Concise Construction of Bicyclo[6.4.0] and -[7.4.0] Frameworks by [4+2] Cycloaddition of 3,4-Dimethylene-2,5-bis(phenylsulfonyl)cycloalk-1-enes

Article abstract of DOI:10.1002/ejoc.201500598

The thermal intermolecular [4+2] cycloadditions of vicinal bis(exo-methylene)cyclooctene with carbon dienophiles efficiently produce the bicyclo[6.4.0] framework. Similar cycloadditions with the one-carbon-homologated cyclononene derivatives result in the formation of the bicyclo[7.4.0] skeleton. Both aza- and oxadieonphiles are suitable for this [4+2] reaction and provide the corresponding hetero-Diels-Alder-type products. An efficient procedure for the preparation of bicyclo[m.4.0] frameworks (m = 6, 7) from 3,4-dimethylenecycloalkenes by Diels-Alder or hetero-Diels-Alder [4+2] cycloadditions with dienophiles is developed. The resulting oxabicyclo[7.4.0] derivatives can be converted into δ-lactones. Thus, this method enables us to construct the core bicyclic frameworks of natural products (e.g., blumiolide C).

Full text of DOI:10.1002/ejoc.201500598

FULL PAPER
DOI: 10.1002/ejoc.201500598
Concise Construction of Bicyclo[6.4.0] and -[7.4.0] Frameworks by [4+2]
Cycloaddition of 3,4-Dimethylene-2,5-bis(phenylsulfonyl)cycloalk-1-enes
Chisato Mukai,*[a] Masanobu Ueda,[a] Yasuhito Takahashi,[a] and Fuyuhiko Inagaki[a]
Keywords: Diels–Alder reaction / Fused-ring systems / Cycloaddition / Lactones
The thermal intermolecular [4+2] cycloadditions of vicinal
bis(exo-methylene)cyclooctene with carbon dienophiles ef-
rivatives result in the formation of the bicyclo[7.4.0] skeleton.
Both aza- and oxadieonphiles are suitable for this [4+2] reac-
ficiently produce the bicyclo[6.4.0] framework. Similar cyclo- tion and provide the corresponding hetero-Diels–Alder-type
additions with the one-carbon-homologated cyclononene de-
products.
Introduction
The allene functionality is now recognized as a powerful
π component in cycloisomerization and cycloaddition reac-
tions. Recent efforts from this laboratory disclosed that
bis(allene) species are suitable substrates for the construc-
tion of medium-sized carbocycles.[1] Indeed, the treatment
of 3,8-bis(phenylsulfonyl)deca-1,2,8,9-tetraene (1; n = 1)
with a catalytic amount of [RhCl(CO)dppp]2[2] [dppp = 1,3-
bis(diphenylphosphino)propane] in toluene produced the
eight-membered triene derivative 2 in 92% yield. This was
also the case when the one-carbon-homologated substrate
1 (n = 2) was exposed to similar conditions, which resulted
in the efficient formation of the nine-membered product 3
in 71% yield. The formation of the medium-sized carb-
ocycles could be tentatively rationalized in terms of the in-
termediacy of the bicyclic rhodacycle A, which would be
susceptible to 1,5-hydrogen shift (intermediate B), followed
Scheme 1. Plan for the concise construction of bicyclo[6.4.0] and
-[7.4.0] frameworks.
by reductive elimination. This method is also applicable to the construction of bicyclo[m.4.0] skeletons (m = 6 and 7)
the preparation of the seven-membered triene derivative. It and their heteroanalogues by Diels–Alder-type reactions as
would be reasonable to assume that the vicinal bis(exo- a first step in the synthesis of Xenia terpenoids (Figure 1).[6]
methylene) group of the thus-formed eight- and nine-mem-
bered carbocycles 2 and 3 should serve as the 1,3-diene moi-
ety in the Diels–Alder reactions to form the bicyclic com-
pounds 4 and 5 (Scheme 1).
Many natural products contain bicyclo[6.4.0] and -[7.4.0]
frameworks,[3] as exemplified by Xenia terpenoids such as
xeniafaraunol (bicyclo[7.4.0]),[4] blumiolide A (oxabicyclo-
[6.4.0]), and blumiolide C (oxabicyclo[7.4.0]),[5] which exhi-
bit cytotoxicity against cancer cells. Thus, our endeavor was
directed toward the development of a concise method for
Figure 1. Natural products with bicyclo[6.4.0] and -[7.4.0] frame-
works.
[a] Division of Pharmaceutical Sciences, Graduate School of
Medical Sciences, Kanazawa University
Results and Discussion
Kakuma-machi, Kanazawa 920-1192, Japan
E-mail: mukai@p.kanazawa-u.ac.jp
Our initial evaluation of the Diels–Alder-type reaction
between vicinal bis(exo-methylene) derivatives and dieno-
philes was performed with the eight-membered substrate 2
http://www.p.kanazawa-u.ac.jp/~yakuzou/indexen.html
Supporting information for this article is available on the
WWW under http://dx.doi.org/10.1002/ejoc.201500598.
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Concise Construction of Bicyclo[6.4.0] and -[7.4.0] Frameworks
and dimethyl acetylenedicarboxylate (DMAD). The treat- produced the [4+2] cycloadducts in high yields within short
ment of 2 with DMAD in toluene under reflux for 1 h pro- reaction times. In the reactions with alkenes, the [4+2] cy-
vided the bicyclo[6.4.0]dodecatriene 4a in 86% yield cloaddition proceeded in a stereospecific manner. Specifi-
(Table 1, Entry 1). When the reaction was performed in the cally, (E)-alkenes provided trans-disubstituted cyclohexene
presence of TiCl4 at 80 °C, 4a formed in a rather low yield frameworks, whereas cis-disubstituted cyclohexene skel-
(Table 1, Entry 2).[7] Microwave irradiation at 200 °C for etons were formed if (Z)-alkenes were employed. All of the
10 min was very effective for this transformation and pro- products derived from alkenes were obtained as mixtures of
duced 4a in quantitative yield (Table 1, Entry 3).[8] The two diastereoisomers with a trans or cis relationship be-
nine-membered bicyclic compound 5a (n = 2) was also tween the two substituents on the cyclohexene ring and a
formed in 99% yield from substrate 3 (n = 2) under similar phenylsulfonyl group on the eight- or nine-membered
conditions (Table 1, Entry 4).
carbocycles. The nine-membered substrate 3 tends to con-
sistently need longer reaction times than the eight-mem-
Table 1. Diels–Alder reaction of trienes 2, 3, and DMAD.
Table 2. Diels–Alder reactions of trienes 2, 3, and dienophiles.
The optimized conditions under microwave irradiation in
toluene at 200 °C were applied to the reaction of the vicinal
bis(exo-methylene) derivatives 2 and 3 with other dieno-
philes. These results are summarized in Table 2. The reac-
tions of 2 with the monosubstituted alkynes methyl pro-
piolate, acetylacetylene, and (trimethylsilyl)acetylene[9] pro-
duced the bicyclo[6.4.0]dodecatriene derivatives 4b–4d in
high yields in a nonregioselective manner (Table 2, En-
tries 1–3). Mixtures of two isomers of the one-carbon-en-
larged bicyclo[7.4.0]tridecatriene derivatives 5b–5d could be
obtained from 3 in high yields (Table 2, Entries 4–6). Elec-
tron-withdrawing substituents on the dienophilic triple
bond tend to accelerate the reaction rate. The reactions of
2 and 3 with trimethylacetylene required prolonged reaction
times (2 and 11 h) compared to those with propiolate (20
and 25 min) or acetylacetylene (15 and 25 min). This might
indicate that this cycloaddition reaction proceeds in a nor-
mal [4+2] cycloaddition fashion. 1,2-Disubstituted (E)-alk-
enes, dimethyl fumarate, and fumaronitrile provided the de-
sired products 4e,[10] 4f, 5e, and 5f in high yields (Table 2,
Entries 7–10). The reactions of 2 and 3 with dimethyl male-
ate [(Z)-alkene] proceeded readily to furnish the corre-
sponding cycloadducts 4g[11] and 5g[12] in high yields
(Table 2, Entries 11 and 12). Finally, cyclic dienophiles were
submitted to the reaction. As a result, two maleimide deriv-
atives produced the predicted four cycloadducts 4h,[13] 4i,
5h, and 5i in satisfactory yields (Table 2, Entries 13, 14, 16,
and 17). Maleic anhydride gave the desired product 4j in
88% yield (Table 2, Entry 15). It became apparent that the
Diels–Alder-type reaction of the eight- and nine-membered
vicinal bis(exo-methylene) derivatives 2 and 3 with carbon
[a] The regioisomeric ratio was determined by 1H NMR spec-
troscopy. [b] The diastereomeric ratio was determined by 1H NMR
dienophiles with one or two electron-deficient substituents spectroscopy.
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C. Mukai, M. Ueda, Y. Takahashi, F. Inagaki
FULL PAPER
Scheme 2. Step economy for the construction of bicyclo[6.4.0] derivative 4g.
bered substrate 2. This phenomenon might be rationalized proved the yield of products 5k and 5kЈ (91%), but the re-
by the more rigid conformation of the eight-membered ring gioselectivity issue was still unsolved. After screening sev-
of 2, in which the vicinal bis(exo-methylene) group is eral Lewis acids,[20] we found that the use of SnCl4 in
planar. This seems not be the case for the nine-membered CH2Cl2 at 40 °C was effective for both the chemical yield
substrate 3, in which the vicinal bis(exo-methylene) moiety and regioselectivity to furnish the 11-oxabicyclo[7.4.0]tri-
may not readily occupy a planar position; therefore, longer deca-1(9),2-diene 5k (n = 1) almost exclusively in 91% yield
reaction times are required.
(5k/5kЈ, 50:1). These conditions worked well for the eight-
As previously described, the vicinal bis(exo-methylene) membered vicinal bis(exo-methylene) derivative 2 to give
substrate 2 was prepared from commercially available 1,7- 10-oxabicyclo[6.4.0]dodeca-1(8),2-diene 4k (n = 0)[21] in
octadiyne by a stepwise procedure, which involved the for- 89% yield as a single isomer. The reaction of 2 with ethyl
mation of 6, followed by an [RhCl(CO)dppp]2-catalyzed glyoxylate[22] in the presence of SnCl4 at –60 °C proceeded
[2,3]-sigmatropic rearrangement[14] in toluene to afford the smoothly to provide the 12-oxabicyclo[7.4.0]trideca-1(9),2-
bis(sulfonylallene) 7 (Scheme 2).[15] The subsequent thermal
[4+2] cycloaddition reaction of 2 with dimethyl maleate in
toluene afforded 4g in 99% yield. We expected that the di-
rect transformation of 7 into 4g could be realized in one
operation because of the similarity of the two reaction con-
ditions. The bis(phenylsulfonylallene) 7 was directly treated
with dimethyl maleate in the presence of 5 mol-%
[RhCl(CO)dppp]2 in toluene at 200 °C under microwave ir-
radiation for 2 h to afford 4g in 88% yield.[16] Compound
4g was alternatively and more efficiently formed from 6 as
follows. A solution of 6 and dimethyl maleate in toluene
was heated at 80 °C in the presence of 5 mol-% [RhCl(CO)-
dppp]2 for 11 h, and then the reaction mixture was heated
to 200 °C under microwave irradiation for 3 h to produce
4g in 63% yield. Thus, a three-step synthesis of the bicy-
clo[6.4.0] framework from commercially available materials
was developed.
Our next endeavor was directed toward the hetero-Diels–
Alder reaction[17] of the vicinal bis(exo-methylene) deriva-
tives 2 and 3 to synthesize the core bicyclic blumiolide skel-
eton (Scheme 3). When the nine-membered triene 3 (n =
1) was exposed to diethyl oxomalonate[18] under conditions
similar to those for the reactions with oxadienophiles, the
desired oxabicyclo[7.4.0] derivatives 5k[19] and 5kЈ were ob-
tained in 55% yield as a 2:3 mixture of regioisomers. A
change of solvent to CH2Cl2 at 180 °C dramatically im- Scheme 3. Hetero-Diels–Alder reaction of trienes 2 and 3.
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Concise Construction of Bicyclo[6.4.0] and -[7.4.0] Frameworks
diene 4l (n = 0)[23] in 83% yield in a stereoselective and
Blumiolides possess δ-lactone frameworks, as indicated
regioselective manner. A similar treatment of 3 with ethyl in Figure 1. Therefore, our next task was the transformation
glyoxylate produced 5l[24] in 92% yield as a single isomer. of the tetrahydropyranyl moiety of the oxa-Diels–Alder-
For diethyl azodicarboxylate,[25] the thermal conditions (in type product 5k into a δ-lactone group (Scheme 4). The di-
toluene at 200 °C under microwave irradiation for 1.5 h) af- ethyl carboxylate moiety of the δ-lactone 5k was hydrolyzed
forded the corresponding 10,11-diazabiyclo[6.4.0] derivative with 20% aqueous potassium hydroxide in EtOH at room
4m in 82% yield. A Lewis acid was not essential to attain temperature to furnish the geminal diacid derivative, the
a high yield in this case.
subsequent exposure of which to lead tetraacetate effected
The highly regioselective formation of 4k and 5k could the smooth conversion of the geminal diacid group into a
be achieved upon treatment with Lewis acid, whereas they carbonyl functionality to produce the δ-lactone derivative
formed nonselectively without a Lewis acid. An examina- 5k in 75% overall yield.[28] A phenylsulfonyl group can be
tion of molecular models of 2 and 3 indicates that their regarded as a hydrogen surrogate and can be readily trans-
conformers for the [4+2] cycloaddition are A, in which the formed into other functional groups by conventional
vicinal bis(exo-methylene) group should be placed on the means.[29] Indeed, we could arbitrarily remove one or two
same plane (Figure 2). A phenylsulfonyl group attached to phenylsulfonyl groups of 5k as follows. Treatment of 5k
the vinyl moiety is oriented almost perpendicular to the with excess Mg in MeOH (conditions A)[30] led to the re-
plane of the vicinal bis(exo-methylene) group, whereas an moval of two phenylsulfonyl groups in one operation ac-
allylic phenylsulfonyl group takes a quasi-equatorial posi- companied by transesterification to afford the dimethyl es-
tion and is coplanar with the vicinal bis(exo-methylene) ter derivative 8 in 66% yield. On the other hand, selective
moiety. On the other hand, we imagined that a Lewis acid removal of the vinylic phenylsulfone group of 5k was
would coordinate with the two carbonyl groups of diethyl achieved by treatment with Co(acac)2 (acac = acetylaceton-
oxomalonate and ethyl glyoxylate to furnish the six- and ate), tert-butyl hydroperoxide (TBHP), and PhSiH3 in an
five-membered complexes I and II, respectively.[26] In the iPrOH/CH2Cl2 mixture (4:1).[31]
reaction with diethyl oxomalonate, I might further coordi-
nate with a phenylsulfonyl group[27] perpendicularly to the
vicinal bis(exo-methylene) group. As a result, the uncoordi-
nated carbonyl group of I would approach the vicinal
bis(exo-methylene) group of A from the face opposite to the
allylic phenylsulfonyl group to produce 4k and 5k preferen-
tially over 4kЈ and 5kЈ. The stereo- and regiocontrolled for-
mation of 4l and 5l from the reaction with ethyl glyoxylate
might also be interpreted by a similar reaction mechanism.
For ethyl glyoxylate, the Lewis acid coordinated aldehyde
moiety of II would take part in the [4+2] cycloaddition pro-
cess from its re face. An alternative approach from the si
face may suffer from unfavorable nonbonding interactions
with the residual carbon skeletons of 2 or 3; therefore, the
production of 4l and 5l is highly stereoselective.
Scheme 4. Functional-group transformations of oxabicyclo[7.4.0]
derivative 5k.
Conclusions
We have developed an efficient procedure for the forma-
tion of bicyclo[m.4.0] frameworks (m = 6, 7) through the
Diels–Alder-type [4+2] cycloaddition of 3,4-dimethylenecy-
cloalkenes with dienophiles. The hetero-Diels–Alder-type
reaction was also developed in a stereoselective and regiose-
lective manner. The tetrahydropyranyl moiety of the re-
sulting oxabicyclo[7.4.0] derivative was successfully con-
verted into a δ-lactone group. Thus, the synthetic route for
the preparation of the basic skeleton of blumiolides was
established by (1) a combination of the previously reported
rhodium-catalyzed cycloisomerization of bis(allene) species
with the oxa-Diels–Alder-type reaction of the resulting
bis(exo-methylene) derivatives and (2) the generation of the
δ-lactone moiety by simple manipulation. The application
Figure 2. Transition states of hetero-Diels–Alder reactions with
Lewis acids.
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C. Mukai, M. Ueda, Y. Takahashi, F. Inagaki
FULL PAPER
and 11-CO2Me-4b in a ratio of 3:2 or 2:3 was obtained as a color-
of these tactics to the total syntheses of blumiolides is in
progress.
less foam; the ratio was determined by 1H NMR spectroscopy
1
analysis of the crude product. IR: ν = 1717, 1308, 1150 cm–1. H
˜
NMR (400 MHz, CDCl3): δ = 7.94–7.91 (m, 2 H), 7.75–7.71 (m, 1
H), 7.68–7.64 (m, 2 H), 7.63–7.59 (m, 1 H), 7.49–7.45 (m, 2 H),
7.40 (dd, J = 8.2, 1.0 Hz, 60/100 ϫ 1 H), 7.36 (dd, J = 8.2, 1.0 Hz,
60/100 ϫ 1 H, 40/100 ϫ 2 H), 6.99 (t, J = 7.9 Hz, 1 H), 6.96–6.95
(m, 1 H), 3.78 (s, 60/100 ϫ 3 H), 3.75 (s, 40/100 ϫ 3 H), 3.72–3.65
(m, 60/100 ϫ 1 H), 3.59–3.52 (m, 40/100 ϫ 1 H), 3.50–3.33 (m, 60/
100 ϫ 3 H, 40/100 ϫ 2 H), 3.32–3.25 (m, 40/100 ϫ 1 H), 2.95–2.85
(m, 1 H), 2.40 (dt, J = 13.4, 7.6 Hz, 1 H), 1.89–1.77 (m, 3 H),
1.56–1.45 (m, 1 H), 0.98–0.87 (m, 1 H) ppm. 13C NMR (100 MHz,
CDCl3): δ = 166.5, 166.3, 142.7, 142.39, 142.35, 142.2, 139.7, 139.5,
138.4, 138.3, 134.7, 134.4, 133.70, 133.65, 133.6, 133.59, 133.56,
131.7, 129.65, 129.57, 129.1, 129.0, 128.2, 128.14, 128.07, 128.0,
127.0, 126.7, 126.6, 125.3, 66.6, 66.2, 51.83, 51.76, 31.7, 29.7, 27.80,
27.54, 27.49, 26.0, 24.2, 22.2 ppm. FAB-MS: m/z (%) = 499 (35)
[M + H]+. FAB-HRMS: calcd. for C26H27O6S2 499.1249; found
499.1253.
Experimental Section
General: Melting points were measured with a Yanagimoto micro
melting point apparatus. Infrared spectra were recorded with a Shi-
madzu FTIR-8700 spectrometer with samples in CHCl3. H NMR
1
spectra were recorded with JEOL JNM-ECS400 or JNM-ECA600
spectrometers with samples in CDCl3 or [D6]dimethyl sulfoxide
([D6]DMSO) with tetramethylsilane (for compounds with a phenyl
group), CHCl3 (δ =7.26 ppm), or DMSO (δ =2.50 ppm) as the in-
ternal reference. 13C NMR spectra were recorded with JNM-
ECS400 or JNM-ECA600 spectrometers with samples in CDCl3 (δ
=77.0 ppm). Mass spectra were recorded with JEOL JMS-SX102A
(FAB) or JMS-T100TD [direct analysis in real time (DART)] mass
spectrometers. Microwave reactions were performed in sealed reac-
tion vessels under nitrogen with a high-power, focused microwave
(Biotage initiatorTM 2.5). Commercially available anhydrous Et2O,
tetrahydrofuran (THF), CH2Cl2, toluene, and xylene were em-
ployed for the reactions. Et3N and iPr2NH were distilled from
CaH2. DMSO was distilled from CaSO4. [RhCl(CO)dppp]2 was
prepared according to literature procedures.[2] (E)-3,4-Dimethylene-
2,5-bis(phenylsulfonyl)cyclooctene and (E)-3,4-dimethylene-2,5-
bis(phenylsulfonyl)cyclononene are known compounds. [1] Silica gel
(Silica gel 60N, 40–50 μm, Kanto Chemical Co.) was used for
chromatography. All reactions were performed under N2. Organic
extracts were dried with Na2SO4. Single-crystal X-ray diffraction
data were measured with an R-AXIS RAPID II diffractometer.
CCDC-1057041 [for (7R*,10R*,11R*)-4e], -1057097 [for
(7R*,10R*,11S*)-4g], -1057098 [for (3R*,7S*,15S*)-4h], -1057099
(for 4k), -1057100 (for 4l), -1057101 [for (8R*,11S*,12R*)-5g],
-1057102 (for 5k), and -1057103 (for 5l) contain 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.
10- and 11-Acetyl-2,7-bis(phenylsulfonyl)bicyclo[6.4.0]dodeca-
1(8),2,10-triene (4c): An inseparable mixture of 10-COMe-4c and
11-COMe-4c in a ratio of 1:1 was obtained as a colorless foam; the
1
ratio was determined by H NMR spectroscopy analysis of the
crude product. IR: ν = 1686, 1672, 1308, 1148 cm–1 1H NMR
.
˜
(400 MHz, CDCl3): δ = 7.93–7.91 (m, 2 H), 7.76–7.58 (m, 4 H),
7.51–7.43 (m, 3 H), 7.34–7.32 (dd, J = 8.2, 1.0 Hz, 1 H), 7.02–6.98
(m, 1 H), 6.85 (s, 1 H), 3.83–3.76 (m, 50/100 ϫ 1 H), 3.57–3.48 (m,
1 H), 3.42–3.30 (m, 50/100 ϫ 5 H), 3.00–2.93 (m, 50/100 ϫ 1 H),
2.91–2.85 (m, 50/100 ϫ 1 H), 2.45–2.38 (m, 1 H), 2.34 (s, 50/100
ϫ 3 H), 2.31 (s, 50/100 ϫ 3 H), 1.92–1.76 (m, 3 H), 1.53–1.46 (m,
1 H), 1.00–0.87 (m, 1 H) ppm. 13C NMR (151 MHz, CDCl3): δ =
197.2, 197.1, 142.8, 142.6, 142.3, 142.0, 139.8, 139.5, 138.4, 138.3,
135.6, 135.5, 135.2, 135.0, 134.1, 133.7, 133.64, 133.59, 133.57,
131.2, 129.7, 129.5, 129.1, 129.0, 128.3, 128.13, 128.06, 127.9,
127.5, 124.9, 66.8, 66.1, 31.9, 28.6, 28.0, 27.6, 27.5, 25.3, 25.2, 25.0,
24.12, 24.09, 22.3, 22.2 ppm. FAB-MS: m/z (%) = 483 (68) [M +
H]+. FAB-HRMS: calcd. for C26H27O5S2 483.1300; found
483.1299.
General Procedure for Microwave-Assisted Diels–Alder Reactions of
Triene Derivatives: A solution of the triene derivative (0.1 mmol)
and the dienophile (1.5–10 equiv.) in toluene was heated at 200 °C
under microwave irradiation until the starting material was com-
pletely consumed (monitored by TLC). The reaction mixture was
subsequently cooled to 50 °C with compressed air, the vessel was
opened, and the toluene was evaporated. The residual oil was chro-
matographed with hexane/AcOEt or CH2Cl2/AcOEt to afford the
cyclized products. The chemical yields are summarized in Tables 1
and 2 and Schemes 2, 3, and 4.
10- and 11-Trimethylsilyl-2,7-bis(phenylsulfonyl)bicyclo[6.4.0]do-
deca-1(8),2,10-triene (4d): An inseparable mixture of 10-TMS-4d
and 11-TMS-4d in a ratio of 3:2 or 2:3 was obtained as a colorless
1
foam; the ratio was determined by H NMR spectroscopy analysis
of the crude product. IR: ν = 1308, 1148 cm–1 1H NMR
.
˜
(400 MHz, CDCl3): δ = 7.93–7.92 (m, 2 H), 7.73–7.58 (m, 4 H),
7.49–7.36 (m, 4 H), 7.00–6.93 (m, 1 H), 6.00–5.97 (m, 1 H), 3.47
(dd, J = 13.7, 9.2 Hz, 1 H), 3.34–3.10 (m, 3 H), 2.75–2.54 (m, 1
H), 2.42–2.34 (m, 1 H), 1.90–1.77 (m, 3 H), 1.53–1.40 (m, 1 H),
0.99–0.80 (m, 1 H), 0.09 (s, 40/100 ϫ 9 H), 0.02 (s, 60/100 ϫ 9 H)
ppm. 13C NMR (151 MHz, CDCl3): δ = 143.2, 143.0, 141.4, 141.3,
140.0, 139.9, 138.8, 138.7, 135.2, 135.1, 134.3, 133.5, 133.3, 131.5,
131.1, 129.53, 129.49, 129.03, 129.01, 128.22, 128.16, 128.1, 127.2,
126.7, 67.0, 66.7, 32.04, 31.95, 28.0, 27.8, 27.7, 27.5, 24.2, 24.0,
22.5, 22.4, –2.3, –2.4 ppm. MS: m/z (%) = 512 (51) [M]+. HRMS:
calcd. for C27H32O4S2Si 512.1511; found 512.1514.
10,11-Bis(methoxycarbonyl)-2,7-bis(phenylsulfonyl)bicyclo[6.4.0]-
dodeca-1(8),2,10-triene (4a): Colorless needles; m.p, 193.5–195.0 °C
(AcOEt). IR: ν = 1725, 1308, 1150 cm–1 1H NMR (400 MHz,
.
˜
CDCl3): δ = 7.93–7.90 (m, 2 H), 7.77–7.73 (m, 1 H), 7.69–7.60 (m,
3 H), 7.47 (t, J = 7.8 Hz, 2 H), 7.34–7.31 (m, 2 H), 7.01 (dd, J =
8.2, 7.8 Hz, 1 H), 3.86–3.76 (m, 1 H), 3.82 (s, 3 H), 3.79 (s, 3 H),
3.65–3.55 (m, 1 H), 3.48–3.38 (m, 1 H), 3.35 (d, J = 10.1 Hz, 1 H),
3.06 (dt, J = 22.8, 6.4 Hz, 1 H), 2.41 (dt, J = 13.7, 7.3 Hz, 1 H),
1.90–1.78 (m, 3 H), 1.54–1.44 (m, 1 H), 0.96–0.85 (m, 1 H) ppm.
13C NMR (151 MHz, CDCl3): δ = 167.4, 167.2, 142.7, 141.9, 139.4,
138.2, 133.8, 133.7, 131.9, 131.3, 131.2, 129.7, 129.1, 128.2, 128.0,
125.4, 66.1, 52.43, 52.36, 31.8, 28.2, 27.5, 24.2, 22.2 ppm. FAB-MS:
m/z (%) = 557 (75) [M + H]+. FAB-HRMS: calcd. for C28H29O8S2
557.1304; found 557.1296.
(7R*,10R*,11R*)- and (7R*,10S*,11S*)-10,11-Bis(methoxycarb-
onyl)-2,7-bis(phenylsulfonyl)bicyclo[6.4.0]dodeca-1(8),2-diene (4e):
Each diastereomer was isolated by column chromatography (hex-
ane/AcOEt, 3:2) for analysis. The structure of the major isomer
(7R*,10R*,11R*)-4e was unambiguously determined by X-ray crys-
tallography (CCDC-1057041). (7R*,10R*,11R*)-4e: Colorless
10- and 11-Methoxycarbonyl-2,7-bis(phenylsulfonyl)bicyclo[6.4.0]do-
deca-1(8),2,10-triene (4b): An inseparable mixture of 10-CO2Me-4b
plates; m.p. 191.0–192.0 °C (Et O). IR: ν = 1734, 1308, 1148 cm–1.
˜
2
1H NMR (600 MHz, CDCl3): δ = 7.98–7.97 (m, 2 H), 7.73–7.70
4416
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© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2015, 4412–4422

Concise Construction of Bicyclo[6.4.0] and -[7.4.0] Frameworks
(m, 1 H), 7.66–7.64 (m, 2 H), 7.60–7.57 (m, 1 H), 7.46–7.43 (m, 2
27.5, 25.1, 24.2, 22.3 ppm. DART-MS: m/z (%) = 559 (100) [M +
H), 7.30 (dd, J = 8.2, 1.0 Hz, 2 H), 6.96 (dd, J = 8.6, 7.6 Hz, 1 H), H]+. DART-HRMS: calcd. for C28H31O8S2 559.1460; found
3.75 (s, 3 H), 3.70 (s, 3 H), 3.33 (d, J = 9.6 Hz, 1 H), 3.31–3.27 (m, 559.1455. (7R*,10R*,11S*)-4g: Colorless plates; m.p. 191.0–
1 H), 3.24 (dt, J = 11.7, 5.8 Hz, 1 H), 3.07 (q, J = 5.8 Hz, 1 H),
2.88–2.85 (m, 1 H), 2.73 (dd, J = 18.6, 5.2 Hz, 1 H), 2.38–2.33 (m,
1 H), 2.22 (m, 1 H), 1.87–1.81 (m, 3 H), 1.71–1.56 (m, 1 H), 0.95–
192.0 °C (Et O). IR: ν = 1732, 1308, 1148 cm–1 1H NMR
.
˜
2
(400 MHz, CDCl3): δ = 7.92–7.90 (m, 2 H), 7.73–7.70 (m, 1 H),
7.66–7.59 (m, 3 H), 7.48–7.45 (m, 2 H), 7.40 (dd, J = 8.2, 1.4 Hz,
0.87 (m, 1 H) ppm. 13C NMR (151 MHz, CDCl3): δ = 173.9, 173.1, 2 H), 6.94 (dd, J = 8.9, 7.6 Hz, 1 H), 3.70 (s, 3 H), 3.64 (s, 3 H),
142.8, 141.9, 139.6, 138.5, 133.60, 133.52, 129.5, 129.0, 128.2, 3.42 (d, J = 10.0 Hz, 1 H), 3.36–3.33 (m, 1 H), 3.15 (dd, J = 18.6,
127.1, 66.8, 52.3, 52.2, 39.7, 39.4, 28.9, 27.1, 25.5, 23.6, 22.4 ppm.
DART-MS: m/z (%) = 559 (100) [M + H]+. DART-HRMS: calcd. 1 H), 2.36–2.26 (m, 2 H), 1.87–1.79 (m, 3 H), 1.66–1.58 (m, 1 H),
for C28H31O8S2 559.1460; found 559.1455. (7R*,10S*,11S*)-4e:
0.89–0.82 (m, 1 H) ppm. 13C NMR (101 MHz, CDCl3): δ = 172.8,
5.8 Hz, 1 H), 3.01–2.95 (m, 2 H), 2.86 (ddt, J = 18.6, 5.8, 2.7 Hz,
Colorless needles; m.p. 232.0–234.0 °C (Et O). IR: ν = 1736, 1308, 172.7, 143.1, 142.3, 139.9, 138.5, 133.61, 133.57, 129.6, 129.1,
˜
2
1150 cm–1. H NMR (400 MHz, CDCl3): δ = 7.91–7.89 (m, 2 H), 128.3, 128.1, 127.8, 66.8, 52.02, 51.97, 39.7, 39.3, 28.4, 27.4, 26.6,
1
7.78–7.59 (m, 4 H), 7.47 (t, J = 7.8 Hz, 2 H), 7.36–7.34 (m, 2 H),
6.98 (dd, J = 8.7, 7.3 Hz, 1 H), 3.73 (s, 3 H), 3.70 (s, 3 H), 3.38
(dd, J = 18.3, 5.5 Hz, 1 H), 3.32 (d, J = 10.1 Hz, 1 H), 3.01 (dt, J
= 10.5, 5.5 Hz, 1 H), 2.93–2.85 (m, 1 H), 2.79–2.67 (m, 2 H), 2.42
(dt, J = 13.2, 7.3 Hz, 1 H), 2.12–2.04 (m, 1 H), 1.88–1.73 (m, 3 H),
1.58–1.43 (m, 1 H), 0.96–0.85 (m, 1 H) ppm. 13C NMR (151 MHz,
CDCl3): δ = 174.4, 173.8, 142.6, 141.8, 139.3, 138.3, 134.0, 133.7,
129.7, 129.1, 128.2, 128.1, 127.7, 66.4, 52.2, 52.1, 41.4, 40.8, 31.3,
27.9, 27.3, 24.3, 22.3 ppm. DART-MS: m/z (%) = 559 (100) [M +
H]+. DART-HRMS: calcd. for C28H31O8S2 559.1460; found
559.1459.
23.6, 22.5 ppm. DART-MS: m/z (%) = 559 (100) [M + H]+. DART-
HRMS: calcd. for C28H31O8S2 559.1460; found 559.1454.
(3R*,7S*,15R*)- and (3R*,7S*,15S*)-N-Phenyl-10,15-bis(phenyl-
sulfonyl)-5-azatricyclo[7.6.0.03,7]pentadeca-1(9),10-diene-4,6-dione
(4h): Each diastereomer was isolated by column chromatography
(hexane/AcOEt, 1:1) for analysis. The structure of minor isomer
(3R*,7S*,15S*)-4h was unambiguously determined by X-ray crys-
tallography (CCDC-1057098). (3R*,7S*,15R*)-4h: Colorless
plates; m.p. 148.0–149.5 °C (acetone/hexane). IR: ν = 1717, 1308,
˜
1
1150 cm–1. H NMR (400 MHz, CDCl3): δ = 7.83–7.81 (m, 2 H),
7.69–7.65 (m, 1 H), 7.61–5.67 (m, 1 H), 7.53–7.35 (m, 11 H), 7.01
(7R*,10R*,11R*)- and (7R*,10S*,11S*)-10,11-Dicyano-2,7-bis- (dd, J = 8.7, 7.3 Hz, 1 H), 3.36 (d, J = 9.6 Hz, 1 H), 3.19–3.11 (m,
(phenylsulfonyl)bicyclo[6.4.0]dodeca-1(8),2-diene (4f): A mixture of 3 H), 3.00–2.92 (m, 2 H), 2.79 (dd, J = 15.6, 6.0 Hz, 1 H), 2.48 (dt,
(7R*,10R*,11R*)- and (7R*,10S*,11S*)-4f in a ratio of 3:2 or 2:3 J = 13.3, 7.3 Hz, 1 H), 1.93 (dt, J = 14.2, 4.1 Hz, 1 H), 1.87–1.80
1
was obtained as a colorless foam; the ratio was determined by H
(m, 1 H), 1.73–1.64 (m, 1 H), 1.52–1.42 (m, 1 H), 1.02–0.94 (m, 1
H) ppm. 13C NMR (101 MHz, CDCl3): δ = 176.9, 176.7, 142.8,
141.6, 139.6, 138.4, 137.1, 133.8, 133.5, 131.8, 130.8, 129.6, 129.1,
129.0, 128.5, 128.4, 128.2, 126.5, 66.8, 39.6, 39.0, 28.0, 27.9, 24.8,
NMR spectroscopy analysis of the crude product. IR: ν = 2251,
˜
1310, 1150 cm–1. H NMR (600 MHz, CDCl3): δ = 7.94–7.91 (m,
1
2 H), 7.78–7.74 (m, 1 H), 7.71–7.68 (m, 2 H), 7.65–7.62 (m, 1 H),
7.50–7.47 (m, 2 H), 7.36–7.34 (m, 2 H), 7.10–7.07 (dd, J = 8.9, 23.8, 22.1 ppm. DART-MS: m/z (%) = 588 (41) [M + H]+. DART-
7.6 Hz, 40/100 ϫ 1 H), 7.04–7.02 (t, J = 7.6 Hz, 60/100 ϫ 1 H),
HRMS: calcd. for C32H30NO6S2 588.1515; found 588.1523.
3.60–3.55 (m, 1 H), 3.42–3.41 (m, 40/100 ϫ 1 H), 3.37 (d, J = (3R*,7S*,15S*)-4h: Colorless plates; m.p. 151.0–153.0 °C (AcOEt).
1
9.6 Hz, 60/100 ϫ 1 H), 3.35–3.32 (m, 40/100 ϫ 1 H), 3.31–3.27 (m,
1 H), 3.27–3.22 (m, 60/100 ϫ 2 H, 40/100 ϫ 1 H), 3.03–2.96 (m, 1
IR: ν = 1713, 1308, 1150 cm–1. H NMR (400 MHz, CDCl ): δ =
˜
3
7.89–7.87 (m, 2 H), 7.76–7.71 (m, 1 H), 7.67–7.58 (m, 3 H), 7.48–
H), 2.61 (dt, J = 19.2, 4.5 Hz, 40/100 ϫ 1 H), 2.51 (dd, J = 17.8, 7.40 (m, 4 H), 7.38–7.33 (m, 3 H), 7.20–7.18 (m, 2 H), 6.87 (dd, J
3.8 Hz, 60/100 ϫ 1 H), 2.48 (dd, J = 7.6, 5.5 Hz, 40/100 ϫ 1 H), = 8.7, 7.8 Hz, 1 H), 3.56 (dd, J = 16.5, 1.8 Hz, 1 H), 3.41–3.33 (m,
2.45–2.39 (m, 60/100 ϫ 1 H), 2.01–1.84 (m, 3 H), 1.59–1.46 (m, 1
2 H), 3.23 (d, J = 10.1 Hz, 1 H), 3.09 (dd, J = 15.1, 1.8 Hz, 1 H),
H), 1.00–0.87 (m, 1 H) ppm. 13C NMR (151 MHz, CDCl3): δ = 2.77–2.70 (m, 2 H), 2.33 (dt, J = 12.8, 7.8 Hz, 1 H), 1.90–1.84 (m,
143.8, 143.3, 141.2, 140.5, 138.7, 137.9, 134.1, 134.03, 134.01, 1 H), 1.77–1.70 (m, 1 H), 1.42–1.31 (m, 2 H), 0.94–0.76 (m, 1 H)
134.0, 132.8, 132.2, 130.0, 129.9, 129.25, 129.23, 128.27, 128.25, ppm. 13C NMR (101 MHz, CDCl3): δ = 178.0, 177.7, 142.1, 141.8,
128.2, 128.1, 126.0, 125.7, 118.2, 118.1, 117.6, 117.5, 66.18, 66.15,
139.9, 138.4, 138.1, 133.8, 133.7, 131.7, 129.7, 129.19, 129.16,
30.5, 29.7, 28.5, 27.6, 27.24, 27.18, 26.9, 26.5, 26.3, 26.1, 25.9, 25.0, 129.1, 128.5, 128.3, 128.1, 125.5, 67.0, 39.2, 39.0, 28.3, 27.4, 25.0,
24.3, 22.2, 22.1 ppm. DART-MS: m/z (%) = 493 (48) [M + H]+. 22.7, 22.0 ppm. FAB-MS: m/z (%) = 588 (76) [M + H]+. FAB-
DART-HRMS: calcd. for C26H25N2O4S2 493.1256; found HRMS: calcd. for C32H30NO6S2 588.1515; found 588.1514.
493.1272.
(3R*,7S*,15S*)- and (3R*,7S*,15R*)-10,15-Bis(phenylsulfonyl)-5-
(7R*,10S*,11R*)- and (7R*,10R*,11S*)-10,11-Bis(methoxycarb- azatricyclo[7.6.0.03,7]pentadeca-1(9),10-diene-4,6-dione (4i): Each
onyl)-2,7-bis(phenylsulfonyl)bicyclo[6.4.0]dodeca-1(8),2-diene (4g):
Each diastereomer was isolated by column chromatography (hex-
ane/AcOEt, 3:2) for analysis. The structure of the minor isomer
(7R*,10R*,11S*)-4g was unambiguously determined by X-ray crys-
diastereomer was isolated by column chromatography (CH2Cl2/Ac-
OEt 10:1) for analysis. (3R*,7S*,15S*)-4: Colorless powder; m.p.
290.5–292.0 °C (CH Cl ). IR (KBr, neat film): ν = 1705, 1304,
˜
2
2
1150 cm–1. 1H NMR (600 MHz, [D6]DMSO): δ = 11.22 (s, 1 H),
tallography (CCDC-1057097). (7R*,10S*,11R*)-4g: Colorless 7.86–7.79 (m, 3 H), 7.74–7.69 (m, 3 H), 7.59 (t, J = 7.8 Hz, 2 H),
plates; m.p. 157.0–158.0 °C (Et O). IR: ν = 1732, 1308, 1150 cm–1.
7.21 (d, J = 7.8 Hz, 2 H), 6.93 (t, J = 7.8 Hz, 1 H), 3.13–2.95 (m,
˜
2
1H NMR (400 MHz, CDCl3): δ = 7.95–7.93 (m, 2 H), 7.72–7.56 3 H), 2.90–2.83 (m, 1 H), 2.75 (dd, J = 14.7, 7.1 Hz, 1 H), 2.52–
(m, 4 H), 7.45 (m, 2 H), 7.35–7.33 (m, 2 H), 7.01 (dd, J = 8.7, 2.19 (m, 3 H), 1.72–1.60 (m, 3 H), 1.46–1.34 (m, 1 H), 0.83–0.75
7.8 Hz, 1 H), 3.75 (s, 3 H), 3.72 (s, 3 H), 3.59–3.53 (m, 1 H), 3.37
(m, 1 H) ppm. 13C NMR (101 MHz, CDCl3): δ = 179.9, 143.1,
(d, J = 9.6 Hz, 1 H), 3.21–3.18 (m, 1 H), 3.10–3.02 (m, 1 H), 2.79– 140.3, 139.2, 138.2, 137.3, 134.1, 133.9, 129.8, 129.7, 129.5, 127.8,
2.71 (m, 2 H), 2.42 (dt, J = 13.3, 7.8 Hz, 1 H), 2.27–2.21 (m, 1 H), 127.7, 66.7, 28.0, 27.4, 24.4, 23.3, 21.2 ppm. FAB-MS: m/z (%) =
1.97–1.91 (dt, J = 14.7, 3.7 Hz, 1 H), 1.87–1.73 (m, 2 H), 1.60–1.44
512 (89) [M + H]+. FAB-HRMS: calcd. for C26H26NO6S2 512.1202;
(m, 1 H), 1.04–0.93 (m, 1 H) ppm. 13C NMR (101 MHz, CDCl3): found 512.1205. (3R*,7S*,15R*)-4i: Colorless powder; m.p. 300 °C
δ = 172.7, 172.2, 142.5, 142.1, 139.5, 138.5, 134.1, 133.5, 133.4,
(CH Cl ). IR (KBr, neat film): ν = 1705, 1304, 1150 cm–1. 1H NMR
˜
2 2
129.5, 129.0, 128.25, 128.19, 127.4, 66.6, 52.1, 52.0, 39.8, 39.2, 30.4,
(600 MHz, [D6]DMSO): δ = 11.40 (s, 1 H), 7.91–7.85 (m, 3 H),
Eur. J. Org. Chem. 2015, 4412–4422
© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
4417

C. Mukai, M. Ueda, Y. Takahashi, F. Inagaki
FULL PAPER
7.79–7.74 (m, 3 H), 7.63 (t, J = 7.6 Hz, 2 H), 7.25 (dd, J = 8.2, HRMS: calcd. for C26H28O7S2 516.1277; found 516.1270. The
0.7 Hz, 2 H), 6.93 (t, J = 8.2 Hz, 1 H), 3.29–3.23 (m, 2 H), 3.18 structure of 4l (CCDC-1057100) was unambiguously determined
(dd, J = 15.8, 1.7 Hz, 1 H), 2.94 (d, J = 10.0 Hz, 1 H), 2.85 (dd, J by X-ray crystallography.
= 15.1, 2.1 Hz, 1 H), 2.63–2.60 (m, 1 H), 2.52–2.42 (m, 2 H), 1.76–
N,NЈ-Bis(ethoxycarbonyl)-2,7-bis(phenylsulfonyl)-10,11-diazabi-
1.73 (m, 1 H), 1.71–1.67 (m, 1 H), 1.41–1.35 (m, 1 H), 1.16–1.12
(m, 1 H), 0.75–0.68 (m, 1 H) ppm. 13C NMR (101 MHz, CDCl3):
δ = 181.1, 180.9, 142.6, 140.7, 139.3, 138.0, 137.3, 134.1, 134.0,
130.0, 129.5, 128.6, 127.8, 127.6, 66.5, 54.9, 28.1, 26.6, 24.8, 22.7,
21.4 ppm. FAB-MS: m/z (%) = 512 (76) [M + H]+. FAB-HRMS:
calcd. for C26H26NO6S2 512.1202; found 512.1208.
cyclo[6.4.0]dodeca-1(8),2-diene (4m): Colorless amorphous solid.
IR: ν = 1717, 1310, 1150 cm–1. The 1H NMR spectrum of 4m
˜
showed that it is a mixture of rotational isomers in a ratio of 5:1
1
in CDCl3. H NMR (600 MHz, CDCl3): δ = 7.91 (d, J = 7.8 Hz,
2 H ϫ 84/100), 7.84 (d, J = 7.3 Hz, 2 H ϫ 16/100), 7.73–7.69 (m,
1 H), 7.65–7.59 (m, 3 H), 7.50–7.43 (m, 4 H), 7.09 (t, J = 7.8 Hz,
1 H ϫ 84/100), 6.95 (t, J = 7.3 Hz, 1 H ϫ 16/100), 5.19 (d, J =
17.9 Hz, 1 H ϫ 84/100), 5.07 (d, J = 18.8 Hz, 1 H ϫ 16/100), 4.74
(d, J = 18.8 Hz, 1 H), 4.35–4.14 (m, 4 H), 3.98 (d, J = 18.8 Hz, 1
H), 3.60 (d, J = 17.9 Hz, 1 H), 3.21 (d, J = 10.1 Hz, 1 H), 2.45 (dt,
J = 12.8, 7.8 Hz, 1 H ϫ 84/100), 2.40–2.42 (m, 1 H ϫ 16/100), 2.03
(m, 2 H), 1.77 (m, 2 H), 1.32 (t, J = 6.9 Hz, 3 H), 1.24 (t, J =
6.9 Hz, 3 H), 1.00–0.88 (m, 1 H) ppm. 13C NMR (151 MHz,
CD3OD): δ = 157.2, 156.94, 156.85, 156.8, 147.3, 145.5, 141.5,
140.8, 140.7, 140.2, 139.4, 139.3, 139.2, 135.5, 135.4, 135.3, 134.6,
134.0, 131.2, 131.1, 130.6, 130.5, 129.5, 129.4, 129.3, 129.2, 128.9,
128.2, 67.1, 66.9, 64.3, 64.2, 47.2, 44.9, 29.7, 29.5, 28.63, 28.57,
26.9, 25.2, 25.1, 23.10, 23.05, 22.9, 14.93, 14.89, 14.84, 14.77 ppm.
FAB-MS: m/z (%) = 589 (69) [M + H]+. FAB-HRMS: calcd. for
C26H33N2O8S2 589.1678; found 589.1670.
(3R*,7S*,15R*)- and (3R*,7S*,15S*)-10,15-Bis(phenylsulfonyl)-5-
oxatricyclo[7.6.0.03,7]pentadeca-1(9),10-diene-4,6-dione (4j): A mix-
ture of (3R*,7S*,15R*)- and (3R*,7S*,15S*)-4j in a ratio of 1:1
1
was obtained as a colorless foam; the ratio was determined by H
NMR spectroscopy analysis of the crude product. IR: ν = 1784,
˜
1
1308, 1150 cm–1. H NMR (400 MHz, CDCl3): δ = 7.87–7.84 (m,
2 H), 7.87–7.73 (m, 1 H), 7.68–7.59 (m, 3 H), 7.49–7.43 (m, 2 H),
7.34–7.29 (m, 2 H), 7.00 (dd, J = 8.2, 7.3 Hz, 1 H ϫ 50/100), 6.91
(dd, J = 9.2, 8.2 Hz, 1 H ϫ 50/100), 3.58–3.48 (m, 3 H ϫ 50/100),
3.32–3.27 (m, 1 H ϫ 50/100), 3.25–3.16 (m, 1 H), 3.14–3.09 (m, 3
H ϫ 50/100), 2.87–2.83 (m, 1 H), 2.78–2.71 (m, 3 H ϫ 50/100),
2.50–2.45 (m, 1 H), 1.93 (dt, J = 14.2, 4.1 Hz, 1 H ϫ 50/100), 1.85–
1.76 (m, 2 H), 1.68–1.59 (m, 1 H ϫ 50/100), 1.48–1.24 (m, 2 H),
1.04–0.94 (m, 50/100 ϫ 1 H), 0.82–0.71 (m, 50/100 ϫ 1 H) ppm.
13C NMR (101 MHz, CDCl3): δ = 173.5, 173.0, 171.8, 171.5, 142.8,
142.6, 141.5, 141.4, 139.8, 139.3, 138.11, 138.07, 137.0, 134.0,
133.9, 133.8, 133.7, 130.1, 129.8, 129.75, 129.3, 129.2, 128.32,
128.29, 128.1, 128.0, 66.7, 66.6, 40.0, 39.9, 39.5, 39.4, 28.5, 28.1,
27.5, 27.3, 25.4, 24.2, 23.9, 22.9, 22.1, 21.9 ppm. MS: m/z (%) =
512 (40) [M]+. HRMS: calcd. for C26H24O7S2 512.0964; found
512.0962.
11,12-Bis(methoxycarbonyl)-2,8-bis(phenylsulfonyl)bicyclo[7.4.0]-
trideca-1(9),2,11-triene (5a): Colorless plates; m.p. 178.0–180.5 °C
(AcOEt). IR: ν = 1724, 1306, 1146 cm–1 1H NMR (400 MHz,
.
˜
CDCl3): δ = 8.02–7.98 (m, 4 H), 7.71–7.55 (m, 6 H), 7.02 (dd, J =
10.5, 6.9 Hz, 1 H), 4.25 (dd, J = 10.1, 4.1 Hz, 1 H), 4.00–3.62 (m,
1 H), 3.80 (s, 3 H), 3.68 (s, 3 H), 3.26 (dt, J = 23.4, 7.3 Hz, 1 H),
2.55 (dt, J = 23.4, 7.3 Hz, 1 H), 2.38–2.31 (m, 1 H), 2.22 (ddd, J
= 23.3, 10.1, 7.3 Hz, 1 H), 2.04–1.96 (m, 1 H), 1.85–1.67 (m, 3 H),
1.58–1.50 (m, 1 H), 1.37–1.32 (m, 1 H), 1.21–1.13 (m, 1 H) ppm.
13C NMR (101 MHz, CDCl3): δ = 167.4, 166.8, 143.9, 142.5, 138.8,
138.7, 134.0, 133.7, 132.07, 132.05, 130.1, 129.5, 129.1, 129.0,
128.9, 127.5, 68.5, 52.4, 52.2, 32.0, 29.4, 28.4, 27.9, 26.9, 25.5 ppm.
FAB-MS: m/z (%) = 593 (78) [M + Na]+. FAB-HRMS: calcd. for
C29H30NaO8S2 593.1280; found 593.1275.
11,11-Diethoxycarbonyl-2,7-bis(phenylsulfonyl)-10-oxabicyclo-
[6.4.0]dodeca-1(8),2-diene (4k): Colorless plates; m.p. 189.5–
190.0 °C (AcOEt/hexane). IR: ν = 1741, 1310, 1150 cm–1. 1H NMR
˜
(600 MHz, CDCl3): δ = 8.03–8.01 (m, 2 H), 7.75–7.72 (m, 1 H),
7.68–7.65 (m, 2 H), 7.61–7.58 (m, 1 H), 7.44 (t, J = 7.6 Hz, 2 H),
7.27–7.26 (m, 2 H), 7.04 (dd, J = 8.6, 7.6 Hz, 1 H), 4.86 (dt, J =
17.9, 2.4 Hz, 1 H), 4.62 (dt, J = 17.9, 2.4 Hz, 1 H), 4.40–4.21 (m,
4 H), 3.65 (dt, J = 17.5, 2.4 Hz, 1 H), 3.15 (d, J = 10.0 Hz, 1 H),
2.63 (dt, J = 17.5, 2.4 Hz, 1 H), 2.41 (dt, J = 13.1, 7.6 Hz, 1 H),
1.96–1.91 (m, 1 H), 1.83–1.78 (m, 2 H), 1.46–1.39 (m, 1 H), 1.35
(t, J = 7.2 Hz, 3 H), 1.28 (t, J = 7.2 Hz, 3 H), 0.88–0.80 (m, 1 H)
ppm. 13C NMR (101 MHz, CDCl3): δ = 167.9, 167.2, 143.4, 140.7,
139.4, 137.8, 133.8, 133.6, 133.5, 129.6, 129.1, 128.3, 128.2, 125.2,
79.2, 65.2, 62.8, 62.6, 62.4, 32.3, 26.9, 24.7, 22.4, 14.1, 14.0 ppm.
FAB-MS: m/z (%) = 611 (98) [M + Na]+. FAB-HRMS: calcd. for
C29H32NaO9S2 611.1385; found 611.1395. The structure of 4k
(CCDC-1057099) was unambiguously determined by X-ray crystal-
lography.
11- and 12-Methoxycarbonyl-2,8-bis(phenylsulfonyl)bicyclo[7.4.0]tri-
deca-1(9),2,11-triene (5b): An inseparable mixture of 11-CO2Me-5b
and 12-CO2Me-5b in a ratio of 3:2 or 2:3 was obtained as a color-
less solid; the ratio was determined by 1H NMR spectroscopy
1
analysis of the crude product. IR: ν = 1718, 1306, 1148 cm–1. H
˜
NMR (600 MHz, CDCl3): δ = 8.05–8.02 (m, 4 H), 7.69–7.55 (m, 6
H), 7.04–7.00 (m, 1 H), 6.91–6.90 (m, 40/100 ϫ 1 H), 6.69–6.68
(m, 60/100 ϫ 1 H), 4.33 (dd, J = 10.3, 4.1 Hz, 40/100 ϫ 1 H), 4.27
(dd, J = 10.3, 4.1 Hz, 60/100 ϫ 1 H), 3.76 (s, 60/100 ϫ 3 H), 3.66
(s, 40/100 ϫ 3 H), 3.62–3.52 (m, 1 H), 3.23–3.16 (m, 60/100 ϫ 1
H), 3.11 (ddt, J = 20.1, 7.2, 4.1 Hz, 40/100 ϫ 1 H), 2.49–2.31 (m,
2 H), 2.13–1.98 (m, 2 H), 1.83–1.75 (m,2 H), 1.72–1.65 (m, 1 H),
1.59–1.53 (m, 1 H), 1.34–1.27 (m, 1 H), 1.19–1.11 (m, 1 H) ppm.
13C NMR (151 MHz, CDCl3): δ = 166.6, 166.1, 144.7, 144.6, 142.0,
141.8, 139.2, 139.1, 138.9, 138.8, 134.8, 134.1, 134.01, 133.96,
133.8, 133.65, 133.58, 131.9, 129.42, 129.36, 129.19, 129.16, 129.12,
129.05, 129.01, 127.4, 126.9, 126.3, 68.9, 68.6, 51.9, 51.7, 32.1, 30.1,
29.5, 29.4, 28.0, 27.94, 27.91, 27.14, 27.12, 26.0, 25.61, 25.57 ppm.
MS: m/z (5) = 512 (81) [M]+. HRMS: calcd. for C27H28O6S2
512.1327; found 512.1325.
(7R*,10S*)-10-Ethoxycarbonyl-2,7-bis(phenylsulfonyl)-11-oxabi-
cyclo[6.4.0]dodeca-1(8),2-diene (4l): Colorless plates; m.p. 156.5–
157.5 °C (AcOEt/hexane). IR: ν = 1740, 1308, 1150 cm–1. 1H NMR
˜
(400 MHz, CDCl3): δ = 7.92–7.89 (m, 2 H), 7.77–7.33 (m, 1 H),
7.69–7.65 (m, 2 H), 7.64–7.60 (m, 1 H), 7.49–7.45 (m, 2 H), 7.37–
7.35 (m, 2 H), 7.01 (dd, J = 8.7, 7.3 Hz, 1 H), 4.83 (dt, J = 17.4,
2.7 Hz, 1 H), 4.49 (t, J = 5.5 Hz, 1 H), 4.29–4.16 (m, 3 H), 3.31 (d,
J = 10.1 Hz, 1 H), 3.01 (ddt, J = 18.3, 5.5, 2.7 Hz, 1 H), 2.83–2.77
(m, 1 H), 2.42–2.35 (m, 1 H), 1.89–1.80 (m, 3 H), 1.63–1.53 (m, 1
H), 1.30 (t, J = 7.3 Hz, 3 H), 0.97–0.86 (m, 1 H) ppm. 13C NMR 11- and 12-Acetyl-2,8-bis(phenylsulfonyl)bicyclo[7.4.0]trideca-
(101 MHz, CDCl3): δ = 170.8, 143.8, 139.9, 139.3, 138.3, 133.8, 1(9),2,11-triene (5c): An inseparable mixture of 11-COMe-5c and
133.7, 132.1, 129.7, 129.1, 128.2, 128.0, 127.8, 70.9, 66.2, 65.6, 61.4,
12-COMe-5c in a ratio of 1:1 was obtained as a colorless solid; the
ratio was determined by H NMR spectroscopy analysis of the
1
27.2, 26.7, 23.7, 22.3, 14.2 ppm. MS: m/z (%) = 516 (7) [M]+.
4418
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© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2015, 4412–4422

Concise Construction of Bicyclo[6.4.0] and -[7.4.0] Frameworks
crude product. IR: ν = 1670, 1306, 1146 cm–1. 1H NMR (400 MHz,
4 H), 7.74–7.62 (m, 4 H), 7.60–7.57 (m, 2 H), 7.09 (dd, J = 11.3,
CDCl3): δ = 8.09–7.97 (m, 4 H), 7.71–7.53 (m, 6 H), 7.04–6.99 (m, 6.5 Hz, 60/100ϫ 1 H), 7.05 (dd, J = 10.3, 7.2 Hz, 40/100ϫ 1 H),
˜
1 H), 6.83–8.51 (m, 50/100 ϫ 1 H), 6.60–6.58 (m, 50/100 ϫ 1 H),
4.37 (dd, J = 10.5, 4.1 Hz, 50/100 ϫ 1 H), 4.21 (dd, J = 10.5,
4.1 Hz, 50/100 ϫ 1 H), 3.72–3.60 (m, 50/100 ϫ 1 H), 3.51–3.40 (m,
50/100 ϫ 1 H), 3.24–3.11 (m, 1 H), 2.55–2.26 (m, 3 H), 2.29 (s, 50/
4.24 (dd, J = 11.0, 6.5 Hz, 40/100ϫ 1 H), 4.21 (dd, J = 8.2, 5.2 Hz,
60/100ϫ 1 H), 3.37–3.25 (m, 60/100ϫ 2 H, 40/100ϫ 1 H), 3.20
(dd, J = 12.7, 6.5 Hz, 40/100ϫ 1 H), 3.12–3.10 (m, 60/100ϫ 1 H),
2.97 (dd, J = 12.7, 5.8 Hz, 40/100ϫ 1 H), 2.84 (d, J = 18.6 Hz, 1
100 ϫ 3 H), 2.23 (s, 50/100 ϫ 3 H), 2.13–1.91 (m, 1 H), 1.81–1.50 H), 2.42–2.34 (m, 1 H), 2.33–2.28 (m, 60/100ϫ 1 H), 2.08–2.02 (m,
(m, 4 H), 1.35–1.22 (m, 1 H), 1.18–1.09 (m, 1 H) ppm. 13C NMR 1 H), 1.96–1.91 (m, 60/100ϫ 1 H, 40/100ϫ 2 H), 1.90–1.78 (m, 60/
(101 MHz, CDCl3): δ = 197.2, 197.1, 144.6, 144.5, 142.4, 141.6, 100ϫ 2 H, 40/100ϫ 1 H), 1.74–1.56 (m, 2 H), 1.52–1.45 (m, 60/
139.2, 139.1, 139.0, 138.7, 135.7, 135.3, 134.4, 134.2, 133.94, 100ϫ 1 H), 1.39–1.29 (m, 60/100ϫ 1 H, 40/100ϫ 2 H), 1.15–1.10
133.89, 133.6, 133.5, 131.3, 129.6, 129.4, 129.3, 129.12, 129.06,
129.01, 128.95, 128.91, 127.1, 69.0, 68.5, 32.3, 29.6, 29.3, 28.9,
28.05, 28.00, 27.9, 27.1, 27.0, 25.5, 25.4, 25.3, 25.0 ppm. FAB-MS:
m/z (%) = 519 (70) [M + Na]+ . FAB-HRMS: calcd. for
C27H28NaO5S2 519.1276; found 519.1268.
(m, 40/100ϫ 1 H) ppm. 13C NMR (151 MHz, CDCl3): δ = 144.0,
143.2, 143.1, 142.3, 138.5, 138.4, 138.3, 134.3, 134.2, 133.9, 133.8,
133.44, 133.36, 130.0, 129.9, 129.2, 129.1, 129.03, 128.95, 127.8,
127.4, 118.5, 118.2, 117.5, 117.2, 77.2, 69.1, 68.5, 31.1, 29.2, 29.1,
28.5, 27.8, 27.6, 27.2, 26.54, 26.48, 26.3, 26.2, 26.1, 25.7, 25.2 ppm.
DART-MS: m/z (%) = 507 (100) [M + H]+. DART-HRMS: calcd.
for C27H26N2O4S2 507.1412; found 507.1394.
11- and 12-Trimethylsilyl-2,8-bis(phenylsulfonyl)bicyclo[7.4.0]tri-
deca-1(9),2,11-triene (5d): An inseparable mixture of 11-TMS-5d
and 12-TMS-5d in a ratio of 1:1 was obtained as a colorless foam;
(8R*,11R*,12S*)- and (8R*,11S*,12R*)-11,12-Bis(methoxycarb-
onyl)-2,8-bis(phenylsulfonyl)bicyclo[7.4.0]trideca-1(9),2-diene (5g):
Each diastereomer was isolated by column chromatography (hex-
ane/AcOEt, 3:2) for analysis. The structure of the minor isomer
(8R*,11S*,12R*)-5g was unambiguously determined by X-ray crys-
tallography (CCDC-1057101). (8R*,11R*,12S*)-5g: Colorless
1
the ratio was determined by H NMR spectroscopy analysis of the
crude product. IR: ν = 1304, 1146 cm–1 1H NMR (400 MHz,
.
˜
CDCl3): δ = 8.06–7.99 (m, 4 H), 7.67–7.53 (m, 6 H), 7.04–6.96 (m,
1 H), 5.91 (s, 50/100 ϫ 1 H), 5.72 (m, 50/100 ϫ 1 H), 4.32–4.25
(m, 1 H), 3.35–3.14 (m, 1 H), 2.99–2.89 (m, 1 H), 2.35–2.26 (m, 1
H), 2.23–1.97 (m, 2 H), 1.92–1.49 (m, 5 H), 1.38–1.07 (m, 2 H),
0.07 (s, 50/100 ϫ 9 H), –0.15 (s, 50/100 ϫ 9 H) ppm. 13C NMR
(101 MHz, CDCl3): δ = 145.3, 145.2, 141.3, 140.9, 139.43, 139.40,
139.2, 139.0, 135.7, 134.25, 134.15, 133.8, 133.7, 133.4, 133.13,
133.05, 129.3, 129.19, 129.16, 129.1, 129.03, 128.97, 128.9, 69.2,
32.6, 32.5, 29.5, 29.2, 27.94, 27.90, 27.84, 27.76, 27.2, 27.1, 25.7,
25.6, –2.4, –2.6 ppm. MS: m/z (%) = 526 (100) [M]+. HRMS: calcd.
for C28H34O4S2Si 526.1668; found 526.1665.
plates; m.p. 193.0–195.5 °C (AcOEt). IR: ν = 1734, 1306,
˜
1
1146 cm–1. H NMR (400 MHz, CDCl3): δ = 8.07–8.03 (m, 4 H),
7.69–7.55 (m, 6 H), 6.95 (dd, J = 10.5, 6.4 Hz, 1 H), 4.25 (dd, J =
10.1, 4.1 Hz, 1 H), 3.65 (s, 3 H), 3.63 (s, 3 H), 3.22 (dt, J = 6.4,
4.1 Hz, 1 H), 3.05–2.97 (m, 1 H), 2.84–2.78 (m, 1 H), 2.67–2.62 (m,
1 H), 2.29–2.21 (m, 1 H), 2.11–2.00 (m, 2 H), 1.93–1.84 (m, 1 H),
1.78–1.60 (m, 2 H), 1.51 (dd, J = 18.3, 5.5 Hz, 1 H), 1.45–1.37 (m,
2 H), 1.16–1.08 (m, 1 H) ppm. 13C NMR (151 MHz, CDCl3): δ =
173.0, 172.7, 144.2, 142.2, 139.1, 138.9, 134.0, 133.9, 133.5, 129.7,
129.3, 129.2, 129.1, 129.0, 69.2, 51.9, 39.5, 39.0, 29.2, 28.4, 27.3,
26.99, 26.97, 25.6 ppm. MS: m/z (%) = 572 (24) [M]+. HRMS:
calcd. for C29H32O8S2 572.1539; found 572.1543. (8R*,11S*,12R*)-
(8R*,11R*,12R*)- and (8R*,11S*,12S*)-11,12-Bis(methoxy-
carbonyl)-2,8-bis(phenylsulfonyl)bicyclo[7.4.0]trideca-1(9)-diene (5e):
An i n s ep a rabl e m i x t u re o f ( 8R * , 1 1 R * , 1 2 R * ) - 5 e a n d
(8R*,11S*,12S*)-5e in ratio of 7:3 was obtained as a colorless
5g: Colorless plates; m.p. 153.5–155.0 °C (AcOEt/hexane). IR: ν =
˜
1
1732, 1306, 1146 cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.97–7.91
(m, 4 H), 7.69–7.52 (m, 6 H), 7.01 (dd, J = 10.6, 6.9 Hz, 1 H), 4.11
(dd, J = 10.1, 4.1 Hz, 1 H), 3.76 (s, 3 H), 3.66 (s, 3 H), 3.30–3.23
(m, 1 H), 2.96–2.92 (m, 2 H), 2.62–2.56 (m, 1 H), 2.39–2.31 (m, 1
H), 2.20–2.17 (m, 1 H), 2.03–1.90 (m, 2 H), 1.86–1.72 (m, 3 H),
1.60–1.53 (m, 1 H), 1.38–1.29 (m, 1 H), 1.24–1.18 (m, 1 H) ppm.
13C NMR (151 MHz, CDCl3): δ = 172.4, 172.1, 144.6, 142.7, 129.3,
139.2, 134.4, 133.7, 133.4, 129.5, 129.3, 129.1, 129.0, 128.9, 69.3,
52.1, 52.0, 39.4, 39.1, 30.7, 29.5, 28.3, 26.8, 25.9, 25.6 ppm. MS:
m/z (%) = 572 (100) [M]+. HRMS: calcd. for C29H32O8S2 572.1539;
found 572.1533.
foam; the ratio was determined by H NMR spectroscopy analysis
of the crude product. IR: ν = 1736, 1306, 1146 cm–1. 1H NMR
˜
(600 MHz, CDCl3): δ = 8.06–7.95 (m, 4 H), 7.74–7.54 (m, 6 H),
7.00–6.96 (m, 1 H), 4.27 (dd, J = 10.3, 4.1 Hz, 30/100 ϫ 1 H), 4.13
(dd, J = 10.3, 4.1 Hz, 70/100 ϫ 1 H), 3.72 (s, 30/100 ϫ 3 H), 3.70
(s, 70/100 ϫ 3 H), 3.63 (s, 70/100 ϫ 3 H), 3.58 (s, 30/100 ϫ 3 H),
3.16–3.12 (m, 70/100 ϫ 1 H), 2.96 (dt, J = 8.9, 5.8 Hz, 70/100 ϫ 1
H), 2.82 (dt, J = 8.9, 6.2 Hz, 70/100 ϫ 1 H), 2.77–2.73 (m, 70/100
ϫ 1 H), 2.60–2.55 (m, 30/100 ϫ 1 H), 2.45–2.40 (m, 70/100 ϫ 1
H), 2.37–2.30 (m, 1 H), 2.06–1.97 (m, 1 H), 1.91 (dd, J = 17.9,
5.8 Hz, 70/100 ϫ 1 H), 1.84–1.71 (m, 70/100 ϫ 2 H, 30/100 ϫ 7
H), 1.68–1.63 (m, 70/100 ϫ 1 H, 30/100 ϫ 1 H), 1.60–1.50 (m, 70/
100 ϫ 1 H), 1.45 (dd, J = 17.5, 5.2 Hz, 30/100 ϫ 1 H), 1.40–1.35
(m, 70/100 ϫ 1 H), 1.32–1.28 (m, 30/100ϫ 1 H), 1.19–1.12 (m, 1
H) ppm. 13C NMR (101 MHz, CDCl3): δ = 174.2, 174.0, 173.6,
173.1, 144.8, 143.8, 142.3, 141.4, 139.03, 138.96, 138.4, 134.4,
134.1, 133.9, 133.6, 133.5, 129.6, 129.4, 129.25, 129.21, 129.15,
129.1, 129.05, 128.99, 128.9, 69.3, 68.7, 52.2, 52.13, 52.06, 51.9,
41.2, 40.9, 40.6, 40.1, 32.2, 31.2, 29.3, 29.2, 28.1, 27.98, 27.94, 27.4,
27.2, 26.7, 25.51, 25.48 ppm. MS: m/z (%) = 572 (33) [M]+. HRMS:
calcd. for C29H32O8S2 572.1539; found 572.1532.
(3R*,7S*,16R*)- and (3R*,7S*,16S*)-N-Phenyl-10,16-bis(phenyl-
sulfonyl)-5-azatricyclo[7.7.0.03,7]hexadeca-1(9),10-dien-4,6-dion
(5h): Each diastereomer was isolated by column chromatography
(hexane/AcOEt 1:1) for analysis. (3R*,7S*,16R*)-5h: Colorless
plates; m.p. 154.0–156.0 °C (AcOEt/hexane). IR: ν = 1713, 1306,
˜
1146 cm–1. 1H NMR (600 MHz, CDCl3): δ = 8.02 (dd, J = 8.2,
1.0 Hz, 2 H), 7.97–7.95 (m, 2 H), 7.73–7.70 (m, 1 H), 7.66–7.61 (m,
3 H), 7.56 (t, J = 7.6 Hz, 2 H), 7.44–7.42 (m, 2 H), 7.37–7.34 (m,
1 H), 7.26–7.24 (m, 2 H), 6.95 (dd, J = 10.3, 6.5 Hz, 1 H), 4.11
(dd, J = 10.0, 3.4 Hz, 1 H), 3.38–3.34 (m, 1 H), 3.05 (dd, J = 16.5,
(8R*,11R*,12R*)- and (8S*,11R*,12R*)-11,12-Dicyano-2,8-bis- 4.5 Hz, 1 H), 2.98–2.94 (m, 2 H), 2.30–2.25 (m, 1 H), 2.23 (dd, J
(phenylsulfonyl)bicyclo[7.4.0]trideca-1(9),2-diene (5f): A mixture of
(8R*,11R*,12R*)-5f and (8S*,11R*,12R*)-5f in a ratio of 3:2 or
2:3 was obtained as a colorless foam; the ratio was determined by
= 15.8, 4.5 Hz, 1 H), 2.01 (ddd, J = 15.8, 7.9, 1.4 Hz, 1 H), 1.93–
1.87 (m, 1 H), 1.79–1.73 (m, 1 H), 1.65–1.58 (m, 3 H), 1.46–1.40
(m, 1 H), 1.17–1.11 (m, 1 H) ppm. 13C NMR (151 MHz, CDCl3):
δ = 177.90, 177.87, 144.2, 142.0, 139.1, 138.9, 137.7, 134.1, 133.7,
131.7, 131.5, 129.5, 129.2, 129.11, 129.06, 128.9, 128.5, 125.6, 69.3,
1H NMR spectroscopy analysis of the crude product. IR: ν = 2251,
˜
1
1308, 1146 cm–1. H NMR (600 MHz, CDCl3): δ = 8.02–7.93 (m,
Eur. J. Org. Chem. 2015, 4412–4422
© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
4419

C. Mukai, M. Ueda, Y. Takahashi, F. Inagaki
FULL PAPER
38.8, 38.6, 29.8, 28.6, 28.4, 26.4, 24.7, 24.5 ppm. FAB-MS: m/z (%)
= 1744, 1308, 1148 cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.95
= 624 (49) [M + Na]+. FAB-HRMS: calcd. for C33H31NNaO6S2 (d, J = 7.3 Hz, 2 H), 7.82 (d, J = 7.3 Hz, 2 H), 7.71–7.59 (m, 4 H),
624.1491; found 624.1494. (3R*,7S*,16S*)-5h: Colorless plates;
m.p. 141.0–143.0 °C (AcOEt/hexane). IR: ν = 1715, 1308,
7.54 (t, J = 7.3 Hz, 2 H), 7.12 (dd, J = 11.4, 5.5 Hz, 1 H), 4.37–
4.18 (m, 4 H), 3.93 (dd, J = 7.3, 3.7 Hz, 1 H), 3.85–3.73 (m, 2 H),
˜
1
1146 cm–1. H NMR (600 MHz, CDCl3): δ = 7.95–7.91 (m, 4 H), 3.20–3.05 (m, 2 H), 2.26–2.18 (m, 1 H), 2.02–1.87 (m, 3 H), 1.75–
7.65–7.61 (m, 2 H), 7.54–7.46 (m, 6 H), 7.41–7.36 (m, 3 H), 7.03
(dd, J = 10.3, 7.2 Hz, 1 H), 4.15 (dd, J = 11.0, 4.1 Hz, 1 H), 3.20
(dt, J = 10.0, 7.6 Hz, 1 H), 3.11–3.06 (m, 2 H), 2.84 (dd, J = 16.2,
1.60 (m, 2 H), 1.47–1.37 (m, 1 H), 1.31 (t, J = 6.9 Hz, 3 H), 1.26
(t, J = 6.9 Hz, 3 H), 1.20–1.10 (m, 1 H) ppm. 13C NMR (101 MHz,
CDCl3): δ = 167.9, 167.2, 145.7, 140.3, 138.8, 138.6, 134.1, 133.6,
7.6 Hz, 1 H), 2.46–2.41 (m, 1 H), 2.26 (dd, J = 19.8, 7.6 Hz, 1 H), 132.0, 129.7, 129.1, 128.82, 128.78, 128.2, 78.9, 69.7, 65.1, 62.5,
2.10 (dd, J = 15.8, 7.6 Hz, 1 H), 2.08–2.02 (m, 1 H), 1.82–1.74 (m, 62.4, 29.0, 28.0, 25.9, 25.4, 14.04, 13.98 ppm. DART-MS: m/z (%)
2 H), 1.71–1.65 (m, 2 H), 1.27–1.23 (m, 1 H), 1.19–1.13 (m, 1 H) = 603 (100) [M + H]+. DART-HRMS: calcd. for C30H35O9S2
ppm. 13C NMR (151 MHz, CDCl3): δ = 176.9, 176.7, 144.5, 143.1,
139.4, 139.0, 137.1, 133.9, 133.6, 132.6, 131.8, 129.4, 129.13,
129.07, 128.9, 128.8, 128.6, 126.6, 68.8, 39.1, 38.9, 30.7, 28.9, 28.5,
27.1, 24.7, 24.6 ppm. FAB-MS: m/z (%) = 624 (82) [M + Na]+.
FAB-HRMS: calcd. for C33H31NNaO6S2 624.1491; found
624.1493.
603.1723; found 603.1722.
(8R*,11S*)-11-Ethoxycarbonyl-2,8-bis(phenylsulfonyl)-12-oxabi-
cyclo[7.4.0]trideca-1(9),2-diene (5l): Colorless plates; m.p. 167.0–
168.0 °C (EtOH). IR: ν = 1738, 1306, 1146 cm–1 1H NMR
.
˜
(400 MHz, CDCl3): δ = 8.04–8.00 (m, 4 H), 7.72–7.56 (m, 6 H),
7.10 (dd, J = 10.5, 6.9 Hz, 1 H), 4.29–4.16 (m, 4 H), 3.82–3.78 (m,
1 H), 3.19–3.10 (m, 2 H), 2.61–2.54 (m, 1 H), 2.38–2.31 (m, 1 H),
2.06–1.97 (m, 1 H), 1.91–1.36 (m, 3 H), 1.59–1.51 (m, 1 H), 1.43–
1.36 (m, 1 H), 1.30 (t, J = 6.9 Hz, 3 H), 1.16–1.08 (m, 1 H) ppm.
13C NMR (101 MHz, CDCl3): δ = 170.7, 143.8, 141.7, 138.9, 138.4,
134.2, 133.7, 132.6, 130.1, 129.4, 129.21, 129.16, 128.9, 71.2, 68.4,
66.6, 61.5, 29.2, 27.8, 27.2, 26.9, 25.2, 14.2 ppm. FAB-MS: m/z (%)
= 531 (71) [M]+. FAB-HRMS: calcd. for C27H31O7S2 531.1511;
found 531.1504. The structure of 5l (CCDC-1057103) was unam-
biguously determined by X-ray crystallography.
(3R*,7S*,16R*)- and (3R*,7S*,16S*)-10,16-Bis(phenylsulfonyl)-5-
azatricyclo[7.7.0.03,7]hexadeca-1(9),10-dien-4,6-dion (5i): Each dia-
stereomer was isolated by column chromatography (CH2Cl2/Ac-
OEt, 10:1) for analysis. (3R*,7S*,16R*)-5i: Colorless powder; m.p.
250.0–252.0 °C (CH Cl ). IR: ν = 1728, 1306, 1146 cm–1. 1H NMR
˜
2
2
(600 MHz, CDCl3): δ = 7.96–7.93 (m, 4 H), 7.69–7.63 (m, 2 H),
7.59–7.54 (m, 4 H), 7.00 (dd, J = 10.0, 6.9 Hz, 1 H), 4.15 (dd, J =
10.7, 3.8 Hz, 1 H), 3.15 (dd, J = 16.5, 7.9 Hz, 1 H), 3.04–2.99 (m,
1 H), 2.90–2.87 (m, 1 H), 2.56 (ddd, J = 16.2, 8.9, 1.0 Hz, 1 H),
2.44–2.39 (m, 1 H), 2.12 (dd, J = 15.5, 7.6 Hz, 1 H), 2.06–2.00 (m,
1 H), 1.82–1.74 (m, 3 H), 1.70–1.61 (m, 2 H), 1.25–1.21 (m, 1 H),
1.18–1.12 (m, 1 H) ppm. 13C NMR (101 MHz, CDCl3): δ = 177.69,
177.67, 144.7, 142.5, 139.2, 138.9, 137.5, 134.0, 133.7, 132.5, 129.5,
129.2, 129.0, 128.9, 68.9, 40.4, 40.2, 30.6, 28.9, 28.5, 27.0, 24.8,
24.3 ppm. FAB-MS: m/z (%) = 548 (77) [M + Na]+. FAB-HRMS:
calcd. for C2 7 H2 7 NNaO6 S2 548.1178; found 548.1186.
(3R*,7S*,16S*)-5i: Colorless needles; m.p. 246.0–248.5 °C
1,10-Bis(phenylsulfinyloxy)deca-2,8-diyne (6): To a solution of 2,8-
decadiyne-1,10-diol (166 mg, 1.00 mmol) and Et3N (830 μL,
6.0 mmol) in THF (5.0 mL) was added a solution of PhS(O)Cl
(10 mL, 6.0 mmol, 0.6 m in toluene) at –78 °C. The reaction mix-
ture was stirred at room temperature for 1.5 h, quenched by the
addition of water, and extracted with CH2Cl2. The extract was
washed with water and brine, dried, and concentrated to dryness.
The residual oil was chromatographed with hexane/AcOEt (5:2) to
(CH Cl ). IR: ν = 1730, 1306, 1146 cm–1. 1H NMR (400 MHz,
˜
2
2
afford 6 (380 mg, 92%) as a colorless oil. IR: ν = 2235, 1130 cm–1.
˜
CDCl3): δ = 8.02–7.94 (m, 5 H), 7.72–7.54 (m, 6 H), 6.95 (dd, J =
10.5, 7.3 Hz, 1 H), 4.10 (dd, J = 10.5, 3.7 Hz, 1 H), 3.24 (dt, J =
12.4, 6.4 Hz, 1 H), 2.88 (d, J = 6.4 Hz, 2 H), 2.85–2.79 (m, 1 H),
2.35–2.28 (m, 1 H), 2.18 (s, 2 H), 2.13 (dd, J = 15.6, 4.6 Hz, 1 H),
1.96–1.88 (m, 2 H), 1.73–1.50 (m, 2 H), 1.19–1.16 (m, 1 H), 1.12–
1.08 (m, 1 H) ppm. 13C NMR (101 MHz, CDCl3): δ = 178.9, 178.8,
144.1, 142.3, 139.2, 138.9, 137.6, 134.1, 133.7, 131.8, 129.5, 129.20,
129.16, 128.9, 69.0, 40.0, 39.9, 29.9, 28.6, 28.4, 26.6, 24.6,
24.4 ppm. FAB-MS: m/z (%) = 548 (69) [M + Na]+. FAB-HRMS
calcd. for C27H27NNaO6S2 548.1178; found 548.1179.
1H NMR: δ = 7.77–7.72 (m, 4 H), 7.59–7.52 (m, 6 H), 4.62 (dt, J
= 15.6, 2.3 Hz, 2 H), 4.47 (dt, J = 15.6, 2.3 Hz, 2 H), 2.22–2.18 (m,
4 H), 1.59–1.52 (m, 4 H) ppm. 13C NMR: δ = 144.2, 132.3, 129.0,
125.3, 88.6, 74.2, 52.8, 27.2, 18.3 ppm. DART-MS: m/z (%) = 415
(25) [M + H]+. DART-HRMS: calcd. for C22H23O4S2 415.1038;
found 415.1041.
12,12-Bis(ethoxycarbonyl)-11-oxabicyclo[7.4.0]trideca-1(9),2-diene
(8): To a solution of 5m (60.2 mg, 0.100 mmol) in MeOH (0.50 mL)
was added Mg (24 mg, 1.0 mmol) at room temperature, and the
mixture was stirred at same temperature for 4 h. The reaction was
quenched by the addition of aqueous HCl (10%), and the mixture
was extracted with CH2Cl2. The extract was washed with water
and brine, dried, and concentrated to dryness. The residual oil was
chromatographed with hexane/AcOEt (4:1) to afford 8 (19.5 mg,
12,12-Bis(ethoxycarbonyl)-2,8-bis(phenylsulfonyl)-11-oxabicyclo-
[7.4.0]trideca-1(9),2-diene (5k): Colorless plates; m.p. 132.5–
133.5 °C (AcOEt/hexane). IR: ν = 1743, 1308, 1148 cm–1. 1H NMR
˜
(400 MHz, CDCl3): δ = 8.04–8.02 (m, 2 H), 7.80–7.77 (m, 2 H),
7.71–7.65 (m, 1 H), 7.64–7.59 (m, 3 H), 7.55–6.97 (m, 2 H), 7.07
(dd, J = 11.0, 6.4 Hz, 1 H), 4.97 (dt, J = 17.4, 2.3 Hz, 1 H), 4.48
(dt, J = 17.4, 2.3 Hz, 1 H), 4.33–4.16 (m, 4 H), 3.94 (dd, J = 9.2,
4.6 Hz, 1 H), 2.43–2.30 (m, 3 H), 2.12–2.03 (m, 1 H), 1.85–1.70 (m,
3 H), 1.41–1.35 (m, 2 H), 1.29 (t, J = 7.3 Hz, 3 H), 1.28–1.19 (m,
4 H) ppm. 13C NMR (151 MHz, CDCl3): δ = 168.0, 166.9, 144.3,
142.8, 139.1, 138.4, 133.84, 133.80, 133.7, 129.5, 129.12, 129.10,
128.8, 126.8, 79.0, 68.0, 63.0, 62.48, 62.46, 32.9, 28.6, 27.8, 26.9,
25.4, 14.1, 14.0 ppm. DART-MS: m/z (%) = 603 (100) [M + H]+.
DART-HRMS: calcd. for C30H35O9S2 603.1723; found 603.1707.
The structure of 5k (CCDC-1057102) was unambiguously deter-
mined by X-ray crystallography.
1
66%) as a colorless oil. H NMR: δ = 5.82 (d, J = 10.3 Hz, 1 H),
5.68 (dt, J = 10.3, 8.2 Hz, 1 H), 4.28–4.26 (m, 2 H), 3.81 (s, 6 H),
2.61 (s, 2 H), 2.08–2.04 (m, 2 H), 1.98 (t, J = 5.8 Hz, 2 H), 1.56–
1.53 (m, 2 H), 1.48–1.44 (m, 2 H), 1.41–1.37 (m, 2 H) ppm. 13C
NMR: δ = 168.7, 133.8, 131.0, 129.3, 124.9, 79.9, 66.3, 53.14, 53.13,
32.6, 30.6, 29.5, 28.4, 26.7, 25.0 ppm. DART-MS: m/z (%) = 295
(44) [M + H]+. DART-HRMS: calcd. 295.1546 for C16H23O5;
found 295.1545.
12,12-Bis(ethoxycarbonyl)-8-phenylsulfonyl-11-oxabicyclo[7.4.0]tri-
deca-1(9),2-diene (9): TBHP (47.9 μL, 3.12 m), PhSiH3 (18.5 μL,
0.15 mmol), and Co(acac)2 (35.8 mg, 0.13 mmol) were added to a
solution of 5m (60.2 mg, 0.100 mmol) in iPrOH/CH2Cl2 (4:1;
2.5 mL) at room temperature. The reaction mixture was stirred at
11,11-Bis(ethoxycarbonyl)-2,8-bis(phenylsulfonyl)-12-oxabicyclo-
[7.4.0]trideca-1(9),2-diene (5kЈ): Colorless amorphous solid. IR: ν
˜
4420
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© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2015, 4412–4422

Concise Construction of Bicyclo[6.4.0] and -[7.4.0] Frameworks
[5]
[6]
A. A. H. El-Gamal, C.-Y. Chiang, S.-H. Huang, S.-K. Wang,
C.-Y. Duh, J. Nat. Prod. 2005, 68, 1336–1340.
same temperature for 1 h, quenched by the addition of aqueous
NH4Cl, and extracted with CH2Cl2. The extract was washed with
water and brine, dried, and concentrated to dryness. The residual
oil was chromatographed with hexane/AcOEt (2:1) to afford 9
(38.4 mg, 83%) as a colorless amorphous solid. 1H NMR: δ = 7.83–
7.75 (m, 2 H), 7.58–7.54 (m, 1 H), 7.49–7.45 (m, 2 H), 5.71 (dd, J
= 17.9, 10.3 Hz, 1 H), 5.01 (d, J = 10.3 Hz, 1 H), 4.39 (dd, J =
12.0, 3.4 Hz, 1 H), 4.31–4.13 (m, 4 H), 3.91 (dd, J = 29.9, 17.2 Hz,
2 H), 2.95–2.80 (m, 2 H), 2.17–2.07 (m, 2 H), 2.00–1.95 (m, 1 H),
1.91–1.87 (m, 1 H), 1.81–1.75 (m, 1 H), 1.56–1.47 (m, 2 H), 1.26–
1.18 (m, 6 H), 0.95–0.90 (m, 1 H) ppm. 13C NMR: δ = 168.0, 167.7,
138.7, 137.9, 137.5, 133.5, 128.9, 128.1, 124.5, 122.0, 79.8, 67.1,
64.9, 62.4, 62.2, 30.2, 27.8, 24.3, 23.7, 14.1, 14.0 ppm. DART-MS:
m/z (%) = 463 (100) [M + H]+. DART-HRMS: calcd. for
C22H31O7S 463.1791; found 463.1791.
a) P. Lu, J. Kuang, S. Ma, Synlett 2010, 2, 227–230; b) N. C.
Nicolaou, S. A. Snyder, T. Montagon, G. Vissilikogiannakis,
Angew. Chem. Int. Ed. 2002, 41, 1668–1698; Angew. Chem.
2002, 114, 1742.
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1988, 110, 1238–1256; b) W. R. Roush, H. R. Gillis, A. I. Ko,
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5015–5017.
a) T. Razzaq, J. M. Kremsner, C. O. Kappe, J. Org. Chem. 2008,
73, 6321–6329; b) A. De La Hoz, Á. Díaz-Ortiz, A. Moreno,
Chem. Soc. Rev. 2005, 34, 164–178; c) J.-C. Monbaliu, J.
Marchand-Brynaert, Synthesis 2009, 1876–1880; d) L. Perreux,
A. Loupy, Tetrahedron 2001, 57, 9199–9223; e) C. O. Kappe,
Angew. Chem. Int. Ed. 2004, 43, 6250–6284; Angew. Chem.
2004, 116, 6408.
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2047; d) G. Hilt, W. Hess, K. Harms, Org. Lett. 2006, 15, 3287–
3290.
The stereochemistry of the major isomer 4e (7R*,10R*,11R*)
was unambiguously confirmed by X-ray crystallographic
analysis (CCDC-1057041).
The stereochemistry of the minor isomer 4g (7R*,10R*,11S*)
was unambiguously confirmed by X-ray crystallographic
analysis (CCDC-1057097).
The stereochemistry of the minor isomer 5g (8R*,11S*,12R*)
was unambiguously confirmed by X-ray crystallographic
analysis (CCDC-1057101).
The stereochemistry of the minor isomer 4h (3R*,7S*,15S*)
was unambiguously confirmed by X-ray crystallographic
analysis (CCDC-1057098).
a) B. Bowden, R. C. Cookson, H. A. Davis, J. Chem. Soc. Fara-
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[7]
[8]
2,8-Bis(phenylsulfonyl)-11-oxabicyclo[7.4.0]trideca-1(9),2-diene-12-
one (10): To a solution of 5k (60.2 mg, 0.100 mmol) in EtOH
(0.50 mL) was added aqueous KOH (20%, 0.50 mL) at room tem-
perature. The reaction mixture was stirred at same temperature for
0.5 h, quenched by the addition of aqueous HCl (10%), and ex-
tracted with CH2Cl2. The extract was washed with water and brine,
dried, and concentrated to dryness to afford the crude diol. To a
solution of the crude diol in CH3CN (0.30 mL) were added
Pb(OAc)4 (97.5 mg, 0.22 mmol) and pyridine (17.7 μL, 0.22 mmol)
at room temperature. The reaction mixture was stirred at 50 °C for
0.5 h, quenched by the addition of brine, and extracted with
CH2Cl2. The extract was washed with water and brine, dried, and
concentrated to dryness. The residual oil was chromatographed
with hexane/AcOEt (1:1) to afford 10 (36.8 mg, 75%) as a colorless
[9]
[10]
[11]
[12]
[13]
[14]
1
amorphous solid. H NMR: δ = 7.93–7.92 (m, 4 H), 7.75–7.68 (m,
2 H), 7.64–7.58 (m, 4 H), 7.11 (dd, J = 10.1, 3.2 Hz, 1 H), 5.30–
5.19 (m, 1 H), 5.12 (d, J = 16.0 Hz, 1 H), 4.17 (dd, J = 10.1, 4.1 Hz,
1 H), 2.59 (d, J = 19.2 Hz, 1 H), 2.50–2.37 (m, 2 H), 2.05–1.96 (m,
1 H), 1.86–1.73 (m, 3 H), 1.64–1.59 (m, 1 H), 1.47–1.37 (m, 1 H),
1.32–1.21 (m, 1 H) ppm. 13C NMR: δ = 168.2, 143.7, 142.1, 138.6,
137.9, 134.4, 134.21, 134.16, 129.7, 129.5, 129.4, 128.94, 128.88,
67.5, 66.5, 35.4, 29.9, 28.2, 27.0, 25.0 ppm. DART-MS: m/z (%) =
473 (40) [M + H]+. DART-HRMS: calcd. for C24H35O6S2 473.1093;
found 473.1094.
[15]
[16]
Acknowledgments
[17]
[18]
This work was supported by a Grant-in-Aid for Scientific Research
from the Ministry of Education, Culture, Sports, Science, and Tech-
nology (Japan), for which we are thankful.
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[19]
[20]
The structure of 5k (CCDC-1057102) was unambiguously de-
termined by X-ray crystallographic analysis.
Although other Lewis acids [BF3·OEt2, AlCl3, and Cu(OTf)2]
were screened, the desired product could not be detected. For
TiCl4, the regioselectivity was similar to that with SnCl4 (5k/
5kЈ, 10:1), but the chemical yield was rather low (46%).
The structure of 4k (CCDC-1057099) was unambiguously de-
termined by X-ray crystallographic analysis.
a) M. Nilsen, C. B. Jacobsen, N. Holub, M. W. Paixão, K. A.
Jørgensen, Angew. Chem. Int. Ed. 2010, 49, 2668–2679; Angew.
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C. R. Nevill, J. P. Reddy, Angew. Chem. Int. Ed. 2007, 46, 915–
918; Angew. Chem. 2007, 119, 933.
The structure of 4l (CCDC-1057100) was unambiguously de-
termined by X-ray crystallographic analysis.
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Lett. 1994, 47, 8855–8858.
The structure of 5l (CCDC-1057103) was unambiguously de-
termined by X-ray crystallographic analysis.
Eur. J. Org. Chem. 2015, 4412–4422
© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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4421

C. Mukai, M. Ueda, Y. Takahashi, F. Inagaki
FULL PAPER
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Received: May 11, 2015
Published Online: June 2, 2015
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Eur. J. Org. Chem. 2015, 4412–4422