AlCl3-mediated tandem Friedel-Crafts reactions of vinylidenecyclopropanes with acyl chlorides: a facile synthetic method for the construction of 1-[2-(2,2-diarylvinyl)-1-phenyl-3H-inden-5-yl]ethanone derivatives

Article abstract of DOI:10.1016/j.tet.2008.02.003

AlCl₃-mediated tandem Friedel-Crafts reaction of vinylidenecyclopropanes with acyl chlorides produced the corresponding 1-[2-(2,2-diarylvinyl)-1-phenyl-3H-inden-5-yl]ethanone derivatives in moderate to good yields under mild conditions within short reaction time.

Full text of DOI:10.1016/j.tet.2008.02.003

Available online at www.sciencedirect.com
Tetrahedron 64 (2008) 3315e3321
www.elsevier.com/locate/tet
AlCl3-mediated tandem FriedeleCrafts reactions of
vinylidenecyclopropanes with acyl chlorides: a facile
synthetic method for the construction of 1-[2-(2,2-
diarylvinyl)-1-phenyl-3H-inden-5-yl]ethanone derivatives
*
Min Shi , Lei Wu, Jian-Mei Lu
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences,
354 Fenglin Lu, Shanghai 200032, China
Received 30 January 2008; received in revised form 1 February 2008; accepted 1 February 2008
Available online 7 February 2008
Abstract
AlCl3-mediated tandem FriedeleCrafts reaction of vinylidenecyclopropanes with acyl chlorides produced the corresponding 1-[2-(2,2-diaryl-
vinyl)-1-phenyl-3H-inden-5-yl]ethanone derivatives in moderate to good yields under mild conditions within short reaction time.
Ó 2008 Elsevier Ltd. All rights reserved.
Keywords: AlCl3; FriedeleCrafts reaction; Vinylidenecyclopropanes; Acyl chlorides; 1-[2-(2,2-Diarylvinyl)-1-phenyl-3H-inden-5-yl]ethanone derivatives;
Tandem reaction
1. Introduction
give an indene derivative via an intramolecular FriedeleCrafts
reaction.3a These results stimulated us to further explore the
transformation of VDCPs under mild conditions. Herein,
we wish to report an interesting AlCl3-mediated tandem inter-
molecular FriedeleCrafts reaction of VDCPs 1 with acyl
chlorides 2 that effectively produces 1-[2-(2,2-diarylvinyl)-1-
phenyl-3H-inden-5-yl]ethanone derivatives 3 in good to high
yields under mild conditions.4
Skeleton rearrangements of highly strained small rings with
multiple bonds and functional groups have attracted much
attention from both synthetic and mechanistic viewpoints.1
Among these interesting substances, vinylidenecyclopropanes
(VDCPs) are highly strained but readily accessible and stable
molecules that serve as useful building blocks in organic syn-
thesis.1 Thus far, it has been known that VDCPs can undergo
a variety of ring-opening/cycloaddition reactions upon heating
or photoirradiation as well as in the presence of Lewis acids
because the relief of ring strain can provide a powerful ther-
modynamic driving force.2,3 As an interesting example,
recently we have found a novel intramolecular rearrangement
of diarylvinylidenecyclopropanes having three substituents
at the 1- and 2-positions of the corresponding cyclopropane
catalyzed by Lewis acids to give 6aH-benzo[c]fluorine deriva-
tives via a double intramolecular FriedeleCrafts reaction or to
2. Results and discussion
Initial examinations using diphenylvinylidenecyclopropane
(1a, 0.2 mmol) having two phenyl groups at the 1-position and
acetyl chloride (2a, 0.16e0.3 mmol) as the substrates in the
presence of AlCl3 (0.1e0.3 mmol, 0.5e1.5 equiv) in 1,2-di-
chloroethane (DCE, 2.0 mL) were aimed at determining the
best conditions for this intermolecular FriedeleCrafts reaction
and the results of these experiments are summarized in Table
1. We found that using AlCl3 (1.0 equiv) as a Lewis acid,
1-[2-(2,2-diphenylvinyl)-1-phenyl-3H-inden-5-yl]ethanone 3a
was formed in 50% yield at room temperature (20 ꢀC) from
* Corresponding author. Tel.: þ86 21 54925137; fax: þ86 21 64166128.
E-mail address: mshi@mail.sioc.ac.cn (M. Shi).
0040-4020/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2008.02.003

3316
M. Shi et al. / Tetrahedron 64 (2008) 3315e3321
Table 1
Optimization of the reaction conditions
reaction conditions are to carry out the reaction in 2.0 mL
(or 1.0 mL) of DCM at room temperature using AlCl3
(0.2 mmol, 1.0 equiv) as a Lewis acid with 1a (0.2 mmol,
1.0 equiv) and 2a (0.2 mmol, 1.0 equiv). Under these optimal
conditions, these reactions generally completed within 5 min.
With these optimal reaction conditions identified, we next
carried out this interesting (1-phenyl-3H-inden-5-yl)ethanone
derivative forming reaction using a variety of starting mate-
rials 1 and 2. The results of these experiments are summarized
in Table 2. As can be seen from Table 2, the corresponding
(1-phenyl-3H-inden-5-yl)ethanone derivatives 3 were obtained
in 23e80% yields (Table 2, entries 1e11). Adding moderately
electron-donating substituents, such as a methyl group, on the
aromatic rings of 1 afforded the corresponding 1-[2-(2,2-di-p-
tolylvinyl)-1-phenyl-3H-inden-5-yl]ethanone 3d in 23% yield
(Table 2, entry 3). The reaction of VDCP 1d with benzoyl
chloride produced the corresponding product 3j in 80% yield
(Table 2, entry 9). When the reaction was carried out in
1.0 mL of DCM, the corresponding products were obtained
in slightly lower yields (the results shown in brackets). Product
structures were determined by 1H and 13C NMR spectroscopic
data, HRMS, microanalysis. Furthermore, the X-ray crystal
structures of 3a and 3e were determined and their CIF data
are presented in the Supplementary data (Figs. 1 and 2).5
Interestingly, introducing electron-withdrawing group,
such as a chloro or fluoro atom, on the aromatic ring of
R2 of VDCPs 1f and 1g furnished the corresponding indene
derivatives 4, (1-(4-{2-[6-chloro-3-(4-chlorophenyl)-1H-
inden-2-yl]-1-phenylvinyl}phenyl)-ethanone 4a and 1-(4-
{2-[6-fluoro-3-(4-fluorophenyl)-1H-inden-2-yl]-1-phenylvinyl}-
phenyl)-ethanone 4b, R¼Me), in moderate yields as mixtures of
E- and Z-isomers under the standard conditions (Table 3, entries 1
and 2). The crystal structure of trans-4a has been unambiguously
determinedbyX-raydiffraction(Fig. 3).6 Usingbenzoylchloride,
O
C Me
C6H5
C6H5
C6H5
1
C6H5
+
C6H5
C6H5
O
Lewis acid
.
Me C Cl
solvent, 5 min
C6H5
H
2
2a
1a
3a
Entrya Lewis acid
1a:2a Solvent
Temp (ꢀC) Yield of
3ab [%]
1
AlCl3 (1.0 equiv)
1:1.5 DCE
rt
44
26
2
AlCl3 (0.5 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.5 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.0 equiv)
AlCl3 (1.5 equiv)
AlCl3 (3.0 equiv)
ZnCl2 (1.0 equiv)
FeCl3 (1.0 equiv)
ZrCl4 (1.0 equiv)
1:1
1:1
1:1
DCE
DCE
DCE
rt
3
rt
50
Complex
16
4
rt
5
1:0.8 DCE
rt
6
1:1
1:1
1:1
1:1
1:1
1:1
1:1
1:1
1:1
1:1
1:1
DCE
DCE
DCE
CS2
ꢁ8
55
rt
Complex
Complex
Complexc
Complex
70
Trace
Complex
67
7
8
9
rt
10
11
12
13
14
15
16
17
18
19
20
21
22
23
a
DCM
THF
MeNO2
rt
rt
rt
Cl2CHCHCl2 rt
DCM
DCM
DCM
ꢁ8
53
ꢁ78
rt
Complex
61d
26
1:1.5 DCM
1:3.0 DCM
ꢁ78
rt
Complex
Trace
Trace
18
1:1
1:1
1:1
DCM
DCM
DCM
DCM
DCM
rt
rt
rt
Yb(OTf)3 (1.0 equiv) 1:1
Zr(OTf)4 (1.0 equiv) 1:1
rt
Trace
Trace
rt
All reactions were carried out using 1a (0.20 mmol), 2a (0.20 mmol), and
AlCl3 (0.20 mmol, 1.0 equiv) in solvent (2.0 mL) unless otherwise specified.
b
Isolated yields.
DBU (0.20 mmol) was added.
DCM: 1.0 mL was employed.
c
d
Table 2
AlCl3-mediated FriedeleCrafts reactions of 1 with 2 under these optimized
reaction conditions
the reaction of 1a (0.2 mmol) with 2a (0.2 mmol) (Table 1, en-
try 3). In the presence of excess amounts of AlCl3 (1.5 equiv),
complex product mixtures were obtained, although 26% of 3a
was formed using AlCl3 (0.5 equiv) as a Lewis acid (Table 1,
entries 2 and 4). Increasing and decreasing the amounts of 2a
did not improve the yields of 3a (Table 1, entries 1 and 5).
Raising and lowering the reaction temperatures, complex
product mixtures were formed (Table 1, entries 6 and 7). In
order to get rid of the in situ formed HCl, DBU was added
into the reaction system, but leading to the formation of com-
plex product mixtures (Table 1, entry 8). Examination of the
solvent effects revealed that dichloromethane (DCM) is the
solvent of choice to afford 3a in 70% yield at room tempera-
ture (Table 1, entries 9e13). Raising and lowering the reaction
temperatures as well as changing the ratios of reactants in
DCM did not improve the yield of 3a either (Table 1, entries
14e18). In higher concentration of the reaction solution
(1.0 mL of DCM), 3a was formed in 61% yield (Table 1, entry
16). Other Lewis acids such as ZnCl2, FeCl3, ZrCl4, Yb(OTf)3,
and Zr(OTf)4 are not as effective as AlCl3 under identical
conditions (Table 1, entries 17e21). Therefore, the best
O
C
R
R2
R2
R2
R3
R1
R1
R1
R1
O
1
AlCl3
R3
.
R C Cl
+
DCM, rt, 5 min
H
2
2
1
3
Entry
R1/R2/R3
R
Yield of 3a [%]
1
C6H5/C6H5/H, 1a
1a
Et
3b, 64 (44)b
3c, 46 (34)b
3d, 23
2
C6H5
Me
3
p-MeC6H4/C6H5/H, 1b
4
p-FC6H4/C6H5/H, 1c
1c
Me
C6H5
3e, 60 (50)b
3f, 70
3g, 64
5
6
1c
1c
p-MeOC6H4
p-ClC6H4
Me
7
3h, 61
8
p-ClC6H4/C6H5/H, 1d
1d
3i, 61 (42)b
3j, 80
3k, 50
9
C6H5
p-MeOC6H4
Me
10
11
a
1d
C6H5/C6H5/Me, 1e
3l, 77
Isolated yields.
DCM: 1.0 mL was employed.
b

M. Shi et al. / Tetrahedron 64 (2008) 3315e3321
3317
Table 3
AlCl3-mediated FriedeleCrafts reactions of 1 with 2 under these optimized
reaction conditions
R2'
R2
R2
O
C
1
R2
AlCl3
.
+
R
Cl
H
DCM, rt, 5 min
2
1
2
R
C
O
4
mixtures of cis- and trans-isomers
Entry
R2
R
Yield of 3 [%] (trans:cis)a
1
2
3
4
5
a
p-ClC6H4, 1f
p-FC6H4, 1g
1f
1f
1f
Me
Me
4a, 50 (9:1) [23 (9:1)]b
4b, 34 (5:1)
4c, 33 (40:1)
Figure 1. ORTEP drawing of 3a.
C6H5
p-ClC6H4
p-chlorobenzoyl chloride, and p-methoxybenzoyl chloride as
acyl reagents under identical conditions, similar results were ob-
tained (Table 3, entries 3e5).
4d, 32 (100:1)
4e, 35 (5:1)
p-CH3OC6H4
Isolated yields.
DCM: 1.0 mL was employed.
b
Since VDCP 1a can rearrange to the corresponding indene de-
rivative in the presence of Lewis acid,3 a control experiment of in-
dene 5a, derived from 1a in the presence of Yb(OTf)3, with acetyl
chloridewas carried out under thestandard conditions (Scheme1).
We found that the reaction became sluggish to give 3a in 50%
yieldafter24 h, suggestingthat the reactionof1with acylchloride
indeed can be accelerated by release of cyclopropyl ring strain
(27 kcal/mol)7 to provide a thermodynamic driving force and by
the p-character of the ring bonds of a cyclopropane affording
the kinetic opportunity to initiate the unleashing of the strain.8
On the basis of above results, a plausible mechanism for this
interesting AlCl3-mediated tandem FriedeleCrafts reaction is
tentatively outlined in Scheme 2 using 1a as a model. The
coordination of 1a with AlCl3 produces the initial zwitterionic
intermediate A, from which the corresponding cyclopropyl
ring-opened zwitterionic intermediate B is formed. Intramole-
cular FriedeleCrafts reaction with the aromatic group at the
C-1 position and the intermolecular FriedeleCrafts reaction
with the in situ generated acyl cation in the presence of AlCl3
take place at the same time to produce zwitterionic intermediate
C, which affords the corresponding zwitterionic intermediate D
via an allylic rearrangement. Subsequent twice 1,3-proton shift
along with the release of Lewis acid via zwitterionic intermedi-
ate E produces the corresponding indene derivative 3a. At the
present stage, we do not exactly understand which step is
responsible to the intermolecular FriedeleCrafts reaction
with acyl cation in the presence of AlCl3. We believe that the
ring-opening process provides a driving force to accelerate
Figure 2. ORTEP drawing of 3e.

3318
M. Shi et al. / Tetrahedron 64 (2008) 3315e3321
panes with acyl chlorides that produced the corresponding
1-[2-(2,2-diarylvinyl)-1-phenyl-3H-inden-5-yl]ethanonederiva-
tives in moderate to good yields under the optimized condi-
tions. Adding electron-withdrawing group on the aromatic
ring of R2 in VDCPs afforded another type of indene deriva-
tives 4 as mixtures of E- and Z-isomers in moderate yields
under mild conditions. Efforts are underway to further eluci-
date the reaction mechanism and to understand the scope and
limitations of this process.
3. Experimental section
3.1. General remarks
1H NMR spectra were recorded on a Varian Mercury vx
300 MHz spectrometer for solution in CDCl3 with tetrame-
thylsilane (TMS) as an internal standard; J values are in hertz.
Mass spectra were recorded with an HP-5989 instrument. Or-
ganic solvents used were dried by standard methods when nec-
essary. Part of solid compounds reported in this paper gave
satisfactory CHN microanalyses with a Carlo-Erba 1106 ana-
lyzer. X-ray diffraction analysis was performed on a Rigaku
AFC7R X-ray diffractometer. Commercially obtained reagents
were used without further purification. All reactions were
monitored by TLC with Huanghai GF254 silica gel coated
plates. Flash column chromatography was carried out using
300e400 mesh silica gel at increased pressure.
Figure 3. ORTEP drawing of 4a.
O
C
AlCl3
C6H5
C6H5
Me
Cl
3a
+
DCM, rt, 24 h
2a
H
5a
50% yield
Scheme 1. A control experiment.
3.2. General procedure for Lewis acid-catalyzed reaction
of arylvinylidenecyclopropanes with acyl chlorides
the intermolecular FriedeleCrafts reaction. This is why these
transformations complete within shorter reaction time.
In conclusion, we have identified an interesting AlCl3-me-
diated tandem FriedeleCrafts reaction of vinylidenecyclopro-
Under an argon atmosphere, arylvinylidenecyclopropane 1
(0.2 mmol) and AlCl3 (0.2 mmol) were added into a Schlenk
tube, and then the solvent CH2Cl2 (1.0 mL) was added. The
1
AlCl3
+
.
1
.
1a
+
2
2
AlCl3
AlCl3
-
A
-
B
1
1
2
+
+
R C O
+
.
.
2
R
R
Intramolecular and
intermolecular
Friedel-Crafts
C
O
C
O
AlCl3
-
D
H
AlCl3
-
C
H
H
1
2
1,3-H shift
- AlCl3
1,3-H shift
+
.
3a
R
C
O
AlCl3
-
E
Scheme 2. A plausible reaction mechanism.

M. Shi et al. / Tetrahedron 64 (2008) 3315e3321
3319
reaction mixture was stirred at room temperature for a while,
then acyl chloride 2 (0.2 mmol) was added. The reaction was
quenched after 5 min by addition of water. Then the solvent
was removed under reduced pressure and the residue was pu-
rified by flash column chromatography.
133.9, 134.5, 137.5, 137.6, 139.8, 143.3, 143.7, 143.9, 144.9,
149.6, 198.1. IR (CH2Cl2) n 3023, 2923, 2853, 1731, 1676,
1604, 1508, 1428, 1356, 1257, 1172, 820, 703, 527 cmꢁ1. MS
(%) m/e 440 (Mþ, 100), 397 (11), 347 (12), 305 (21), 289 (9).
HRMS (EI) calcd for C33H28O: 440.2140. Found: 440.2140.
1
Compound 3e. A yellow solid, mp: 216e219 ꢀC. H NMR
3.3. Analytical data of the products
(CDCl3, 300 MHz, TMS) d 2.57 (s, 3H, CH3), 3.01 (s, 2H,
CH2), 6.90e6.95 (m, 2H, Ar), 7.03 (s, 1H), 7.10e7.21 (m,
4H, Ar), 7.25e7.33 (m, 3H, Ar), 7.41e7.55 (m, 5H, Ar),
7.83e7.86 (m, 2H, Ar). 13C NMR (CDCl3, 75 MHz, TMS)
1
Compound 3a. A yellow solid, mp: 182e184 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 2.55 (s, 3H, CH3), 3.00 (s, 2H,
CH2), 7.13 (s, 1H), 7.21e7.23 (m, 5H, Ar), 7.30e7.32 (m,
3H, Ar), 7.46e7.52 (m, 8H, Ar), 7.77e7.83 (m, 2H, Ar).
13C NMR (CDCl3, 75 MHz, TMS) d 26.6, 39.7, 119.7,
122.5, 123.1, 127.2, 127.3, 127.5, 127.9, 128.2, 128.6,
128.7, 129.7, 130.1, 134.0, 134.4, 140.6, 142.2, 143.2,
143.6, 144.3, 149.4, 197.9. IR (CH2Cl2) n 3076, 3056, 3026,
2924, 1676, 1599, 1492, 1443, 1356, 1256, 1161, 1074, 944,
765, 702 cmꢁ1. MS (%) m/e 412 (Mþ, 14), 335 (13), 313
(10), 285 (12), 169 (62), 147 (38), 119 (35), 105 (16), 97
(22), 77 (15), 69 (100), 57 (12), 55 (15), 51 (18), 44 (73),
43 (42). Anal. Calcd for C31H24O requires C, 90.26%; H,
5.86%. Found: C, 90.22%; H, 5.88%.
d 26.7, 39.8, 115.2 (d, JCeF¼21.8 Hz), 115.9 (d, JCeF
¼
21.2 Hz), 119.9, 122.9, 123.3, 127.4, 128.0, 128.7, 128.8 (d,
JCeF¼8.0 Hz), 129.6, 131.8 (d, JCeF¼8.0 Hz), 134.3, 136.4
(d, JCeF¼2.9 Hz), 138.4 (d, JCeF¼2.9 Hz), 141.4, 143.0,
143.7, 144.9, 149.3, 162.4 (d, JCeF¼247.2 Hz), 162.6 (d,
JCeF¼246.6 Hz), 197.9. IR (CH2Cl2) n 3052, 1673, 1608,
1505, 1428, 1355, 1280, 1254, 1221, 1159, 1125, 973, 944,
911, 832, 819, 705, 651, 566, 507, 483 cmꢁ1. MS (%) m/e
448 (Mþ, 100), 433 (12), 405 (12), 327 (30), 309 (38), 307
(16), 109 (10), 91 (7), 69 (8), 43 (71). HRMS (EI) calcd for
C31H22F2O: 448.1639. Found: 448.1639.
Compound 3f. A yellow solid, mp: 194e196 ꢀC. 1H
NMR (CDCl3, 300 MHz, TMS) d 3.03 (s, 2H, CH2), 6.89e
6.94 (m, 2H, Ar), 7.05 (s, 1H), 7.10e7.18 (m, 4H, Ar), 7.23e
7.29 (m, 2H, Ar), 7.33e7.36 (m, 1H, Ar), 7.42e7.57 (m, 8H,
Ar), 7.69e7.76 (m, 4H, Ar). 13C NMR (CDCl3, 75 MHz,
1
Compound 3b. A yellow solid, mp: 161e163 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 1.19 (t, J¼7.5 Hz, 3H, CH3), 2.94
(q, J¼7.5 Hz, 2H, CH2), 3.00 (s, 2H, CH2), 7.13 (s, 1H),
7.19e7.24 (m, 5H, Ar), 7.30e7.32 (m, 3H, Ar), 7.42e7.54
(m, 8H, Ar), 7.78e7.85 (m, 2H, Ar). 13C NMR (CDCl3,
75 MHz, TMS) d 8.5, 31.7, 39.7, 119.8, 122.6, 122.8, 126.9,
127.2, 127.5, 127.9, 128.2, 128.6, 128.7, 129.7, 130.1, 133.8,
134.4, 140.7, 142.2, 143.2, 143.6, 144.2, 144.4, 149.2, 200.6.
IR (CH2Cl2) n 3056, 3027, 2934, 1678, 1599, 1492, 1444,
TMS) d 39.8, 115.1 (d, JCeF¼21.6 Hz), 115.9 (d, JCeF
¼
21.3 Hz), 119.7, 122.9, 125.2, 128.2 (d, JCeF¼8.1 Hz), 128.7,
128.8 (d, JCeF¼8.0 Hz), 129.4, 129.7, 129.8, 131.7, 131.9,
132.0, 134.3, 134.5, 136.3 (d, JCeF¼3.0 Hz), 138.2, 138.4 (d,
JCeF¼2.7 Hz), 141.3, 142.8, 143.5, 144.9, 148.9, 162.3 (d,
JCeF¼246.9 Hz), 162.5 (d, JCeF¼246.2 Hz), 196.6. IR
(CH2Cl2) n 3058, 2925, 1652, 1605, 1507, 1233, 1159, 836,
704, 567 cmꢁ1. MS (%) m/e 510 (Mþ, 65), 309 (13), 169
(31), 147 (16), 119 (23), 105 (100), 97 (16), 91 (9), 77 (30),
69 (47), 57 (12), 51 (11), 47 (10), 44 (34), 43 (17). HRMS
(EI) calcd for C36H24F2O: 510.1795. Found: 510.1789.
1376, 1228, 1153, 1075, 1110, 944, 802, 765, 702, 588 cmꢁ1
.
MS (%) m/e 426 (Mþ, 100), 397 (61), 369 (12), 291 (53),
289 (31), 276 (14), 165 (14), 145 (19), 91 (18), 57 (39).
Anal. Calcd for C32H26O requires C, 90.11%; H, 6.14%.
Found: C, 90.28%; H, 6.32%.
1
Compound 3c. A yellow solid, mp: 138e139 ꢀC. H NMR
1
(CDCl3, 300 MHz, TMS) d 3.02 (s, 2H, CH2), 7.14 (s, 1H, Ar),
7.19e7.25 (m, 5H, Ar), 7.30e7.35 (m, 3H, Ar), 7.42e7.56 (m,
11H, Ar), 7.66e7.76 (m, 4H, Ar). 13C NMR (CDCl3, 75 MHz,
TMS) d 39.8, 119.6, 122.6, 125.1, 127.3, 127.6, 128.0, 128.1,
128.2, 128.6, 128.8, 129.4, 129.77, 129.83, 130.2, 131.9,
134.3, 134.5, 138.4, 140.7, 142.3, 143.1, 143.6, 144.2,
144.5, 149.1, 196.7. IR (CH2Cl2) n 3056, 3026, 2911, 1652,
1599, 1277, 1102, 769, 701 cmꢁ1. MS (%) m/e 474 (Mþ,
40), 346 (15), 335 (10), 291 (18), 169 (44), 147 (27), 119
(22), 105 (100), 97 (19), 91 (19), 77 (55), 69 (59), 57 (29),
55 (30), 51 (19), 44 (29), 43 (66). Anal. Calcd for C36H26O
requires C, 91.11%; H, 5.52%. Found: C, 90.81%; H, 5.76%.
Compound 3g. A yellow solid, mp: 195e197 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 3.03 (s, 2H, CH2), 3.86 (s, 3H,
CH3), 6.89e6.96 (m, 4H, Ar), 7.05 (s, 1H, CH), 7.11e7.19 (m,
4H, Ar), 7.24e7.35 (m, 3H, Ar), 7.42e7.53 (m, 5H, Ar),
7.66e7.67 (m, 2H, Ar), 7.76e7.79 (m, 2H, Ar). 13C NMR
(CDCl3, 75 MHz, TMS) d 39.8, 55.4, 113.4, 115.1 (d, JCeF
¼
21.2 Hz), 115.9 (d, JCeF¼21.2 Hz), 119.6, 123.0, 124.9, 128.0,
128.7, 128.8 (d, JCeF¼8.0 Hz), 129.0, 129.7, 130.7, 131.8 (d,
JCeF¼8.0 Hz), 132.3, 134.4, 135.2, 136.4 (d, JCeF¼3.4 Hz),
138.4 (d, JCeF¼2.9 Hz), 141.1, 142.7, 143.1, 145.0, 148.4,
162.4 (d, JCeF¼247.3 Hz), 162.5 (d, JCeF¼246.2 Hz), 162.8,
195.4. IR (CH2Cl2) n 3052, 2926, 1647, 1601, 1508, 1255,
1167, 836, 777, 703, 566 cmꢁ1. MS (%) m/e 540 (Mþ, 27),
335 (14), 313 (13), 285 (10), 169 (72), 147 (33), 135 (46), 119
(35), 105 (18), 97 (23), 91 (14), 77 (25), 69 (100), 57 (19), 55
(23), 51 (20), 44 (51), 43 (30). Anal. Calcd for C37H26F2O2
requires C, 82.20%; H, 4.85%. Found: C, 82.10%; H, 4.88%.
1
Compound 3d. A yellow solid, mp: 182e185 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 2.30 (s, 3H, CH3), 2.48 (s, 3H,
CH3), 2.57 (s, 3H, CH3), 3.03 (s, 2H, CH2), 7.07 (d, 2H,
J¼7.8 Hz, Ar), 7.18 (d, 2H, J¼7.8 Hz, Ar), 7.27 (d, 2H,
J¼8.4 Hz, Ar), 7.30e7.52 (m, 7H, Ar), 7.50 (s, 1H), 7.51 (s,
1H, Ar), 7.82 (d, 2H, J¼8.4 Hz, Ar). 13C NMR (CDCl3,
75 MHz, TMS) d 21.1, 21.4, 26.7, 39.8, 119.6, 121.7, 123.1,
125.7, 127.2, 127.4, 127.8, 128.6, 128.9, 129.4, 129.7, 130.0,
1
Compound 3h. A yellow solid, mp: 169e170 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 3.03 (s, 2H, CH2), 6.89e6.95 (m,
2H, Ar), 7.05 (s, 1H, CH), 7.11e7.20 (m, 4H, Ar), 7.25e7.36

3320
M. Shi et al. / Tetrahedron 64 (2008) 3315e3321
(m, 3H, Ar), 7.41e7.53 (m, 7H, Ar), 7.66e7.71 (m, 4H, Ar).
13C NMR (CDCl3, 75 MHz, TMS) d 39.8, 115.2 (d, JCeF
21.7 Hz), 116.0 (d, JCeF¼21.1 Hz), 119.8, 122.9, 125.0,
128.1, 128.5, 128.7, 128.9 (d, JCeF¼8.0 Hz), 129.3, 129.6,
128.2, 128.5, 129.6, 131.1, 134.2, 134.3, 140.3, 142.2,
142.8, 145.3, 148.2, 149.1, 150.7, 198.1. IR (CH2Cl2)
n 3056, 3026, 2965, 2927, 1676, 1605, 1492, 1443, 1423,
1355, 1253, 1164, 1075, 943, 828, 775, 700, 656 cmꢁ1. MS
(%) m/e 426 (Mþ, 100), 411 (15), 383 (9), 333 (15), 305
(28), 291 (15), 289 (13). HRMS (EI) calcd for C32H26O:
426.1984. Found: 426.1984.
¼
131.2, 131.8 (d, JCeF¼8.4 Hz), 134.1, 134.2, 136.3 (d, JCeF
¼
3.4 Hz), 136.5, 138.4, 141.5, 142.9, 143.7, 144.9, 149.1,
162.4 (d, JCeF¼251.8 Hz), 162.7 (d, JCeF¼253.3 Hz), 195.3.
IR (CH2Cl2) n 3056, 2925, 1654, 1606, 1508, 1234, 1159,
835, 737, 704, 566 cmꢁ1. MS (%) m/e 544 (Mþ, 12), 335
(14), 169 (60), 147 (33), 131 (11), 119 (42), 105 (23), 100
(17), 97 (22), 91 (13), 77 (24), 69 (100), 55 (24), 51 (21), 44
(79), 43 (25). Anal. Calcd for C36H23ClF2O requires C,
79.34%; H, 4.25%. Found: C, 79.34%; H, 4.32%.
Compound 4a. Ayellow solid, mp: 189e192 ꢀC. (E-isomer)
1H NMR (CDCl3, 300 MHz, TMS) d 2.55 (s, 3H, CH3), 2.93 (s,
2H), 7.11e7.19(m, 4H, Ar), 7.24e7.30 (m, 4H, Ar), 7.41(d, 2H,
J¼8.4 Hz, Ar), 7.40e7.51 (m, 5H, Ar), 7.83 (d, 2H, J¼8.4 Hz,
1
Ar). (Z-isomer) H NMR (CDCl3, 300 MHz, TMS) d 2.70 (s,
3H, CH3), 2.93 (s, 2H), 7.11e7.19 (m, 4H, Ar), 7.24e7.30 (m,
4H, Ar), 7.40e7.51 (m, 7H, Ar), 8.06 (d, 2H, J¼8.4 Hz, Ar).
13C NMR (CDCl3, 75 MHz, TMS) d 26.6, 39.4, 120.9, 124.0,
124.3, 126.6, 127.1, 128.2, 128.3, 129.0, 130.1, 131.0, 131.8,
132.8, 134.0, 135.6, 140.0, 140.6, 141.5, 142.6, 144.3, 144.9,
146.8, 197.5. IR (CH2Cl2) n 3052, 2924, 2852, 1682, 1602,
1564, 1357, 1266, 1165, 1091, 939, 825, 736 cmꢁ1. MS (%)
m/e 480 (Mþ, 48), 325 (34), 289 (22), 69 (12), 43 (100).
HRMS (EI) calcd for C31H22Cl2O: 480.1048. Found: 480.1048.
Compound 4b. A yellow solid, mp: 216e218 ꢀC. (E-isomer)
1H NMR (CDCl3, 300 MHz, TMS) d 2.54 (s, 3H, CH3), 2.93 (s,
2H, CH2), 6.92 (d, 2H, J¼9.3 Hz, Ar), 7.04e7.31 (m, 8H, Ar),
7.42e7.49 (m, 5H, Ar), 7.82 (d, 2H, J¼8.7 Hz, Ar). (Z-isomer)
1H NMR (CDCl3, 300 MHz, TMS) d 2.70 (s, 3H, CH3), 2.93 (s,
2H, CH2), 6.87 (d, 2H, J¼9.4 Hz, Ar), 7.04e7.31 (m, 8H, Ar),
7.42e7.49 (m, 5H, Ar), 8.06 (d, 2H, J¼8.4 Hz, Ar). 13C NMR
(CDCl3, 75 MHz, TMS) d 26.5, 39.5, 111.2 (d, J¼23.0 Hz),
113.4 (d, J¼23.0 Hz), 115.7 (d, J¼21.2 Hz), 120.9 (d,
J¼9.2 Hz), 124.6, 127.0, 127.1, 127.6, 128.1, 128.3, 128.7,
128.9, 130.2, 130.6 (d, J¼10.8 Hz), 131.4 (d, J¼8.0 Hz),
135.5, 139.9 (d, J¼30.4 Hz), 140.1 (d, J¼42.9 Hz), 140.7,
144.6, 145.4, 145.5, 147.0, 161.9 (d, J¼243.1 Hz), 162.4 (d,
J¼246.6 Hz), 197.4. IR (CH2Cl2) n 3052, 2919, 1683, 1603,
1268, 1095, 956, 838, 702, 550 cmꢁ1. MS (%) m/e 448 (Mþ,
8), 335 (13), 313 (15), 169 (56), 147 (29), 119 (33), 97 (23),
69 (100), 51 (16), 50 (14), 44 (38), 43 (21). Anal. Calcd for
C31H22F2O requires C, 83.02; H, 4.94%. Found: C, 83.05%;
H, 5.00%.
1
Compound 3i. A yellow solid, mp: 214e217 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 2.48 (s, 3H, CH3), 2.94 (s, 2H,
CH2), 6.96e7.00 (m, 3H, Ar), 7.08e7.15 (m, 4H, Ar), 7.24
(d, J¼8.4 Hz, Ar), 7.35e7.43 (m, 7H, Ar), 7.74e7.76 (m, 2H,
Ar). 13C NMR (CDCl3, 75 MHz, TMS) d 26.7, 39.8, 120.0,
123.3, 123.5, 127.4, 128.1, 128.4, 128.7, 129.2, 129.6, 131.5,
133.6, 134.1, 134.2, 134.4, 138.6, 140.4, 140.9, 143.0, 143.3,
145.4, 149.1, 197.9. IR (CH2Cl2) n 3055, 2919, 1713, 1676,
1606, 1491, 1356, 1258, 1090, 1014, 829, 703, 528 cmꢁ1. MS
(%) m/e 480 (Mþ, 17), 335 (12), 169 (43), 149 (27), 147 (17),
119 (26), 97 (29), 91 (15), 86 (21), 71 (27), 69 (100), 57 (41),
51 (29), 49 (42), 44 (52), 43 (63). Anal. Calcd for C31H22Cl2O
requires C, 77.34%; H, 4.61%. Found: C, 77.58%; H, 4.80%.
1
Compound 3j. A yellow solid, mp: 201e204 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 3.06 (s, 2H, CH2), 7.06e7.09 (m,
3H, Ar), 7.18e7.25 (m, 4H, Ar), 7.35 (d, 1H, J¼8.1 Hz, Ar),
7.43e7.59 (m, 10H, Ar), 7.70e7.77 (m, 4H, Ar). 13C NMR
(CDCl3, 75 MHz, TMS) d 39.8, 119.9, 123.5, 125.2, 128.2,
128.4, 128.7, 129.2, 129.4, 129.7, 129.8, 131.5, 132.0, 133.6,
134.2, 134.6, 138.2, 138.6, 140.5, 140.8, 142.8, 143.1, 145.5,
148.7, 196.6. IR (CH2Cl2) n 3057, 2924, 1652, 1606, 1491,
1280, 1101, 1014, 829, 709 cmꢁ1. MS (%) m/e 543 (Mꢁ1þ,
41), 289 (13), 105 (100), 77 (36). Anal. Calcd for C36H24Cl2O
requires C, 79.57%; H, 4.45%. Found: C, 79.41%; H, 4.40%.
1
Compound 3k. A yellow solid, mp: 182e185 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 3.06 (s, 2H, CH2), 3.86 (s, 3H,
CH3), 6.94 (d, 2H, J¼8.7 Hz, Ar), 7.07 (d, 3H, J¼8.4 Hz,
Ar), 7.18e7.24 (m, 4H, Ar), 7.35 (d, 2H, J¼8.7 Hz, Ar),
7.43e7.53 (m, 7H, Ar), 7.65e7.67 (m, 2H, Ar), 7.78 (d, 2H,
J¼9.0 Hz, Ar). 13C NMR (CDCl3, 75 MHz, TMS) d 39.8,
55.4, 113.4, 119.8, 123.6, 125.0, 128.1, 128.4, 128.7, 129.0,
129.1, 129.7, 130.6, 131.5, 132.3, 133.5, 134.1, 134.2, 135.3,
138.7, 140.5, 140.6, 142.7, 142.8, 145.5, 148.2, 162.8, 195.4.
IR (CH2Cl2) n 3059, 2919, 1647, 1601, 1508, 1491, 1255,
1167, 830, 777, 702 cmꢁ1. MS (%) m/e 574 (Mþ, 14), 572
(23), 289 (8), 135 (100), 107 (13), 85 (12), 77 (20), 71 (16),
57 (23), 43 (14). Anal. Calcd for C37H26Cl2O2 requires C,
77.49%; H, 4.57%. Found: C, 79.20%; H, 4.69%.
Compound 4c. Ayellow solid, mp: 152e155 ꢀC. (E-isomer)
1H NMR (CDCl3, 300 MHz, TMS) d 2.94 (s, 2H, CH2), 7.14e
7.20 (m, 4H, Ar), 7.25e7.32 (m, 4H, Ar), 7.41e7.59 (m, 10H,
1
Ar), 7.69e7.79 (m, 4H, Ar). (Z-isomer) H NMR (CDCl3,
300 MHz, TMS) d 3.00 (s, 2H, CH2), 7.14e7.20 (m, 4H, Ar),
7.25e7.32 (m, 4H, Ar), 7.41e7.59 (m, 10H, Ar), 7.88e7.94
(m, 4H, Ar). 13C NMR (CDCl3, 75 MHz, TMS) d 39.4, 120.9,
124.0, 124.2, 126.6, 126.8, 128.2, 129.0, 129.9, 130.17,
130.21, 131.0, 131.8, 132.3, 132.9, 134.0, 136.0, 137.6, 140.0,
140.7, 141.6, 142.6, 144.2, 144.9, 146.2, 196.0. IR (CH2Cl2)
n 3057, 2925, 1658, 1599, 1577, 1481, 1445, 1315, 1276,
1140, 1091, 938, 829, 700, 534 cmꢁ1. MS (%) m/e 542 (Mþ,
100), 402 (7), 327 (11), 325 (28), 289 (16), 105 (67), 77 (15).
HRMS (EI) calcd for C36H24Cl2O: 542.1204. Found: 542.1204.
Compound 4d. Ayellow solid, mp: 218e221 ꢀC. (E-isomer)
1H NMR (CDCl3, 300 MHz, TMS) d 2.94 (s, 2H, CH2), 7.13e
7.21 (m, 4H, Ar), 7.26e7.32 (m, 5H, Ar), 7.41e7.52 (m, 9H,
1
Compound 3l. A yellow solid, mp: 110e112 ꢀC. H NMR
(CDCl3, 300 MHz, TMS) d 1.09 (d, 3H, J¼7.5 Hz, CH3),
2.57 (s, 3H, CH3), 3.12 (q, 1H, J¼7.5 Hz), 6.81 (d, 1H,
J¼1.2 Hz), 7.24e7.52 (m, 16H, Ar), 7.81e7.85 (m, 2H, Ar).
13C NMR (CDCl3, 75 MHz, TMS) d 17.3, 26.7, 43.9, 119.8,
122.3, 122.4, 127.6, 127.76, 127.84, 127.9, 128.0, 128.1,

M. Shi et al. / Tetrahedron 64 (2008) 3315e3321
3321
Ar), 7.66e7.74 (m, 4H, Ar). 13C NMR (CDCl3, 75 MHz, TMS)
References and notes
d 39.4, 120.9, 124.0, 124.4, 126.7, 126.9, 128.2, 128.6, 129.0,
130.1, 130.2, 131.0, 131.3, 131.82, 131.85, 132.8, 134.0,
135.6, 135.9, 138.7, 139.9, 140.6, 141.5, 142.6, 144.4, 145.0,
146.5, 194.7. IR (CH2Cl2) n 2955, 2925, 2854, 1714, 1660,
1600, 1486, 1455, 1274, 1091, 1017, 927, 858, 830,
762 cmꢁ1. MS (%) m/e 578 (Mþ, 10), 325 (6), 139 (24), 111
(8), 91 (8), 77 (8), 69 (11), 55 (8), 44 (100), 43 (21). Anal. Calcd
for C36H23Cl3O requires C, 74.82%; H, 4.01%. Found: C,
74.55%; H, 4.18%.
Compound 4e. A yellow solid, mp: 117e120 ꢀC. (E-isomer)
1H NMR (CDCl3, 300 MHz, TMS) d 2.94 (s, 2H, CH2), 3.88 (s,
3H, OCH3), 6.95 (d, 2H, J¼8.4 Hz, Ar), 7.12e7.20 (m, 5H, Ar),
7.20e7.33 (m, 4H, Ar), 7.41e7.52 (m, 6H, Ar), 7.66 (d, 2H,
J¼8.4 Hz, Ar), 7.81 (d, 2H, J¼8.4 Hz, Ar). (Z-isomer) 1H
NMR (CDCl3, 300 MHz, TMS) d 3.01 (s, 2H, CH2), 3.92 (s,
3H, OCH3), 7.03 (d, 2H, J¼8.4 Hz, Ar), 7.12e7.33 (m, 9H,
Ar), 7.41e7.52 (m, 6H, Ar), 7.90 (d, 2H, J¼8.4 Hz, Ar), 7.92
(d, 2H, J¼8.4 Hz, Ar). 13C NMR (CDCl3, 75 MHz, TMS)
d 39.4, 55.5, 113.5, 113.7, 120.8, 124.0, 126.7, 126.8, 127.2,
127.8, 128.2, 128.4, 129.0, 129.9, 130.2, 131.0, 131.7, 132.4,
132.5, 132.9, 133.9, 136.8, 140.1, 140.7, 141.8, 144.9, 145.8,
163.1, 199.4. IR (CH2Cl2) n 3056, 3030, 2956, 2926, 2853,
1727, 1650, 1601, 1509, 1481, 1461, 1418, 1313, 1281, 1256,
1171, 1152, 1091, 928, 853, 832, 771, 700, 621, 594,
534 cmꢁ1. MS (%) m/e 572 (Mþ, 29), 572 (29), 289 (10), 136
(8), 135 (100), 77 (21), 44 (57). HRMS (EI) calcd for
C37H26Cl2O2: 572.1310. Found: 572.1310.
1. (a) For recent review, see: Maeda, H.; Mizuno, K. J. Synth. Org. Chem.
Jpn. 2004, 62, 1014e1025; For the synthesis of vinylidenecyclopro-
panes, see: (b) Isagawa, K.; Mizuno, K.; Sugita, H.; Otsuji, Y. J. Chem.
Soc., Perkin Trans. 1 1991, 2283e2285 and references therein; (c)
Al-Dulayymi, J. R.; Baird, M. S. J. Chem. Soc., Perkin Trans. 1 1994,
1547e1548.
2. Selected recent articles about VDCPs: (a) Maeda, H.; Hirai, T.; Sugimoto,
A.; Mizuno, K. J. Org. Chem. 2003, 68, 7700e7706; (b) Pasto, D. J.;
Brophy, J. E. J. Org. Chem. 1991, 56, 4554e4556; (c) Sugita, H.; Mizuno,
K.; Saito, T.; Isagawa, K.; Otsuji, Y. Tetrahedron Lett. 1992, 33, 2539e
2542; (d) Mizuno, K.; Sugita, H.; Kamada, T.; Otsuji, Y. Chem. Lett.
1994, 449e452 and references therein.
3. For recent contributions from our group on the Lewis acid-catalyzed trans-
formation, see: (a) Xu, G.-C.; Liu, L.-P.; Lu, J.-M.; Shi, M. J. Am. Chem.
Soc. 2005, 127, 14552e14553; (b) Xu, G.-C.; Ma, M.; Liu, L.-P.; Shi,
M. Synlett 2005, 1869e1872; (c) Zhang, Y.-P.; Lu, J.-M.; Xu, G.-C.; Shi,
M. J. Org. Chem. 2007, 72, 509e516; (d) Lu, J.-M.; Shi, M. Org. Lett.
2007, 9, 1805e1808.
4. (a) For a review, see: Fleming, I. Chemtracts: Org. Chem. 2001, 14, 405e
406; (b) For the reaction of methylenecyclopropanes with acyl chloride in
the presence of AlCl3, see: Huang, X.; Yang, Y.-W. Org. Lett. 2007, 9,
1667e1670.
5. The crystal data of 3a have been deposited in CCDC with number 664633.
Empirical formula: C32H26O; formula weight: 426.53; crystal color, habit:
colorless, prismatic; crystal system: monoclinic; lattice type: primitive; laꢀt-
˚
˚
˚
tice parameters: a¼9.661(5) A, b¼10.626(5) A, c¼22.961(11) A, a¼90 ,
3
b¼95.370(9)ꢀ, g¼90ꢀ, V¼2347(2) A ; space group: P2(1)/n; Z¼4;
˚
Dcalcd¼1.207 g/cm3; F000¼904; diffractometer: Rigaku AFC7R; residuals:
R; Rw: 0.0583, 0.1247.
The crystal data of 3e have been deposited in CCDC with number 665675.
Empirical formula: C31H22F2O; formula weight: 448.49; crystal color,
habit: colorless, prismatic; crystal system: monoclinic; lattice type: primi-
˚
˚
3
tive; lattice parameters: a¼8.0477(8) A, b¼28.566(3) A, c¼
Acknowledgements
ꢀ
ꢀ
ꢀ
˚
˚
10.6859(10) A, a¼90 , b¼111.070(2) , g¼90 , V¼2292.3(4) A ; space
group: P2(1)/c; Z¼4; Dcalcd¼1.300 g/cm3; F000¼936; diffractometer:
Rigaku AFC7R; residuals: R; Rw: 0.0534, 0.1149.
Financial support from the Shanghai Municipal Committee
of Science and Technology (04JC14083, 06XD14005) and the
National Natural Science Foundation of China (20472096,
203900502, 20672127, and 20732008) is greatly
acknowledged.
6. The X-ray crystal data of 4a have been deposited in CCDC with number
663279. Empirical formula: C31H22Cl2O; formula weight: 481.39; crystal
color, habit: colorless, prismatic; crystal system: monoclinic; lattice type:
˚
˚
primitive; lattice parameters: a¼22.321(2) A, b¼15.0593(14) A,
3
ꢀ
ꢀ
ꢀ
˚
˚
c¼7.3913(7) A, a¼90 , b¼97.347(2) , g¼90 , V¼2464.1(4) A ; space
group: P2(1)/c; Z¼4; Dcalcd¼1.298 g/cm3; F000¼1000; diffractometer:
Rigaku AFC7R; residuals: R; Rw: 0.0526, 0.1125.
Supplementary data
7. Lukina, M. Y. Russ. Chem. Rev. 1963, 32, 635e647.
8. (a) de Meijere, A. Top. Curr. Chem. 1988, V144; (b) Strain and its Impli-
cations in Organic Chemistry; de Meijere, A., Blechert, S., Eds.; NATO
ASI series; Kluwer Academic: Dordrecht, Boston, London, 1989.
Supplementary data associated with this article can be
found in the online version, at doi:10.1016/j.tet.2008.02.003.