–2.00 (m, 2H), 1.78–1.58 (m, 2H), 1.55- 1.20 (m,
2H), 0.89 ppm (t, J=4.8 Hz, 6H); C NMR (75.4 MHz, CDCl
Method D: A solution of 1l (96 mg, 0.49 mmol), benzoquinone (32 mg,
1
3
3
): d
0
.30 mmol), and PdCl
2
(4 mg, 0.023 mmol) in DMA (2 mL) was stirred at
=
13.9, 22.4, 23.9, 31.2, 33.8, 82.7, 121.2, 155.5, 170.8 ppm; EIMS: m/z
8
08C for 2 h to afford 70 mg (73%) of 3l (R*,S*:R*,R*=1:1.06).
+
(
%): 306 (2.29) [M ], 43 (100); IR (KBr): n˜ =2957, 2931, 2859,
À1
R*,R* isomer (less polar): solid, m.p. 147–1488C (ethyl acetate and petro-
1
732 cm ; elemental analysis calcd (%) for C18
H
26
O
4
: C 70.56, H 8.55;
1
leum ether); H NMR (300 MHz, CDCl
3
): d=6.19 (d, J=1.2 Hz, 2H),
found: C 70.48, H 8.46.
5
1
.19 (dd, J=1.2, 6.0 Hz, 2H), 2.09–1.92 (m, 2H), 1.67–1.49 (m, 2H),
1
R*,S* isomer (more polar): liquid; H NMR (300 MHz, CDCl
3
): d=6.22
d, J=1.5 Hz, 2H), 5.35–5.27 (m, 2H), 2.09–1.92 (m, 2H), 1.65–1.50 (m,
13
.46–1.10 (m, 24H), 0.81 ppm (t, J=6.6 Hz, 6H); C NMR (75.4 MHz,
): d=14.0, 22.6, 24.2, 29.07, 29.10, 29.2, 31.7, 33.9, 82.7, 121.2,
(
CDCl
55.5, 170.7 ppm; EIMS: m/z (%): 390 (16.40) [M ], 43 (100); IR (KBr):
3
1
3
2
H), 1.50–1.18 (m, 12H), 1.00–0.80 ppm (m, 6H); C NMR (75.4 MHz,
): d=13.8, 22.4, 24.0, 31.2, 33.3, 82.2, 120.8, 156.0, 170.7 ppm;
+
1
CDCl
EIMS: m/z (%): 306 (1.83) [M ], 43 (100); IR (neat): n˜ =2956, 2930,
3
À1
n˜ =2955, 2925, 2855, 1732 cm
: C 73.81, H 9.81; found: C 73.87, H 9.92.
R*,S* isomer (more polar): solid, m.p. 68–708C (diethyl ether); H NMR
; elemental analysis calcd (%) for
+
24 38 4
C H O
À1
+
+
2
860, 1744 cm ; HRMS: m/z calcd for C18
found: 307.1913.
,5’-Diheptyl-5H,5’H-[4,4’]bifuranyl-2,2’-dione (3k)
Method A: A solution of undeca-2,3-dienoic acid (1k; 94 mg, 0.52 mmol),
a (425 mg, 2.50 mmol), and PdCl (5 mg, 0.028 mmol) in DMA (2 mL)
was stirred at 808C for 6 h to afford 46 mg (49%) of 3k (R*,S*:R*,R*
1:1).
Method C: A solution of 1k (91 mg, 0.50 mmol), benzoquinone (32 mg,
H
27
O
4
[M +1]: 307.19039;
1
(
300 MHz, CDCl
3
): d=6.16 (s, 2H), 5.24 (d, J=6.9 Hz, 2H), 2.02–1.85
5
(
m, 2H), 1.60–1.43 (m, 2H), 1.43–1.10 (m, 24H), 0.81 ppm (t, J=6.6 Hz,
1
3
6H); C NMR (75.4 MHz, CDCl ): d=14.0, 22.6, 24.3, 29.08, 29.10, 29.3,
31.7, 33.3, 82.2, 120.8, 156.0, 170.7 ppm; EIMS: m/z (%): 390 (13.21) [M ],
43 (100); IR (KBr): n˜ =2925, 2855, 1748 cm ; HRMS: m/z calcd for
24 38 4
C H O Na [M +Na]: 413.26623; found: 413.2627. The X-ray structure
3
+
2
2
À1
+
+
=
of compound 3l is shown in Figure 2.
0
8
.15 mmol), and PdCl
08C for 2 h to afford 72 mg (80%) of 3k (R*,S*:R*,R*=1.06:1).
2
(4 mg, 0.023 mmol) in DMF (2 mL) was stirred at
(R,R)-(À)-3,3’-Dipropyl-5,5’-diphenyl-5H,5’H-[4,4’]bifuranyl-2,2’-dione
(3a)
Method D: A solution of 1k (47 mg, 0.26 mmol), benzoquinone (16 mg,
Method C: A solution of R-(À)-4-phenyl-2-propyl-2,3-butadienoic acid
0
.15 mmol), and PdCl
2
(2 mg, 0.011 mmol) in DMA (2 mL) was stirred at
(1a; 50 mg, 0.248 mmol, 97% ee), benzoquinone (17 mg, 0.157 mmol),
8
08C for 2 h to afford 39 mg (83%) of 3k (R*,S*:R*,R*=1:1.05).
2
and PdCl (2 mg, 0.011 mmol) in DMF (2 mL) was stirred at 808C for 2 h
Figure 2. ORTEP representation of the product (R*,R*)-3l.
Chem. Eur. J. 2005, 11, 2351 – 2356
www.chemeurj.org
ꢀ 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2355

S. Ma et al.
to afford 44 mg (88%, >99% ee) of (R,R)-(À)-3a. HPLC conditions:
Ed. 2003, 42, 1955; d) For an account, see: S. Ma, Acc. Chem. Res.
2003, 36, 701.
[4] For most recent coupling cyclization reaction of other functionalized
allenes, see: a) S. Ma, W. Gao, Synlett 2002, 65; b) S. Ma, N. Jiao, S.
Zhao, H. Hou, J. Org. Chem. 2002, 67, 2837; c) S. Ma, W. Gao, J.
Org. Chem. 2002, 67, 6104; d) S. Ma, H. Xie, J. Org. Chem. 2002, 67,
À1
AD column; rate: 0.7 mLmin ; eluent: hexane/iPrOH 90/10; [a]=À262
(
c=0.76 in CHCl
3
).
(
(
R,R)-(À)-3,3’-Dimethyl-5,5’-diphenyl-5H,5’H-[4,4’]bifuranyl-2,2’-dione
3b)
Method C: A solution of R-(À)-2-methyl-4-phenyl-2,3-butadienoic acid
1b; 44 mg, 0.253 mmol, 99% ee), benzoquinone (16 mg, 0.148 mmol),
and PdCl (2 mg, 0.011 mmol) in DMF (2 mL) was stirred at 808C for 2 h
6
575; e) S. Ma, W. Gao, Org. Lett. 2002, 4, 2989.
(
[
5] For the recent Pd-catalyzed reaction of allenic amides, see: a) H.
Ohno, M. Anzai, A. Toda, S. Ohishi, N. Fujii, T. Tanaka, Y. Takemo-
to, T. Ibuka, J. Org. Chem. 2001, 66, 4904; b) S.-K. Kang, K.-J. Kim,
Org. Lett. 2001, 3, 511; c) W. F. J. Karstens, D. Klomp, F. P. J. T.
Rutjes, H. Hiemstra, Tetrahedron 2001, 57, 5123.
6] For Pd-catalyzed reaction of 2-(allenyl)malonates, see: a) S. Kamijo,
Y. Yamamoto, Tetrahedron Lett. 1999, 40, 1747; b) M. Meguro, Y.
Yamamoto, J. Org. Chem. 1999, 64, 694; c) L. Besson, J. Bazin, J.
Gore, B. Cazes, Tetrahedron Lett. 1994, 35, 2881.
2
to afford 44 mg (100%, 99% ee) of (R,R)-(À)-3b. (R*,S*:R*,R*=1:25):
À1
HPLC conditions: AD column; rate: 0.7 mLmin
; eluent: hexane/
iPrOH 70/30; [a]=À325 (c=1.055 in CHCl
3
).
(
S,S)-(+)-3,3’-Dimethyl-5,5’-dinaphthy-5H,5’H-[4,4’]bifuranyl-2,2’-dione
3d)Method C: A solution of S-(+)-2-methyl-4-naphthyl-2,3-butadienoic
[
(
acid (1d; 56 mg, 0.25 mmol, 98% ee), benzoquinone (20 mg,
.189 mmol), and PdCl (2 mg, 0.011 mmol) in DMF (2 mL) was stirred
at 808C for 2 h to afford 48 mg (86%, >99% ee) of (S,S)-(+)-3d.
0
2
[
7] For a review on the palladium-catalyzed chemistry of allenes, see:
a) R. Zimmer, C. U. Dinesh, E. Nandanan, F. A. Khan, Chem. Rev.
(
R*,S*:R*,R*=1: 20); HPLC conditions: AD column; rate:
À1
0
.7 mLmin
CHCl ).
S,S)-(+)-3,3’-Dipropyl-5,5’-di(4’-bromophenyl)-5H,5’H-[4,4’]bifuranyl-
,2’-dione (3o)
; eluent: hexane/iPrOH 60/40; [a]=+210 (c=0.945 in
2
000, 100, 3067; b) S. Ma, Handbook of Organopalladium Chemistry
3
for Organic Synthesis (Ed.: E. Negishi), Wiley, New York, 2002,
p. 1491.
(
2
[8] a) For dimerization of 1,2-allenyl ketones, see: A. S. K. Hashmi, L.
Schwarz, J. H. Choi, T. M. Frost, Angew. Chem. 2000, 112, 2382;
Angew. Chem. Int. Ed. 2000, 39, 2285; b) For a recent highlight, see:
A. S. K. Hashmi, Angew. Chem. 2000, 112, 3737; Angew. Chem. Int.
Ed. 2000, 39, 3590.
[9] S. Ma, Z. Yu, Angew. Chem. 2002, 114, 1853; Angew. Chem. Int. Ed.
2002, 41, 1775.
[10] Palladium Reagents and Catalysts: New Perspectives for 21st Century
(Ed.: J. Tsuji), Wiley, Chichester (UK), 2004, pp. 27–103.
[11] S. Ma, Z. Yu. Org. Lett. 2003, 5, 1507; Corrigendum: S. Ma, Z. Yu.
Org. Lett. 2003, 5, 2581.
Method C: A solution of S-(+)-4-(4’-bromophenyl)-2-propyl-2,3-butadie-
noic acid (1o; 35 mg, 0.125 mmol, 99% ee), benzoquinone (9 mg,
0
2
.083 mmol), and PdCl (1 mg, 0.006 mmol) in DMF (1 mL) was stirred
at 808C for 2 h to afford 33 mg (94%, 98% ee) of (S,S)-(+)-3o.
À1
(
R*,S*:R*,R*=1: 24): HPLC conditions: AD column; rate: 0.7 mLmin
;
eluent: hexane/iPrOH 85/15; [a]=+194 (c=0.785 in CHCl
3
); m.p. 216–
): d=7.38 (d, J=8.4 Hz, 2H), 6.82 (d,
J=8.4 Hz, 2H), 5.81 (s, 1H), 2.33–2.21 (m, 1H), 2.14–2.00 (m, 1H), 1.59–
1
2
188C; H NMR (300 MHz, CDCl
3
1
3
1
.42 (m, 1H), 1.31–1.14 (m, 1H), 0.85 ppm (t, J=7.5 Hz, 3H); C NMR
(
1
CDCl , 75.4 MHz): d=14.1, 20.8, 27.3, 81.8, 123.9, 127.6, 131.9, 132.3,
3
+
79
33.0, 150.0, 171.6 ppm; EIMS: m/z (%): 558 (22.12) [M ( Br)], 560
[12] a) Y. Chia, F. Chang, Y. Wu, Tetrahedron Lett. 1999, 40, 7513; b) S.
Takahashi, K. Maeda, S. Hirota, T. Nakata, Org. Lett. 1999, 1, 2025;
c) R. C. Larock, B. Riefling, C. A. Fellows, J. Org. Chem. 1978, 43,
131, and references therein.
+
81
À1
(
36.58) [M ( Br)], 323 (100); IR(KBr): n˜ =1745, 1645, 1489 cm ; ele-
mental analysis calcd (%) for C26 : C 55.74, H 4.32, found C
5.69, H 4.28.
H
2 4
24Br O
5
[
13] a) J. E. Bꢁckvall, P. G. Andersson, J. Am. Chem. Soc. 1992, 114,
6
5
374; b) P. G. Andersson, J. E. Bꢁckvall, J. Org. Chem. 1991, 56,
349.
[
14] Crystal data for (R*,R*)-3l:
space group P2 /c; final R indices [I>2s(I)]: R1=0.0696, wR2
0.1602; unit cell: a=12.610(7), b=7.611(4), c=12.344(7) ꢂ, b
24 38 4 r
C H O , M =390.54, monoclinic,
Acknowledgements
1
=
=
Financial supports from the National Natural Science Foundation of
China and the Major State Basic Research Development Program
Grant No. G2000077500), and Shanghai Municipal Committee of Sci-
3
98.895(10)8,
V=1170.4(11) ꢂ ,
T=293(2) K,
wavelength:
0
=
.71073 ꢂ, Z=2, reflections collected/unique: 6154/2301 (Rint
0.1985), restraints: 7, parameters: 300. CCDC 244017 contains the
(
ence and Technology are greatly appreciated.
supplementary crystallographic data for this paper. These data can
be obtained free of charge from The Cambridge Crystallographic
Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
[
[
1] a) Allenes in Organic Synthesis (Eds.: H. F. Schuster, G. M. Coppo-
la), Wiley, New York, 1984, pp. 1–8; b) The Chemistry of Ketenes,
Allenes, and Related Compounds, Part 1 (Ed.: S. Patai), Wiley, New
York, 1980, pp. 1–154.
2] For some typical examples of axial chirality transfer, see: a) G.
Kresze, L. Kloimstein, W. Runge, Justus Liebigs Ann. Chem. 1976,
[
15] Crystal data for compound (S,S)-(+)-3o. C26
monoclinic, space group P2 , MoKa, final R indices [I>2s(I)]: R1
0.0434, wR2=0.1010; unit cell: a=9.6374(10), b=12.0918(12), c
2 4 r
H24Br O , M =560.27,
1
=
=
=
3
10.8607(11) ꢂ, b=103.264(2)8, V=1231.9(2) ꢂ , T=293(2) K, Z
2, reflections collected/unique: 7582/4800 (Rint =0.0719), no obser-
vation [I>2s(I)] 3086, parameters 300. CCDC 223809 contains the
supplementary crystallographic data for this paper. These data can
be obtained free of charge from The Cambridge Crystallographic
Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
6
4
1
4, 979; b) S. Musierowicz, A. E. Wroblewski, Tetrahedron 1978, 34,
61; c) J. A. Marshall, W. A. Wolf, E. M. Wallace, J. Org. Chem.
997, 62, 367; d) S. Ma, S. Wu, Chem. Commun. 2001, 441; e) S. Ma,
Z. Shi, Chem. Commun. 2002, 540; f) S. Ma, F. Yu, W. Gao, J. Org.
Chem. 2003, 68, 5943; g) S. Ma, Z. Yu, J. Org. Chem. 2003, 68, 6149.
3] For most recent results of the synthesis of butenolides from this
group, see: a) S. Ma, Z. Shi, S. Wu, Tetrahedron: Asymmetry 2001,
[
16] For the reports on the synthesis of bibutenolide see: a) A. Padwa,
F. R. Kinder, J. Org. Chem. 1993, 58, 21; b) F. R. Kinder, A. Padwa,
Tetrahedron Lett. 1990, 31, 6835.
[
1
2, 193; b) S. Ma, D. Duan, Y. Wang, J. Comb. Chem. 2002, 4, 239;
Received: October 23, 2004
c) S. Ma, Z. Yu, Angew. Chem. 2003, 115, 1999; Angew. Chem. Int.
Published online: February 7, 2005
2356
ꢀ 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemeurj.org
Chem. Eur. J. 2005, 11, 2351 – 2356