Diastereoselective nucleophilic cyclopropanation of 1,2-diketones and α-ketoimines with bis(iodozincio)methane

Article abstract of DOI:10.3987/COM-08-S(N)104

A reaction of 1,2-diketones and α-ketoimines with bis(iodozincio)methane gave cyclopropan-1,2-diol and 2-aminocyclopropanol respectively via nucleophilic [2+1]cycloaddition. The reaction proceeded via a sequential nucleophilic attack of the dizinc reagent to vicinal two carbonyl group. The reaction showed high diastereoselectivity to give cis-isomer via a face-to-face coordination between the substrate and bis(iodozincio)methane.

Full text of DOI:10.3987/COM-08-S(N)104

HETEROCYCLES, Vol. 76, No. 2, 2008
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HETEROCYCLES, Vol. 76, No. 2, 2008, pp. 1381 - 1399. © The Japan Institute of Heterocyclic Chemistry
Received, 15th April, 2008, Accepted, 19th May, 2008, Published online, 26th May, 2008. COM-08-S(N)104
DIASTEREOSELECTIVE NUCLEOPHILIC CYCLOPROPANATION OF
1,2-DIKETONES AND α-KETOIMINES WITH
BIS(IODOZINCIO)METHANE
Kenichi Nomura, Keisuke Asano, Takuya Kurahashi, and Seijiro
Matsubara*
Department of Material Chemistry, Graduate School of Engineering, Kyoto
University, Kyoutodaigaku-katsura, Nishikyo-ku, Kyoto 615-8510, Japan;
E-Mail: matsubar@orgrxn.mbox.media.kyoto-u.ac.jp
This paper is dedicated to Professor Dr. Ryoji Noyori as we celebrate his 70th
birthday.
Abstract
–
A
reaction of 1,2-diketones and α-ketoimines with
bis(iodozincio)methane gave cyclopropan-1,2-diol and 2-aminocyclopropanol
respectively via nucleophilic [2+1]cycloaddition. The reaction proceeded via a
sequential nucleophilic attack of the dizinc reagent to vicinal two carbonyl group.
The reaction showed high diastereoselectivity to give cis-isomer via a face-to-face
coordination between the substrate and bis(iodozincio)methane.
INTRODUCTION
Cyclopropane-skeletons have been found in many natural products, and also used as versatile synthetic
intermediates.1
The most famous cyclopropanation is Simmons-Smith reaction: Zinc carbenoid
reacts with alkenes electrophilically to give a three-membered ring.2 The zinc carbenoid can be
prepared easily from diiodomethane and zinc-copper couple in diethyl ether. Meanwhile, when
diiodomethane was treated with zinc in the presence of catalytic amount of lead in THF, the
Simmons-Smith reagent is not obtained. In this condition, the further reduction of the reagent proceeds
to give bis(iodozincio)methane (1).3 This dizinc reagent, which possess a couple of zinc atoms on a
carbon, works as a dianion equivalent.4,5 The reagent has an ability to form a couple of C-C bond on the
same carbon, so treatment of this reagent with the substrate, carrying two electrophilic group vicinally,

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HETEROCYCLES, Vol. 76, No. 2, 2008
such as 1,2-diketones may arise [2+1]cycloaddition. This nucleophilic cycloaddition would afford
cyclopropan-1,2-diol.
In fact, treatment of benzil (2a) with bis(iodozincio)methane (1) gave cis-1,2-diphenyl-
cyclopropane-1,2-diol in good yield.6 It is notable that treatment of a simple ketone with the reagent did
not proceed satisfactorily. For example, treatment of acetophenone with the dizinc at room temperature
resulted in the complete recovery of the starting material.7 The reason why the reaction with benzil
proceed smoothly is that a double coordination with the substrate enhances the reactivity of the dizinc
reagent. Such activation was also observed in the reaction of Grignard reagent and α-alkoxyketones via
Cram’s chelation.8 The reaction of benzil and dizinc proceeded with high diastereoselectivity. We
investigated the scope and limitation of this nucleophilic [2+1]cycloaddition.
RESULTS AND DISCUSSION
o
Benzil (2a) was treated with bis(iodozincio)methane (1) at 25 C in THF for 0.5 h. Acetic anhydride
was added to the reaction mixture to convert the formed diol to the stable diacetate, and the whole was
o
stirred for another 30 min at 25 C. After aqueous work-up followed by purification with silica-gel
column chromatography, 1,2-diphenylcyclpropan-1,2-diol diacetate (3a) was obtained in 69% yield
diastereoselectively (Scheme 1).
1) CH2(ZnI)2 (1)
O
AcO
Ph
OAc
Ph
THF, rt, 30 min
Ph
Ph
2) Ac2O
O
2a
3a 69%
Scheme 1. Nucleophilic [2+1] cyclopropanation of bis(iodozincio)methane (1) with benzil (2a)
The stereochemistry of the product was confirmed by X-ray crystallographic analysis. The ORTEP
figure of 3a was shown in Figure 1. The figure shows that the product has cis-configuration. This,
however, seems to be sterically unfavored.
By ab initio calculation, we had shown the reason why the reaction affords a sterically unfavored
cis-configuration.9
The study suggested that the reaction of bis(iodozincio)methane (1) with
1,2-diketone 2 proceeds via a double coordination, that is face-to-face coordination, to afford the
cis-isomer 3 (Scheme 2).

HETEROCYCLES, Vol. 76, No. 2, 2008
1383
Figure 1. X-Ray analysis of cis-1,2-Diacetoxy-1,2-diphenylcyclopropane (3a). Crystal data: M =
310.35, Monoclinic, C2/c, a = 43.816(9), b = 5.922(2), c = 38.178(8) Å, β = 100.53°, V = 9739(3) Å3, Z =
24, ρcacl = 1.270 g / cm3, λ ( Mo ) = 0.71069 Å, F(000) = 3936.00, µ ( Mo ) = 0.88 cm , T = 296
-1
kα
kα
K, 2θ
= 54.0°, R = 0.130 for 4583 reflections (I > 2σ(I)).
max
O
IZnO
Me
OZnI
Me
Me
+
CH2(ZnI)2
Me
O
1
2
3
Zn
Zn
I
I
I
I
I
Zn
CH2
Zn
I
Me
Me
O
O
Me
Me
O
O
Me
Me
O
H2C
H2C
3
Zn
Zn
O
face-to-face
Scheme 2. Coordination pattern of bis(iodozincio)methane (1) with 2,3-butanedione (2)

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HETEROCYCLES, Vol. 76, No. 2, 2008
Other examples are summarized in Table 1. In all cases, the reaction proceeded to give cis-diol
derivatives diastereoselectively. Instead of acetylation, an addition of chlorotrimethylsilane to the
reaction mixture gave the silyl ether (entries 1 and 4). Depending on the substrate, the formed
cyclopropan-1,2-diol possesses reasonable stability that enables isolation by silica-gel column
chromatography (entry 2). In the case of 2b (entries 3, 4 and 5), this substrate tends to form a
conjugated enolate. The dizinc reagent may work not only as nucleophile but also as base,10 and the
cyclopropanation proceeds prior to the enolization of 1,2-diketones. This fact was also explained by the
ab initio calculation.9 The calculation suggested that the dihedral angle formed by two carbonyl groups
of 1,2-diketone in face-to-face initial complex is 47.7o. As the two carbonyl groups are not placed in the
same plane, the carbonyl group at C-1 position can not contribute to facilitate a deprotonation at C-3
position via conjugation in 1-phenylpropan-1,2-diol (2b). The reaction of α-ketoaldehyde accompanied
methylenation to some extent (entry 6). The diketone which has either electron donating group or
electron withdrawing group was also examined (entries 7-9). The reaction of basic nitrogen atom
containing
substrates,
such
as
4,4’-bis(N,N-dimethylamino)benzyl
(2h)
and
1,2-di(2-quinolinyl)ethanedione (2i), did not afford the cyclopropane adducts (entries 10 and 11). The
coordination of basic nitrogen atom to dizinc 1 prevents the interaction of 1 with diketone. Meanwhile,
the reaction of oxygen or sulfur atom containing substrates, 2,2’-furil (2j) and
1,2-di(2-thiophenyl)ethan-1,2-dione (2k), afforded the desired cycloadducts without any interruption of
oxygen or sulfur atom (entries 12 and 13).
1,2-Di(o-tolyl)ethan-1,2-dione (2l) and
1,2-di(2-naphthyl)ethan-1,2-dione (2m) were also converted into sterically unfavored
cis-cyclopropan-1,2-diol derivatives in good yields with high diastereoselectivity (entries 14 and 15).
While the reaction with 1,2-diferrocenylethan-1,2-dione (2n) resulted in methylenation to give α,β-enone
(4) (Scheme 4). It may be explained that 2n is difficult to take the face-to-face coordination because of
the steric hindrance of two ferrocenyl groups (Scheme 3).
CH2
O
O
Fe
Fe
H3O+
THF
CH2(ZnI)2
+
25 oC, 0.5 h
Fe
Fe
O
1
2n
4 95%
Scheme 3. Reaction of bis(iodozincio)methane (1) with 1,2-diferrocenyl-1,2-ethandione (2n)

HETEROCYCLES, Vol. 76, No. 2, 2008
1385
Table 1. [2+1] Reaction of bis(iodozincio)methane (1) with 1,2-dicarbonyl compoundsa
O
O
OEl
R2
El
El+
R2
+
CH2(ZnI)2
R1
THF, rt, 30 min
R1
O
2
1
3
El+
2
substrate
O
3
entry
1
product
yield(%)b
TMSO
OTMS
Ph
Ph
2a
TMSCl
3b
78
Ph
Ph
O
O
HO
Ph
OH
2
3
H3O+
Ac2O
3c
3d
80
98
2b
2b
Ph
O
AcO
OAc
OTMS
Ph
TMSO
2b
2c
TMSCl
Ac2O
3e
3f
4
5
97
59
Ph
O
AcO
OAc
Et
Et
H
Et
Et
O
O
O
O
AcO
OAc
6
7
3g
3h
58c
94
2d
Ac2O
Ac2O
Ph
Ph
H
AcO
OAc
CF3
2e
O
MeO
MeO
MeO
TMSO
CF3
OTMS
OMe
O
2f
3i
8
TMSCl
93
O
MeO
OMe

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HETEROCYCLES, Vol. 76, No. 2, 2008
TMSO
OTMS
Br
O
O
9
2g
TMSCl
TMSCl
3j
80
O
O
Br
Br
Br
N
0d
2h
10
N
O
O
O
O
N
0e
96
77
11
12
13
TMSCl
TMSCl
TMSCl
TMSCl
N
2i
2j
O
O
O
O
TMSO
O
OTMS
O
O
S
3k
3l
O
S
TMSO
S
OTMS
S
2k
2l
TMSO
TMSO
OTMS
OTMS
3m
3n
14
15
82
89
O
TMSCl
2m
O
a 1,2-diketone (2, 1.0 mmol), gem-dizinc 1 (1.2 mmol) and El+ (2.4 mmol) were used.
b Isolated yields. In each entry, only cis-isomer was obtained diastereoselectively.
c The methylenated product (1-phenyl-2-propenone) was also isolated in 17% yield.
d Starting material (2h) was recovered.
e Complex mixture was obtained.

HETEROCYCLES, Vol. 76, No. 2, 2008
1387
Treatment of α-ketoester 5 and α-ketoamides 7 with the dizinc 1 gave the methylenation products 6 and 8
without forming the cyclopropan-1,2-diols (Scheme 4 and 5). The zinc reagent is not nucleophilic
enough to attack ester or amide group.
O
CH2
H3O+
THF
OMe
OMe
+
CH2(ZnI)2
R
R
25 oC, 1 h
O
O
1
5
6
5a
R = Ph
6a
6b
87%
93%
5b
R = CH2=CH(CH2)9
Scheme 4. Reaction of bis(iodozincio)methane (1) with α-ketoester (5)
O
CH2
H3O+
THF
R
R
CH2(ZnI)2
+
Ph
Ph
25 oC, 6 h
O
O
1
7
8
8a 63%
8b 58%
N
N
R =
R =
7a
O
7b
OMe
Scheme 5. Reaction of bis(iodozincio)methane (1) with α-ketoamide (7)
We also tried to perform a ring-opening reaction of the obtained silyl ethers of cyclopropan-1,2-diols with
Lewis acid which has oxidizing ability.11
As shown in Table 2, trimethylsilyl ethers of
cyclopropanediols were converted into 1,3-diketone in good to excellent yields with iron(Ⅲ) chloride in
THF. Considering cyclopropanation of 1,2-diketones, the net transformation can be regarded as
methylene insertion to 1,2-diketone compounds.12
Instead of 1,2-diketone, monotosylimide of benzil 10a , which was prepared following the reported
procedure,13 was treated with dizinc 1. At the end of the reaction, addition of acetic anhydride to the
reaction mixture gave cis-2-aminocyclopropanol acetate 11a diastereoselectively in 95% yield (Scheme
6).

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HETEROCYCLES, Vol. 76, No. 2, 2008
Table 2. Ring opening isomerization into 1,3-diketones (3)a
TMSO
OTMS
O
O
FeCl3
THF, 0 oC
R1
R2
R1
R2
3
9
entry
substrate
TMSO OTMS
product
yield(%)b
96
O
O
9a
9b
1
2
3b
3e
Ph
Ph
Ph
Ph
Ph
TMSO
Ph
OTMS
O
O
83
85
TMSO
OTMS
O
O
O
3i
3j
9c
3
4
MeO
OMe
MeO
TMSO
OMe
OTMS
O
9d
89
Br
Br
Br
Br
TMSO
O
OTMS
O
O
O
O
O
O
S
O
S
5
6
3k
9e
97
99
TMSO
S
OTMS
S
9f
3l
TMSO
OTMS
O
O
9g
7
3n
72
a 1,2-bis(trimethylsiloxy)cyclopropane (3, 0.5 mmol), FeCl3 (0.75 mmol) were used.
b Isolated yields.

HETEROCYCLES, Vol. 76, No. 2, 2008
1389
1) CH2(ZnI)2 (1)
O
AcO
Ph
NHTs
Ph
THF, rt, 30 min
Ph
Ph
2) Ac2O
NTs
10a
11a 95%
Scheme 6. Reaction of bis(iodozincio)methane (1) with α-ketoimine (10a)
The stereochemistry of 11a was confirmed by X-ray analysis (Figure 2). The product was only cis-isomer.
This result indicates that the reaction with α-ketoimine also proceeds via the face-to-face coordination.
Figure 2 X-Ray analysis of cis-1,2-Diacetoxy-1,2-diphenylcyclopropane (11a). Crystal data: M =
421.49, Monoclinic, C2/c, a = 12.7365(13), b = 10.8102(11), c = 16.3267(17) Å, β = 105.936°, V =
2161.5(4) Å3, Z = 4, ρcacl = 1.295 g / cm3, λ ( Mo ) = 0.71073 Å, T = 296 K, 2θ
= 54.0°, R = 0.049
kα
max
for 4711 reflections (I > 2σ(I)).
Other examples are summarized in Table 3. An acidic aqueous work-up and quenching with chloro-
trimethylsilane gave the corresponding products (entries 1 and 2). Electron-donating group, methoxy,
on benzene ring did not disturb the cyclopropanation reaction (entry 3). Tosylimine of 1,2-di(2-
naphthyl)ethan-1,2-dione 10c was also converted into cis-2-aminocyclopropanol derivative 11e in 92%
yield with high diastereoselectivity (entry 4). An attempt to isolate the corresponding 2-amino-
cyclopropanol without a protection with trimethylsilyl group was failed. The ring opening product,
β-hydroxyimide, was isolated quantitatively. Instead of tosylimine, phenylimine was examined for the
cyclopropanation reaction. Treatment of 10d with dizinc 1 followed by aqueous work-up afforded cis-2-
aminocyclopropanol 11f quantitatively (entry 5). In the case of O-methyl oxime 10e or tosylhydrazone
10f, the reaction resulted in the complete recovery of the starting materials (entries 6 and 7).

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HETEROCYCLES, Vol. 76, No. 2, 2008
Table 3. Nucleophilic [2+1]cycloaddition of bis(iodozincio)methane (1) with 1,2-ketoimines (10)a
O
O
NHX
R2
El
El+
R2
+
CH2(ZnI)2
R1
R1
THF, rt, 30 min
NX
10
1
11
yield(%)b
97
El+
entry
1
product
substrate
O
HO
NHTs
Ph
H3O+
Ph
10a
10a
11a
11c
Ph
Ph
NTs
TMSO
NHTs
2
3
TMSCl
H3O+
>99
>99
Ph
Ph
HO
NHTs
OMe
10b
O
11d
NTs
NTs
MeO
MeO
OMe
TMSO
NHTs
O
O
4
5
TMSCl
11e
11f
92
10c
HO
Ph
NHPh
Ph
H3O+
Ph
NPh
10d
>99
Ph
O
O
H3O+
Ph
0c
6
7
10e
10f
Ph
Ph
NOMe
H3O+
Ph
0c
NNHTs
+
a α
-keto imine (10, 1.0 mmol), gem-dizinc 1 (2.0 mmol) and El (2.4 mmol) were used.
b Isolated yields. In each entry, only cis-isomer was formed diastereoselectively.
c Starting material was recovered.

HETEROCYCLES, Vol. 76, No. 2, 2008
1391
CONCLUSION
We showed the scope of the nucleophilic [2+1]cycloaddition of bis(iodozincio)methane and 1,2-diketones
or α-ketoimines. Various substrates, which can coordinate with dizinc 1 as the face-to-face manner,
were converted into cis-cyclopropan-1,2-diol derivatives diastereoselectively. These products have
potential to apply for effective ligands of organometallic chemistry, pharmaceutical applications and
functionalized materials.
EXPERIMENTAL
All solvents except tetrahydrofuran were used as obtained from commercial suppliers. Tetrahydrofuran
was distilled over benzophenone–ketyl. Zinc powder was used after washing with 10% HCl according to
the reported procedure.14
forced-flow chromatography on Kanto Chemical Co., INC. Silica gel 60 N (spherical, neutral).
13
Chromatographic purification of products was accomplished using
1
H and C NMR spectra were recorded on Varian Gemini-2000 (300 MHz and 75 MHz, respectively)
1
instrument and are internally referenced to residual protio solvent signals. Data for H NMR are
reported as chemical shift (δ ppm), multiplicity (s = singlet, d = doublet, t = triplet, q = quartet, m =
13
multiplet), coupling constant (Hz), integration, and assignment. Data for C NMR are reported as
chemical shift.
For the X-ray diffraction, a crystal was mounted on a glass fiber coated with epoxy resin. Measurements
were made on a Rigaku Mercury charge-coupled device (CCD) system with graphite monochromated Mo
radiation.
kα
Bis(iodozincio)methane (1): A mixture of Zn (25 mmol), diiodomethane (1.0 mmol), and PbCl (0.01
2
mmol) in THF (2.0 mL) was sonicated for 1 h in an ultrasonic cleaner bath under Ar. To the mixture,
diiodomethane (10 mmol) in THF (20 mL) was added dropwise over 15 min at 0 ° C with vigorous
stirring. The mixture was stirred for 2 h at 0 ° C. After the stirring was stopped, the reaction vessel
was stood undisturbed for several hours. Excess zinc was separated by sedimentation. 1H NMR
spectra of the obtained supernatant showed a broad singlet at -1.2 ppm at 0 ° C, which corresponded to
the methylene proton of 1. The supernatant was used for the further reaction as a solution of 1 in THF
(0.5–0.6 M). Bis(Iodozincio)methane in THF can be kept unchanged at least for a month in the sealed
reaction vessel.
General Procedure for the preparation of 1,2 -cyclopropanediol: To a solution of 1,2-diketone (1.0
mmol) in THF (3 mL), dizinc 1 (1.2 mmol) was added dropwise at 25 °C. The mixture was stirred 30

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HETEROCYCLES, Vol. 76, No. 2, 2008
min. Quenching reagent (2.4 mmol, water, acetic anhydride, and chlorotrimethylsilane) was added
dropwise and the resulting mixture was stirred for another 30 min. The mixture was poured into sat.
NH Cl aq and extracted with Et O. The combined ethereal phases were washed with brine and dried
4
2
over Na SO . Purification on a neutral silica-gel column chromatography gave the corresponding
2
4
1,2-cyclopropanediol derivative.
cis-1,2-Diacetoxy-1,2-diphenylcyclopropane (3a): 1H NMR (300MHz, CDCl3) δ 7.28-7.20 (m, 4H),
13
7.18-7.10 (m, 6H), 2.51 (d, J = 9.0 Hz, 1H), 2.11 (s, 6H), 1,83 (d, J = 9.0 Hz, 1H); C NMR (75MHz,
CDCl3) δ 170.1, 135.3, 128.8, 127.8, 64.9, 23.8, 21.1. Anal. Calcd for C19H18O4: C, 73.53; H, 5.85.
Found: C, 73.25; H, 5.95.
cis-1,2-Bis(trimethylsiloxy)-1,2-diphenylcyclopropane (3b): 1H NMR (300MHz, CDCl3) δ 7.17-6.90
(m, 10H), 2.18 (d, J = 7.5 Hz, 1H), 1,48 (d, J = 7.5 Hz, 1H), 0.08 (s, 18H); 13C NMR (75MHz, CDCl3) δ
140.0, 127.9, 127.5, 126.5, 64.8, 23.1, 0.90. Anal. Calcd for C21H30O2Si2: C, 68.05; H, 8.16. Found:
C, 67.80; H, 7.93.
1
cis-1,2-Dihydroxy-1-methyl-2-phenylcyclopropane (3c): H NMR (500MHz, CDCl3) δ 7.60-7.20 (m,
5H), 3.85 (bs, 2H), 1.27 (d, J = 7.5 Hz, 1H), 1.13 (s, 3H), 0.98 (d, J = 7.5 Hz, 1H). 13C NMR
(125MHz, C6D6) δ 140.1, 128.4, 128.3, 127.3, 62.0, 58.8, 24.5, 20.5. HRMS calcd for C10H12O2 M+:
164.0837, found 164.0834.
cis-1,2-Diacetoxy-1-methyl-2-phenylcyclopropane (3d): 1H NMR (300MHz, CDCl3) δ 7.65-7.56 (m,
2H), 7.38 – 7.20 (m, 3H), 2.09 (s, 3H), 1.92 (s, 3H), 1.68 (d, J = 9.0 Hz, 1H), 1,39 (d, J = 9.0 Hz, 1H),
13
1.21 (s, 3H); C NMR (75MHz, CDCl3) δ 170.6, 170.2, 135.6, 129.6, 128.3, 128.2, 125.9, 63.5, 60.5,
22.8, 21.0, 20.7, 18.3. Anal. Calcd for C14H16O4: C, 67.73; H, 6.50. Found: C, 67.84; H, 6.59.
cis-1,2-Bis(trimethylsiloxy)-1-methyl-2-phenylcyclopropane (3e) : 1H NMR (300MHz, CDCl3) δ
7.41-7.15 (m, 5H), 1.34 (d, J = 6.9 Hz, 1H), 1,06 (d, J = 6.9 Hz, 1H), 1.05 (s, 3H), 0.23 (s, 9H), 0.03 (s,
13
9H); C NMR (75MHz, CDCl3) δ 141.1, 128.0, 127.9, 126.9, 63.7, 59.7, 24.1, 22.2, 1.24, 0.82. Anal.
Calcd for C16H28O2Si2: C, 62.28; H, 9.15. Found: C, 61.98; H, 9.27.
cis-1,2-Diacetoxy-1,2-diethylcyclopropane (3f): 1H NMR (300MHz, CDCl3) δ 1.98 (s, 6H), 1.84 (ddq,
J = 15.0, 7.5, 0.9 Hz, 2H), 1.74 (dq, J = 15.0, 7.5 Hz, 2H), 1.07 (dt, J = 8.4, 0.9 Hz, 1H), 1.00 (t, J = 7.5

HETEROCYCLES, Vol. 76, No. 2, 2008
1393
Hz, 6H), 0.87 (d, J = 8,4 Hz, 1H); 13C NMR (75MHz, CDCl3) δ 170.4, 64.1, 24.2, 23.1, 20.9, 9.4.
HRMS calcd for C11H19O4 [M + H]+: 215.1283, found 215.1289.
cis-1,2-Diacetoxy-1-phenylcyclopropane (3g) : 1H NMR (300MHz, CDCl3) δ 7.51-7.40 (m, 2H),
7.41-7.28 (m, 3H), 4.26 (dd, J = 8.1, 4.8 Hz, 1H), 2.13 (s, 3H), 2.04 (s, 3H), 1.80 (dd, J = 8.4, 8.4 Hz,
1H), 1,49 (dd, J = 8.4, 4.8 Hz, 1H); 13C NMR (75MHz, CDCl3) δ 171.2, 170.2, 137.5, 128.4, 128.1, 127.7,
59.9, 55.0, 20.8, 20.4, 18.8. HRMS calcd for C13H15O4 [M + H]+: 235.0970, found 235.0963.
cis-1,2-Diacetoxy-1-(4-anisyl)-2-(4-trifluoromethylphenyl)cyclopropane (3h): 1H NMR (500MHz,
CDCl3) δ 7.40 (d, J = 8.0 Hz, 2H), 7.26 (d, J = 8 Hz, 2H), 7.25-7.22 (m, 2H), 6.70-6.67 (m, 2H), 3.72 (s,
13
3H), 2.43 (d, J = 9.0 Hz, 1H), 2.14 (s, 3H), 2.07 (s, 3H), 1.85 (d, J = 9 Hz, 1H); C NMR (125MHz,
CDCl3) δ 170.2, 170.0, 159.4, 140.0, 131.3, 129.5 (q, J = 32.5 Hz), 128.0, 126.4, 124.8 (q, J = 3.9 Hz),
123.9 (q, J = 270.6 Hz), 113.4, 65.2, 64.0, 55.1, 24.3, 21.13, 21.07. HRMS calcd for C21H19O5F3 M+:
408.1185, found 408.1193.
cis-1,2-Bis(trimethylsiloxy)-1,2-di(4-anisyl)cyclopropane (3i): 1H NMR (500MHz, CDCl3) δ 7.04-7.01
(m, 4H), 6.62-6.59 (m, 4H), 3.69 (s, 6H), 2.02 (d, J = 7.5 Hz, 1H), 1.37 (d, J = 7.5 Hz, 1H), 0.05 (s, 18H);
13C NMR (125MHz, CDCl3) δ 158.0, 132.4, 129.1, 112.8, 64.4, 55.0, 24.0, 1.08. Anal. Calcd for
C23H34O4Si2: C, 64.14; H, 7.96. Found: C, 64.27; H, 7.97. HRMS calcd for C23H34O4Si2 M+: 430.1996,
found 430.1993.
cis-1,2-Bis(trimethylsiloxy)-1,2-di(4-bromophenyl)cyclopropane (3j): 1H NMR (500MHz, CDCl3)
δ 7.22 (d, J = 8.5 Hz, 4H), 6.96 (d, J = 8.5 Hz, 4H), 2.08 (d, J = 7.5 Hz, 1H), 1.47 (d, J = 7.5 Hz, 1H),
13
0.06 (s, 18H); C NMR (125MHz, CDCl3) δ 138.9, 130.9, 129.4, 120.8, 64.3, 23.8, 1.07. Anal. Calcd
for C21H28O2Br2Si2: C, 47.73; H, 5.34. Found: C, 47.64; H, 5.24. HRMS calcd for C21H28O2Br2Si2
M+: 525.9995, found 525.9988.
cis-1,2-Di(2-furyl)-1,2-bis(trimethylsilyloxy)cyclopropane (3k): 1H NMR (500MHz, CDCl3) δ 7.22 (dd,
J = 1.5, 1.0 Hz, 2H), 6.16 (dd, J = 3.5, 1.5 Hz, 2H), 5.92 (dd, J = 3.5, 1.0 Hz, 2H), 1.88 (d, J = 6.5 Hz,
13
1H), 1.41 (d, J = 6.5 Hz, 1H), 0.10 (s, 18H); C NMR (125MHz, CDCl3) δ 153.4, 141.4, 110.1, 107.6,
58.7, 25.1, 0.54. Anal. Calcd for C17H26O4Si2: C, 58.25; H, 7.48. Found: C, 58.04; H, 7.41. HRMS
calcd for C17H26O4Si2 M+: 350.1370, found 350.1369.

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cis-1,2-Di(thiophen-2-yl)-1,2-bis(trimethylsilyloxy)cyclopropane (3l): 1H NMR (500MHz, CDCl3)
δ 7.07 (dd, J = 5.0, 1.0 Hz, 2H), 6.73 (dd, J = 5.0, 3.5 Hz, 2H), 6.59 (dd, J = 3.5, 1.0 Hz, 2H), 2.01 (d, J =
13
7.5 Hz, 1H), 1.66 (d, J = 7.5 Hz, 1H), 0.13 (s, 18H); C NMR (125MHz, CDCl3) δ 145.2, 125.8, 125.2,
125.0, 62.0, 28.9, 0.93. HRMS calcd for C17H26O2S2Si2 M+: 382.0913, found 382.0915.
cis-1,2-Bis(trimethylsiloxy)-1,2-di(2-tolyl)cyclopropane (3m): 1H NMR (300MHz, CDCl3) δ 7.05-6.95
(m, 4H), 6.82-6.77 (m, 4H), 2.57 (s, 6H), 2.01 (d, J = 7.2 Hz, 1H), 1.41 (d, J = 7.2 Hz, 1H), -0.01 (s,
18H); 13C NMR (75Hz, CDCl3) δ 138.9, 138.2, 130.7, 127.7, 126.9, 124.5, 65.1, 25.8, 21.3, 1.38.
Anal. Calcd for C23H34O2Si2: C, 69.29; H, 8.60. Found: C, 69.02; H, 8.44. HRMS calcd for
C23H34O2Si2 M+: 398.2097, found 398.2094.
cis-1,2-Bis(trimethylsiloxy)-1,2-di(2-naphtyl)cyclopropane (3n): 1H NMR (500MHz, CDCl3) δ
7.63-7.59 (m, 6H), 7.47 (d, J = 9.0Hz, 2H), 7.35-7.29 (m, 6H), 2.48 (d, J = 7.5 Hz, 1H), 1.62 (d, J = 7.5
13
Hz, 1H), 0.09 (s, 18H); C NMR (125MHz, CDCl3) δ 137.5, 132.6, 132.2, 127.8, 127.4, 127.3, 126.5,
126.2, 125.6, 125.5, 65.2, 24.0, 1.14. Anal. Calcd for C29H34O2Si2: C, 73.99; H, 7.28. Found: C,
73.93; H, 7.32. HRMS calcd for C29H34O2Si2 M+: 470.2097, found 470.2101.
1,2-Diferrocenylpropenone (4): 1H NMR (500MHz, CDCl3) δ 5.77 (s, 1H), 5.68 (s, 1H), 4.84 (t, J = 2.0
Hz, 2H), 4.54 (t, J = 2.0 Hz, 2H), 4.52 (s, 2H), 4.29 (s, 2H), 4.23 (s, 5H), 4.14 (s, 5H); 13C NMR
(125MHz, CDCl3) δ 200.3, 147.4, 114.4, 80.8, 78.4, 72.3, 71.0, 70.0, 69.7, 69.0, 67.1. Anal. Calcd for
C23H20OFe2: C, 65.14; H, 4.75. Found: C, 64.86; H, 4.78. HRMS calcd for C23H20OFe2 M+: 424.0213,
found 424.0209.
Methyl 2-methylene-2-phenylacetate (6a): 1H NMR (500MHz, CDCl3) δ 7.43-7.32 (m, 5H), 6.37 (d, J
= 1.0 Hz, 1H), 5.90 (d, J = 1.0 Hz, 1H), 3.83 (s, 3H); 13C NMR (125MHz, CDCl3) δ 167.3, 141.3, 136.7,
128.3, 128.2, 128.1, 126.9, 52.2. HRMS calcd for C10H10O2 M+: 162.0681, found 162.0680.
Methyl 2-methylene-12-tridecenoate (6b): 1H NMR (500MHz, CDCl3) δ 6.12 (dt, J = 1.5, 0.5 Hz, 1H),
5.81 (ddt, J = 17.0, 10.0, 6.5 Hz, 1H), (dt, J = 1.5, 1.5 Hz, 1H), 4.99 (ddt, J = 17.0, 2.0, 1.5 Hz, 1H), 4.93
(ddt, J = 10.0, 2.0, 1.5 Hz, 1H), 3.75 (s, 3H), 2.29 (ddt, J = 7.5, 1.0, 0.5 Hz, 2H), 2.06-2.01 (m, 2H), 1.45
(tt, J = 7.5, 7.5 Hz, 2H), 1.37 (tt, J = 7.5, 7.5 Hz, 2H), 1.34-1.25 (m, 10H) ; 13C NMR (125MHz, CDCl3) δ
167.8, 140.8, 139.2, 124.4, 114.1, 51.7, 33.8, 31.9, 29.5, 29.43, 29.37, 29.2, 29.1, 28.9, 28.3. Anal.
Calcd for C15H26O2: C, 75.58; H, 10.99. Found: C, 75.49; H, 10.71. HRMS calcd for C15H26O2 M+:

HETEROCYCLES, Vol. 76, No. 2, 2008
1395
238.1933, found 238.1935.
1
2-Phenyl-1-piperidin-1-ylpropenone (8a): H NMR (500MHz, CDCl3) δ 7.44-7.42 (m, 2H), 7.37-7.28
(m, 3H), 5.71 (s, 1H), 5.33 (s, 1H), 3.71-3.65 (m, 2H), 3.32-3.30 (m, 2H), 1.63-1.60 (m, 4H), 1.40-1.33
(m, 2H); 13C NMR (125MHz, CDCl3) δ 169.1, 145.2, 135.7, 128.7, 128.5, 125.7, 113.3, 48.0, 42.4, 26.3,
25.6, 24.5. HRMS calcd for C14H17NO M+: 215.1310, found 215.1306.
(S)-Methyl 1-(2-phenylacryloyl)pyrrolidine-2-carboxylate (8b):
1H NMR (500MHz, CDCl3)
δ 7.53-7.50 (m, 2H), 7.42-7.29 (m, 3H), 5.76 (s, 0.80H), 5.68 (s, 0.20H), 5.49 (s, 0.80H), 5.34 (s, 0.20H),
4.62 (dd, J = 8.0, 5.0 Hz, 0.80H), 4.24 (dd, J = 6.0, 2.5 Hz), 3.79 (s, 2.4H), 3.49 (s, 0.6H), 3.39-3.31 (m,
1.6H), 2.29-2.21 (m, 0.8H), 2.18-2.07 (m, 0.2H), 2.02-1.91 (m, 2H), 1.88-1.80 (m, 1H); 13C NMR
(125MHz, CDCl3) δ 172.60, 172.58, 169.4, 169.3, 145.5, 145.4, 135.3, 135.1, 128.8, 128.7, 128.6, 128.5,
126.1, 125.9, 115.25, 115.17, 60.4, 58.4, 52.3, 52.1, 48.5, 46.0, 31.2, 29.4, 24.9, 22.6. HRMS calcd for
C15H17NO3 M+: 259.1208, found 259.1205.
General Procedure for the p
reparation of 1,3-diketone
:
To
a
solution of cis-1,2-
bis(trimethylsiloxy)-1,2-dialkylcyclopropane (0.5 mmol) in THF (1 mL), FeCl3 (0.75 mmol) was added at
o
0 C. The mixture was stirred for 30 min. The mixture was poured into 1NHClaq and extracted with
EtOAc. The combined organic phases were washed with brine and dried over Na2SO4. Purification on
a neutral silica-gel column chromatography gave the corresponding 1,3-diketone.
1,3-Diphenyl-1,3-propanedione (9a): 1H NMR (300MHz, CDCl3) δ 8.00 (d, J = 7.0 Hz, 4H), 7.56 (t, J =
13
7.0 Hz, 2H), 7.50 (dd, J = 7.0, 7.0 Hz, 4H), 6.87 (s, 1H); C NMR (75MHz, CDCl3) δ 185.7, 135.5,
132.4, 128.7, 127.1, 93.1. HRMS calcd for C15H12O2 M+: 224.0837, found 224.0836.
1-Methyl-3-phenyl-1,3-propanedione (9b): 1H NMR (300MHz, CDCl3) δ 7.88 (d, J = 7.0 Hz, 2H), 7.52
(t, J = 7.5 Hz, 1H), 7.45 (dd, J = 7.5, 7.0 Hz, 2H), 6.18 (s, 1H), 2.20 (s, 3H); 13C NMR (75MHz, CDCl3) δ
193.8, 183.3, 134.8, 132.3, 128.6, 127.0, 96.7, 25.8. HRMS calcd for C10H10O2 M+: 162.0681, found
162.0679.
1,3-Di(4-anisyl)-1,3-propanedione (9c): 1HNMR (500MHz, CDCl3) δ 7.96 (d, J = 9.0 Hz, 4H), 6.98 (d,
13
J = 9.0 Hz, 4H), 6.74 (s, 1H), 3.89 (s, 6H); CNMR (125MHz, CDCl3) δ 184.6, 163.0, 129.1, 128.2,
113.9, 91.5, 55.5. HRMS calcd for C17H16O4 M+: 284.1049, found 284.1048.

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1,3-Di(4-bromophenyl)-1,3-propanedione (9d): 1H NMR (500MHz, CDCl3) δ 7.85 (d, J = 8.5 Hz, 4H),
13
7.63 (d, J = 8.5 Hz, 4H), 6.77 (s, 1H); C NMR (125MHz, CDCl3) δ 184.7, 134.2, 132.0, 128.7, 127.5,
79
92.9. HRMS calcd for C15H10O2 Br2 M+: 379.9048, found 379.9044.
1
1,3-Di(2-furyl)-1,3-propanedione (9e): H NMR (500MHz, CDCl3) δ 7.61 (dd, J = 1.5, 1.0 Hz, 2H),
7.20 (dd, J = 3.5, 1.0 Hz, 2H), 6.65 (s, 1H), 6.58 (dd, J = 3.5, 1.5 Hz, 2H); 13C NMR (125MHz, CDCl3) δ
174.7, 150.3, 146.1, 115.5, 112.6, 92.1. HRMS calcd for C11H8O4 M+: 204.0423, found 204.0421.
1
1,3-Di(2-thiophenyl)-1,3-propanedione (9f): H NMR (500MHz, CDCl3) δ 7.78 (dd, J = 4.0, 1.0 Hz,
13
2H), 7.62 (dd, J = 5.0, 1.0 Hz, 2H), 7.17 (dd, J = 5.0, 4.0 Hz, 2H), 6.54 (s, 1H); C NMR (125MHz,
CDCl3) δ 178.8, 140.6, 132.0, 130.0, 128.3, 92.6. HRMS calcd for C11H8O2S2 M+: 235.9966, found
235.9971.
1
1,3-Di(2-naphtyl)-1,3-propanedione (9g): HNMR (500MHz, CDCl3 ) δ 8.60 (d, J = 1.5 Hz, 2H), 8.08
(d, J = 8.5, 2.0 Hz, 2H), 8.02 (d, J = 7.5 Hz, 2H), 7.96 (d, J = 8.5 Hz, 2H), 7.91 (d, J = 8.0 Hz, 2H),
13
7.63-7.56 (m, 4H), 7.16 (s, 1H); CNMR (125MHz, CDCl3) δ 185.6, 135.3, 132.8, 132.8, 129.4, 128.5,
128.4, 128.2, 127.8, 126.8, 123.3, 93.8. HRMS calcd for C23H16O2 M+: 324.1150, found 324.1152.
General Procedure for the preparation of 2-aminocyclopropanol: To a solution of α-keto imine (1.0
mmol) in THF (4 mL), dizinc 1 (2.0 mmol) was added dropwise at 25 °C. The mixture was stirred for
30 min. Quenching reagent (2.4 mmol, water, acetic anhydride, and chlorotrimethylsilane) was added
dropwise and the resulting mixture was stirred for another 30 min. The mixture was poured into sat.
NH Claq, then sat. NaHCO3 aq was added to neutralize and extracted with Et O. The combined
4
2
ethereal phases were washed with brine and dried over Na SO . Purification on a neutral silica-gel
2
4
column chromatography gave the corresponding 2-aminocyclopropanol derivative.
cis-N-(2-Acetoxy-1,2-diphenylcyclopropyl)-4-methylbenzenesulfonamide (11a): 1HNMR (300MHz,
CDCl3 ) δ 7.41 (d, J = 8.4 Hz, 2H), 7.07-6.98 (m, 7H), 6.90-6.83 (m, 5H), 5.83 (s, 1H), 2.39 (d, J = 8.4
13
Hz, 1H), 2.30 (s, 3H), 2.18 (d, J = 8.4 Hz, 1H), 2.13 (s, 3H); CNMR (75MHz, CDCl3) δ 171.0, 143.1,
137.9, 135.9, 134.9, 129.3, 129.0, 128.5, 128.0, 127.93, 127.87, 127.4, 127.1, 66.2, 46.7, 22.4, 21.8, 21.7.
HRMS calcd for C24H23NO4S M+: 421.1348, found 421.1357.
cis-N-(2-Hydroxy-1,2-diphenylcyclopropyl)-4-methylbenzenesulfonamide (11b): 1HNMR (300MHz,

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1397
CDCl3) δ 7.45 (d, J = 8.1 Hz, 2H), 7.06-7.02 (m, 7H), 6.89-6.83 (m, 5H), 6.04 (s, 1H), 3.39 (bs, 1H), 2.32
13
(s, 3H), 2.23 (d, J = 7.8Hz, 1H), 1.77 (d, J = 7.8 Hz, 1H); CNMR (75MHz, CDCl3) δ 143.2, 137.8,
137.7, 136.3, 129.3, 129.2, 128.0, 127.7, 127.5, 127.48, 127.3, 126.9, 63.4, 47.5, 23.8, 21.8. HRMS
calcd for C22H21NO3S M+: 379.1242, found 379.1241.
cis-N-(2-Trimethylsiloxy-1,2-diphenylcyclopropyl)-4-methylbenzenesulfonamide (11c):
1HNMR
(500MHz, CDCl3) δ 7.49-7.47 (m, 2H), 7.10-7.07 (m, 2H), 7.04-6.98 (m, 5H), 6.95-6.92 (m, 2H),
6.90-6.86 (m, 3H), 5.91 (s, 1H), 2.34 (s, 3H), 2.31 (d, J = 8.0 Hz, 1H), 1.42 (d, J = 8.0 Hz, 1H), -0.01 (s,
9H); 13CNMR (125MHz, CDCl3) δ 142.8, 138.3, 137.5, 136.6, 129.1, 128.8, 127.8, 127.6, 127.31, 127.29,
127.28, 126.4, 64.0, 45.2, 21.8, 21.4, 0.72. HRMS calcd for C25H29NO3SSi M+: 451.1637, found
451.1634.
cis-N-(2-Hydroxy-1,2-di-4-anisylcyclopropyl)-4-methylbenzenesulfonamide (11d): 1HNMR (300MHz,
CDCl3) δ 7.45 (d, J = 8.1 Hz, 2H), 7.06 (d, J = 8.1 Hz, 2H), 6.98 (d, J = 9.0 Hz, 2H), 6.78 (d, J = 8.7 Hz,
2H), 6.61 (d, J = 9.0 Hz, 2H), 6.40 (d, J = 8.7 Hz, 2H), 3.67 (s, 3H), 3.63 (s, 3H), 2.33(s, 3H), 2.07 (d, J =
13
7.5 Hz, 1H), 1.61 (d, J = 7.5 Hz, 1H); CNMR (75MHz, CDCl3) δ 157.4, 157.1, 139.0, 130.7, 129.2,
128.9, 128.4, 127.8, 127.5, 127.2, 126.9, 126.2, 111.5, 111.4, 61.1, 53.3, 45.7, 22.4. HRMS calcd for
C24H25NO5S M+: 439.1453, found 439.1453.
cis-N-(2-Trimethylsiloxy-1,2-di-2-naphthylcyclopropyl)-4-methylbenzenesulfonamide (11e):
1HNMR (300MHz, C6D6) δ 7.60-6.94 (m, 16H), 6.39-6.36 (m, 2H), 6.20 (s, 1H), 2.60 (d, J = 8.1 Hz, 1H),
2.15 (d, J = 8.1 Hz, 1H), 1.63 (s, 3H), 0.05 (s, 9H); 13CNMR (75MHz, C6D6) δ 142.0, 139.3, 135.8, 134.4,
132.8, 132.73, 132.66, 132.3, 128.6, 127.7, 127.6, 127.4, 127.3, 127.0, 126.5, 126.1, 126.0, 125.8, 125.6,
125.5, 64.8, 46.3, 23.6, 20.8, 0.9. HRMS calcd for C33H33O3NSSi M+: 551.1950, found 551.1950.
1
1,2-Diphenyl-2-(phenylamino)cyclopropanol (11f): HNMR (300MHz, C6D6) δ 7.15-6.67 (m, 15H),
2.02 (d, J = 7.2 Hz, 1H), 1.08 (d, J = 7.2 Hz, 1H); 13CNMR (300MHz, C6D6) δ 147.2, 139.7, 138.6, 129.2,
128.8, 128.4, 128.0, 127.4, 126.1, 120.0, 118.5, 115.2, 66.5, 47.0, 25.0. Anal. Calcd for C21H19NO: C,
83.69; H, 6.35. Found: C, 83.39; H, 6.16.; HRMS calcd for C21H19NO M+: 301.1463, found
301.1459.
ACKNOWLEDGEMENTS
This work was supported financially by the Japanese Ministry of Education, Culture, Sports, Science and
Technology, and by Kyoto University, International Innovation Centre. The authors acknowledge the

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support by the Global COE Program "Integrated Materials Science" (#B-09).
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