Copper(0)-induced aminocyclopropanation of olefins via deselenation of N,N-disubstituted aromatic selenoamides

Article abstract of DOI:10.1016/j.tet.2008.07.101

Upon heating of a mixture of N,N-disubstituted aromatic selenoamides and several electron-deficient olefins in the presence of copper(0) powder, a novel deselenative cyclopropanation takes place to afford the corresponding aminocyclopropanes in good yields. When acrylonitrile is employed as an electron-deficient olefin, the aminocyclopentanation occurs in preference to the aminocyclopropanation by prolonging the reaction time. The obtained aminocyclopropane derivatives can be converted to the corresponding 1,4-dicarbonyl compounds upon treatment with 2 N HCl.

Full text of DOI:10.1016/j.tet.2008.07.101

Tetrahedron 64 (2008) 9983–9988
Contents lists available at ScienceDirect
Tetrahedron
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Copper(0)-induced aminocyclopropanation of olefins via deselenation
of N,N-disubstituted aromatic selenoamides
*
Takenori Mitamura, Akihiro Nomoto, Motohiro Sonoda, Akiya Ogawa
Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Nakaku, Sakai, Osaka 599-8531, Japan
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 25 June 2008
Received in revised form 24 July 2008
Accepted 24 July 2008
Available online 29 July 2008
Upon heating of a mixture of N,N-disubstituted aromatic selenoamides and several electron-deficient
olefins in the presence of copper(0) powder, a novel deselenative cyclopropanation takes place to afford
the corresponding aminocyclopropanes in good yields. When acrylonitrile is employed as an electron-
deficient olefin, the aminocyclopentanation occurs in preference to the aminocyclopropanation by
prolonging the reaction time. The obtained aminocyclopropane derivatives can be converted to the
corresponding 1,4-dicarbonyl compounds upon treatment with 2 N HCl.
Keywords:
Selenoamide
Ó 2008 Elsevier Ltd. All rights reserved.
Copper(0)
Deselenation
Cyclopropanation
Aminocyclopropane
Aminocarbene species
1. Introduction
copper and the high reactivity of carbon–selenium double bond.4
Some other low-valent metal reagents such as Zn, Zn–Cu,
N,N-Disubstituted selenoamides are among the most stable
selenocarbonyl compounds and they can be prepared conve-
niently.1 Therefore, the selenoamide is a useful candidate for
investigation of the chemical properties of selenocarbonyl com-
pounds bearing an adjacent heteroatom.2 In 1991, we have reported
the copper(0)-induced deselenative coupling reaction of seleno-
amides. For example, heating of N-(selenobenzoyl)piperidine (1a)
in toluene at 110 ꢀC in the presence of copper(0) afforded the
corresponding 1,2-enediamine (2a) in good yield (Eq. 1).3
and W(CO)6 did not cause the deselenative coupling reaction
satisfactorily, whereas the mixed system of Sm metal and SmI2
5
as a powerful one-electron reducing reagent works well for
this transformation.6–8 When N-benzyl benzeneselenoamide
(1b) and benzeneselenoamide (1c) were used as N-monosubsti-
tuted and N-unsubstituted selenoamides, the corresponding imine
and nitrile were obtained as the deselenation products (Eqs. 2
and 3).
Se
Cu(0) (2 equiv)
Se
Ph
N
H
Ph
Ph
N
Ph
ð2Þ
Ph
toluene, 110 °C
[M]
toluene, 110 °C, 4 h
N
Ph
N
1b
86%
N
Ph
2a
1a
ð1Þ
M: Cu(0)
2 equiv
1 equiv
2 equiv
∼100%[E/Z=82/18]
48%
trace
trace
20%
98%
Se
Cu(0) (2 equiv)
toluene, 110 °C
Zn
Ph
C
N
ð3Þ
Zn-Cu
W(CO)6
Sm/SmI2
Ph
NH2
1c
45%
The driving forces of this deselenative coupling reaction are
conceivably the higher affinity of selenium for soft metals such as
Although the precise mechanism for these deselenation re-
actions waits for the further detailed mechanistic investigations,
a possible reaction pathway may involve the formation of -amino-
-aminocarbenoids) as a key intermediate
a
carbene species (or
a
* Corresponding author. Tel./fax: þ81 72 254 9290.
E-mail address: ogawa@chem.osakafu-u.ac.jp (A. Ogawa).
(A).9
0040-4020/$ – see front matter Ó 2008 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2008.07.101

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T. Mitamura et al. / Tetrahedron 64 (2008) 9983–9988
Table 2
Copper(0)-induced aminocyclopropanation of olefins (3) with selenoamides (1)a
Ar
NR2
(A)
Entry
Selenoamide
Olefin
Product
R'
NR2
Yieldb (%)
To capture the active intermediate (A) with olefins, we exam-
ined the copper(0)-induced reaction of N,N-disubstituted seleno-
amides in the presence of several olefins, and have found a novel
aminocyclopropanation of olefins (Eq. 4).
Se
R'
Ar
NR2
NR2
Ar
Ar
n
CO2 Bu
N
R'
1
4ac
66
Se
Cu(0)
+
ð4Þ
3c
R'
1a
Ar
NR2
Ar
NR2
CO2Me
2
3
4
5
4ad
4ae
4af
4ag
68
70
75
44
3d
CO2Et
2. Results and discussions
3e
t
We first examined the reaction of N-(selenobenzoyl)piperidine
(1a) with several olefins in the presence of copper(0) powder (Table
1). In the cases of cyclohexene (3a) and n-butyl vinyl ether (3b), the
copper(0)-induced thermal reaction of selenoamide (1a) afforded
the deselenative coupling product (2a) in 56% and 25% (GLC) yields,
respectively (entries 1 and 2). In sharp contrast, when n-butyl ac-
rylate (3c) was employed for this reaction, a novel amino-
cyclopropanation of 3c with 1a took place successfully at 110 ꢀC for
4 h, to give the corresponding aminocyclopropane (4ac)10 in good
yield (entries 3–5).
CO2 Bu
3f
COMe
3g
Ph
6
7
4ah
4dc
46
34
3h
NMe2
N
3c
1d
1e
If the reaction involves the formation of a-aminocarbene species
Me
8
3c
3c
4ec
4fc
68
(A), they may have nucleophilic character through the conjugation
shown in Eq. 5, and prefer the reaction with electron-poor olefins
like 3c.11,12
Cl
9c
ND
N
Ar
NR2
Ar
NR2
ð5Þ
(A)
1f
a
Reaction conditions: selenoamide (1a, 1.0 mmol), olefins (2, 1 mL), Cu(0)
The representative results of the aminocyclopropanation of
(4.0 mmol), 110 ꢀC, 4 h.
b
several olefins are summarized in Table 2. Methyl, ethyl, and tert-
butyl acrylates (3d, 3e, and 3f) underwent aminocyclopropanation
with N-(selenobenzoyl)piperidine (1a) to afford the corresponding
aminocyclopropanes (4ad, 4ae, and 4af) in good yields, respectively
(entries 2, 3, and 4). Similar conditions can be employed with
methyl vinyl ketone (3g) and styrene (3h), 4ag and 4ah were
obtained in moderate yields (entries 5 and 6). In the cases of
Isolated yield.
c
1,2-Enediamine (2f) was obtained in 88% isolated yield (E/Z¼84:16).
allylbenzene and vinyl acetate, unfortunately, oligomerization of
these olefins proceeded exclusively.
Next, we examined the reactions using several selenoamides.
The thermal reaction of N,N-dimethyl benzeneselenoamide (1d)
with n-butyl acrylate (3c) in the presence of copper(0) provided
4dc in moderate yield (entry 7). Aromatic selenoamides such as
N-(4-methyl-selenobenzoyl)piperidine (1e) also afforded the cor-
responding aminocyclopropane (4ec) in good yield (entry 8). On
the other hand, N-(3-chloro-selenobenzoyl)piperidine (1f) did not
provide the desired aminocyclopropane (4fc), but 1,2-enediamine
(2f) was obtained in 88% (E/Z¼84:16) yield (entry 9). Probably
owing to the influence of Cl substituent on the reactivity of amino-
carbene species, the aminocyclopropanation did not proceed.
When selenoamide (1g) was employed for this reaction, the
corresponding aminocyclopropane was not obtained, but 1,4-
dicarbonyl compound (5gc) was formed in 56% yield (Scheme 1). It
was reported that aminocyclopropanes underwent hydrolysis to
form the corresponding 1,4-dicarbonyl compounds.13 Most proba-
bly due to the basic character of the pyridyl group, the generated
aminocyclopropane might undergo hydrolysis to provide 5gc.
The configuration of 4ec was determined by DIFNOE-NMR ex-
periments (Fig. 1). NOE was observed between Ha and both Hb and
o-H of aryl group. Therefore, it is suggested that the piperidyl group
holds a Z-position to the ester group.14
Table 1
Copper(0)-induced reaction of N-(selenobenzoyl)piperidine (1a) with several olefins
(3)a
Se
Cu(0) (4 mmol)
+
olefin
Ph
N
1a, 1 mmol
3, 1 mL
Ph
R
N
+
N
+
1a
Ph
N
Ph
2a
(recovered)
4
Entry
1
Olefin
Conditions
Yielda (%)
4
2a
1a
(94 ꢀC, 14 h)
d
56
44
3a
n
O Bu
2
3
(83 ꢀC, 7 h)
d
25
7
60
47
Next, we examined the reaction of selenoamide (1a) with
acrylonitrile (3i) in the presence of copper(0) (Eq. 6). When the
reaction was performed for 4 h, the corresponding amino-
cyclopropane carbonitrile (4ai) was obtained in 38% yield. In-
terestingly, the prolonged reaction time (14 h) resulted in the
formation of aminocyclopentane dicarbonitrile (6ai), along with
3b
3c
n
CO2 Bu
(100 ꢀC, 4 h)
4ac, 43
4
5
(110 ꢀC, 4 h)
(130 ꢀC, 4 h)
67 (66)
54
15
24
d
d
a
GLC (isolated) yield.

T. Mitamura et al. / Tetrahedron 64 (2008) 9983–9988
9985
Se
sequential insertion of 3i into aminocyclopropane (4ai) may take
place to give aminocyclopentane (6ai).
Cu(0) (4 mmol)
N
n
CO2 Bu
+
To clarify the stereoselectivity of the cyclopropanation, the
copper(0)-induced reaction of a selenoamide with maleate or fu-
marate was attempted. In the cases of maleates (3j and 3k), the
deselenative cyclopropanation proceeded with excellent stereo-
selectivity, to afford the corresponding aminocyclopropanes (4aj
and 4ak), where two ester groups were located with cis relation-
ship (Eq. 7).18
N
1g, 1 mmol
3c, 1 mL
n
CO2 Bu
N+
n
CO2 Bu
N
N
N
Se
CO2R
O
Ph
N
+
RO2C
H2O
n
CO2 Bu
1a, 1 mmol
3, 1 mL
R= Me (3j):
Et (3k):
N
5gc, 56%
*Isolated yield.
ð7Þ
RO2C
Ph
CO2R
Scheme 1. A plausible reaction pathway for the formation of 1,4-dicarbonyl compound
(5gc).
Cu(0) (4 mmol)
110 °C, 4 h
N
Hc
O
R=
Me (4aj): 62% (76%)
Et (4ak): 72% (83%)
*Isolated (GLC) yield.
n
CO2 Bu
n
N
O
Pr
C
H2
Ha
7.7%
Hb
H
N
2.1%
4.5%
Me
On the other hand, similar treatment of diethyl fumarate (3l)
provided a mixture of cis- and trans-isomers (4ak and 4al) (Eq. 8).
Moreover, the prolonged reaction time led to the isomerization to
give only the cis-isomer (4ak). This result suggests that the trans-
isomer may be an initial product, which gradually converts to the
corresponding cis-isomer.19
Me
Figure 1. DIFNOE-NMR experiment and configuration of aminocyclopropane (4ec).
aminocyclopropane (4ai).15 After the reaction was performed for
24 h, the reaction afforded 6ai with good selectivity.16
Se
Se
Cu(0) (4 mmol)
EtO2C
Cu(0) (4 mmol)
+
+
Ph
N
CO2Et
110 °C
Ph
N
CN
reflux
1a, 1 mmol
3l, 1 mL
CO2Et
1a, 1 mmol
3i, 1 mL
NC
EtO2C
Ph
EtO2C
Ph
CO2Et
CN
ð8Þ
CN
+
N
N
ð6Þ
+
Ph
N
Ph
N
4ak
4al
4ai
6ai
4 h
14 h
40%
59%
91%
4 h
ND
−
(38)%
26%
* GLC yield.
14 h
24 h
24%
9 (5) %
58 (24) %
* GLC (isolated) yield.
These aminocyclopropanation products are potentially useful
synthetic intermediates.20 For example, aminocyclopropanes can be
easily converted into 1,4-dicarbonyl compounds by acidic hydroly-
sis.13,21 1,4-Dicarbonyl compounds are useful key intermediates for
substituted cyclopentenones,22 such asjasmones and prostaglandins,
and for five-membered heterocyclic compounds,23 such as furans,
pyrroles, thiophenes, and pyridazines. Thus, we examined the hy-
drolysis of aminocyclopropanes to produce the corresponding 1,4-
dicarbonyl compounds. Treatmentoftheaminocyclopropanebearing
carbonyl group such as 4ac with 2 N HCl led to deaminative ring-
opening reaction to give the corresponding 1,4-dicarbonyl compound
(5ac) in 32% yield (Eq. 9). Similar conditions could be employed with
4ad, 4aj, and 4ak, and the corresponding 1,4-dicarbonyl products
5ad, 5aj, and 5ak were obtained in good yields, respectively.
These results suggest that the cyclopentanation reaction may
proceed via aminocyclopropane (4ai).17 A plausible reaction path-
way for this cyclopentanation reaction is indicated in Scheme 2:
CN
Se
(3i)
CN
Ph
N
Ph
4ai
N
Cu(0)
1a
NC
CN
Ph
N
R
R'
O
2 N HCl aq.
NC
NC
CN
Ph
N
Ph
R'
CN
R
ð9Þ
n
R = H, R' = CO2 Bu
Ph
N
Ph
N
4ac,
5ac, 32%
4ad, R = H, R' = CO2Me
4ak, R, R' = CO2Et
4aj, R, R' = CO2Me
5ad, 65%
5ak, 61%
5aj, 32%
6ai
Scheme 2. A plausible reaction pathway for the formation of aminocyclopentane (6ai).

9986
T. Mitamura et al. / Tetrahedron 64 (2008) 9983–9988
3. Conclusion
4.2.3. 2-Phenyl-2-piperidin-1-yl-cyclopropanecarboxylic acid ethyl
ester (4ae)
Yellow oil; 1H NMR (400 MHz, CDCl3)
In summary, we have described the copper(0)-induced cyclo-
propanation of several electron-deficient olefins (3) via deselena-
tion of selenoamides (1) to afford aminocyclopropanes (4).
Aminocyclopropanes can be easily converted to 1,4-dicarbonyl
compounds by treatment with 2 N HCl. Further studies on the
precise mechanism of this cyclopropanation is now in progress.
d
1.25 (t, J¼7.4 Hz, 3H),
1.39–1.72 (m, 6H), 2.12–2.48 (m, 5H), 2.53 (dd, J¼7.3, 7.8 Hz, 1H),
2.70 (dd, J¼7.3, 7.8 Hz, 1H), 4.14 (t, J¼7.3 Hz, 2H), 7.52 (t, J¼7.8 Hz,
2H), 7.67 (t, J¼7.3 Hz, 1H), 7.98 (d, J¼10.8 Hz, 2H); 13C NMR
(75 MHz, CDCl3)
d 14.2, 24.0, 25.7 (2C), 32.1 (2C), 54.1 (2C), 60.2,
124.9, 127.9, 129.0, 129.9, 133.0, 134.8, 172.6; IR (NaCl) 2963, 2936,
2840, 1732, 1672, 1597, 1448, 1211, 1175, 1159, 1113, 1024, 719, 687,
644 cmꢁ1; HRMS (EI) calcd for C17H23NO2 (Mþ): 273.1729, found
273.1723.
4. Experimental section
4.1. Synthesis of selenoamides, e.g., N-(selenobenzoyl)-
piperidine (1a)1b
4.2.4. 2-Phenyl-2-piperidin-1-yl-cyclopropanecarboxylic acid
tert-butyl ester (4af)
A stirred mixture of benzonitrile (1.2 mL, 11.8 mmol), selenium
(1.05 g, 13.1 mmol), H2O (2.4 mL, 133 mmol), Et3N (2.4 mL,
17.3 mmol), and THF (10 mL) in a 50 mL stainless steel autoclave
was heated under the pressure of CO (1.5 MPa: initial pressure at
25 ꢀC) at 110 ꢀC for overnight. After the reaction, CO was purged in
the well-ventilated hood, and to the reaction mixture was added
piperidine (2.0 mL, 19.7 mmol), and then the resulting mixture was
heated in an autoclave at 110 ꢀC for 4 h. After the reaction, the re-
action mixture was slightly acidified with aqueous 2 N HCl and
extracted with Et2O. The combined extracts were dried over MgSO4,
filtered, and evaporated. The crude material was purified by column
chromatography on silica gel affording 1.28 g (43%) of N-(seleno-
benzoyl)piperidine (1a) as a yellow crystal (mp 89 ꢀC).
A pale yellow oil; 1H NMR (400 MHz, CDCl3)
d 1.36–1.58 (br s,
13H), 1.57 (m, 3H), 2.23–2.52 (m, 5H), 2.63 (dd, J¼7.3, 7.8 Hz, 1H),
7.40–7.70 (m, 3H), 7.89–8.11 (m, 2H); 13C NMR (75 MHz, CDCl3)
d
24.2, 25.8, 28.0, 33.4, 52.8, 54.1, 54.3, 80.1, 127.8, 128.2, 128.8,
129.5, 130.8, 133.0, 172.0; IR (NaCl) 2934, 2853, 2777, 2739, 1730,
1638, 1443, 1367, 1354, 1302, 1273, 1252, 1150, 1113, 1072, 1032, 995,
849,756, 706 cmꢁ1; HRMS (CI) calcd for C19H28NO2 (Mþþ1):
302.2120, found 302.2115.
4.2.5. 1-(2-Phenyl-2-piperidin-1-yl-cyclopropyl)-ethanone (4ag)
A pale yellow oil; 1H NMR (400 MHz, CDCl3)
d 1.43 (br s, 2H),
1.50–1.80 (m, 4H), 2.16 (s, 3H), 2.29–2.54 (m, 2H), 2.56–2.77 (m,
3H), 2.77 (dd, J¼7.2, 8.0 Hz, 1H), 2.91 (dd, J¼6.8, 7.6 Hz, 1H), 7.21–
7.68 (m, 3H), 7.91–8.12 (m, 2H); 13C NMR (75 MHz, CDCl3) 24.0, 25.7,
30.1, 38.2, 41.2, 53.3, 53.7, 54.4, 125.6, 126.5, 128.3, 129.9, 130.5,
142.8, 199.4; IR (NaCl) 2936, 2855, 2804, 1713, 1668, 1614, 1450,
1360, 1306, 1117, 1028, 976, 700, 667, 644 cmꢁ1; HRMS (CI) calcd for
4.2. General procedure for copper(0)-induced
cyclopropanation of selenoamide with electron-deficient
olefins
C
16H22NO (Mþþ1): 244.1701, found 244.1700.
A
mixture of N-(selenobenzoyl)piperidine (1a, 253 mg,
1.0 mmol), diethyl maleate (3k, 1.0 mL, 7.0 mmol), and copper(0)
powder (252 mg, 4.0 mmol) was stirred at 110 ꢀC for 4 h under
nitrogen atmosphere. The reaction mixture was cooled to room
temperature and copper powder was filtered through a Celite pad,
and excess olefin was removed from the filtrate under reduced
pressure. Purification was performed by GPC, yielding 248 mg
(72%) of (Z)-3-phenyl-3-piperidin-1-yl-cyclopropane-1,2-dicarb-
oxylic acid diethyl ester (4ak). Then, 4ak afforded 135 mg (61%) of
2-benzoyl-succinic acid diethyl ester (5ak) after work up with
aqueous 2 N HCl.
4.2.6. N-(1,2-Diphenyl-cyclopropyl)piperidine (4ah)
A light yellow oil; 1H NMR (400 MHz, CDCl3)
1.16 (m, 2H), 1.26
(m, 4H), 1.38 (dd, J¼8.3, 1.0 Hz, 2H), 2.11 (m, 2H), 2.33 (t like, 3H),
7.14–7.32 (m, 8H), 7.45 (d, 2H); 13C NMR (100 MHz, CDCl3)
21.5,
24.4, 26.1, 32.0, 50.8, 55.8, 125.4, 126.9, 127.1, 127.5, 128.3, 130.5,
138.8; IR (NaCl) 3056, 3023, 2932, 2801,1601,1497,1443,1319,1247,
1118, 1032, 767, 748, 696 cmꢁ1; MS (FAB) m/z 278 (Mþþ1, 17).
d
d
4.2.7. 2-(N,N-Dimethylamino)-2-phenyl-cyclopropanecarboxylic
acid n-butyl ester (4dc)
Yellow oil; 1H NMR (400 MHz, CDCl3)
d
0.87 (t, J¼7.2 Hz, 3H),
4.2.1. 2-Phenyl-2-piperidin-1-yl-cyclopropanecarboxylic acid
1.24 (m, 2H), 1.50 (m, 2H), 1.92–2.15 (m, 1H), 2.16–2.21 (m, 6H),
2.41–2.51 (m, 1H), 3.21–3.27 (m, 1H), 4.02 (m, 2H), 7.24–7.46 (m,
n-butyl ester (4ac)
Yellow oil; 1H NMR (400 MHz, CDCl3)
1.33–1.52 (m, 6H), 1.57–1.71 (m, 6H), 2.42–2.53 (m, 3H), 2.55 (dd,
J¼7.3, 7.8 Hz, 1H), 2.73 (dd, J¼7.3, 7.8 Hz, 1H), 4.08 (t, J¼6.4 Hz, 2H),
7.31–7.71 (m, 4H), 7.95–8.09 (m, 1H); 13C NMR (75 MHz, CDCl3)
d
0.93 (t, J¼7.3 Hz, 3H),
5H); 13C NMR (100 MHz, CDCl3)
d 13.6, 19.0, 27.3, 30.5, 40.1, 49.9,
52.5, 64.4, 64.5, 127.5, 127.7, 127.9, 128.3, 128.5, 133.2, 174.8; IR
(NaCl) 2959, 2874, 2781, 1732, 1690, 1454, 1352, 1173, 1123, 1072,
1026, 758, 702 cmꢁ1; HRMS (FAB) calcd for C16H24NO2 (Mþþ1):
262.1807, found: 262.1816.
d
13.6, 19.1, 24.0, 25.5, 30.6, 31.8, 53.9, 54.0, 64.3, 126.7, 128.4, 129.0,
129.9, 132.9, 136.5, 172.6; IR (NaCl) 2936, 2856, 1732, 1672, 1597,
1448, 1379, 1275, 1211, 1175, 1113, 1072, 1028, 1028, 1001, 644 cmꢁ1
;
4.2.8. 2-Piperidin-1-yl-2-p-tolyl-cyclopropanecarboxylic acid
MS (EI) m/z 301 (Mþ, 5); HRMS (CI) calcd for C19H28NO2 (Mþþ1):
n-butyl ester (4ec)
302.2120, found 302.2126.
Yellow oil; 1H NMR (400 MHz, CDCl3)
1.29–1.50 (m, 4H), 1.56–1.76 (m, 6H), 2.16–2.49 (m, 8H), 2.53 (dd,
d
0.93 (t, J¼7.2 Hz, 3H),
4.2.2. 2-Phenyl-2-piperidin-1-yl-cyclopropanecarboxylic acid
J¼7.2, 7.6 Hz, 1H), 2.69 (dd, J¼6.8, 7.6 Hz, 1H), 4.10 (t like, 2H), 7.15–
methyl ester (4ad)
7.35 (m, 2H), 7.85–7.98 (m, 2H); 13C NMR (75 MHz, CDCl3)
d 13.6,
Yellow oil; 1H NMR (400 MHz, CDCl3)
d
1.26–1.36 (m, 2H), 1.41–
19.0, 24.1, 25.6, 30.5, 32.0, 54.1, 64.1, 126.8, 128.8, 129.5, 129.8, 130.5,
139.2,172.6; IR (NaCl) 2930, 2851, 2781,1736,1686,1508,1447,1377,
1.78 (m, 6H), 2.43 (m, 3H), 2.53 (dd, J¼6.8, 7.8 Hz, 1H), 2.68 (dd,
J¼6.8, 7.3 Hz,1H), 3.68 (s, 3H), 7.29–7.70 (m, 3H), 7.92–8.09 (m, 2H);
1230, 1184, 1173, 1151, 1113, 1032, 1001, 908, 853, 820, 733 cmꢁ1
HRMS (EI) calcd for C20H29NO2 (Mþ): 315.2198, found: 315.2205.
;
13C NMR (75 MHz, CDCl3)
d 24.2, 24.5, 25.8, 27.1, 31.9, 51.6, 54.1,
126.7, 128.3, 129.0, 130.0, 134.9, 136.4, 173.1; IR (NaCl) 2936, 2853,
2806, 1740, 1672, 1636, 1597, 1443, 1275, 1155, 1113, 1001, 854, 700,
644 cmꢁ1; MS (EI) m/z 259 (Mþ, 0.3); HRMS (EI) calcd for
4.2.9. 4-Oxo-4-pyridin-3-yl-butyric acid n-butyl ester (5gc)
Yellow oil; 1H NMR (400 MHz, CDCl3)
d
0.93 (t, J¼7.2 Hz, 3H),
C
16H21NO2 (Mþ): 259.1572, found 259.1554.
1.36 (m, 2H), 1.62 (m, 2H), 2.80 (t, J¼6.4 Hz, 2H), 3.33 (t, J¼6.4 Hz,

T. Mitamura et al. / Tetrahedron 64 (2008) 9983–9988
9987
2H), 4.11 (t, J¼6.6 Hz, 2H), 7.43 (m, 1H), 8.26 (d, J¼8.0 Hz, 1H), 8.80
(Mþ, 5); HRMS (CI) calcd for C14H19O3 (Mþþ1) 235.1334, found
(d, J¼3.2 Hz, 1H), 9.22 (s, 1H); 13C NMR (100 MHz, CDCl3)
d
13.6,
235.1338.
19.0, 27.9, 30.5, 33.5, 64.7, 123.6, 131.7, 135.2, 149.6, 153.6, 172.7,
197.1; IR (NaCl) 2961, 2934, 2874, 1732, 1693, 1585, 1420, 1315, 1171,
1069, 1026, 945, 704 cmꢁ1; HRMS (CI) calcd for C13H18NO3 (Mþþ1):
236.1286, found: 236.1290.
4.2.15. Methyl 3-benzoylpropionate (5ad)
A light yellow oil; 1H NMR (270 MHz, CDCl3)
d
2.77 (t, J¼6.6 Hz,
2H), 3.33 (t, J¼6.6 Hz, 2H), 3.71 (s, 3H), 7.39–8.01 (m, 5H); 13C NMR
(68 MHz, CDCl3)
d 28.0, 33.4, 51.8, 126.7, 128.0, 128.6, 133.2, 173.3,
4.2.10. 2-Phenyl-2-piperidin-1-yl-cyclopropane carbonitrile (4ai)
198.0; IR (NaCl) 2998, 2951, 2854, 1740, 1687, 1597, 1581, 1449, 1438,
A pale yellow oil; 1H NMR (400 MHz, CDCl3)
d
1.36–1.54 (m, 2H),
1357, 1221, 1168, 1002, 750, 692 cmꢁ1; MS (EI) m/z 192 (Mþ, 5).
1.58–1.81 (m, 6H), 2.39–2.45 (m, 3H), 2.51 (dd, J¼7.2, 7.2 Hz, 1H),
2.68 (dd, J¼7.2, 7.6 Hz, 1H), 7.52 (dd, J¼7.2, 8.0 Hz, 2H), 7.67 (dd,
J¼6.4, 7.2 Hz, 1H), 7.98 (d, J¼7.2 Hz, 2H); 13C NMR (100 MHz, CDCl3)
4.2.16. 2-Benzoyl-succinic acid diethyl ester (5ak)
A pale yellow oil; 1H NMR (270 MHz, CDCl3)
d
1.12–1.25 (m, 6H),
2.96–3.15 (m, 2H), 4.08–4.17 (m, 4H), 4.87 (t, J¼7.2 Hz, 1H), 7.45–
7.62 (m, 3H), 8.02–8.65 (m, 2H); 13C NMR (68 MHz, CDCl3)
13.7,
d
15.6, 24.0, 25.7, 31.2, 34.2, 54.0, 54.1, 110.9, 129.0, 129.9, 134.9,
139.4; IR (NaCl) 2936, 2853, 2808, 2775, 2739, 2249, 1470, 1448,
1354, 1277, 1211, 1157, 1117, 1043, 991, 862, 754, 669 cmꢁ1; MS (EI)
m/z 226 (Mþ, 20); HRMS (EI) calcd for C15H18N2 (Mþ): 226.1470,
found 226.1467.
d
13.9, 33.1, 49.4, 60.8, 61.6, 128.5, 128.7, 133.5, 135.8, 168.5, 171.0,
194.0; IR (NaCl) 2983, 1736, 1686, 1597, 1581, 1448, 1370, 1330, 1271,
1177, 1096, 1029, 951, 858, 741, 690 cmꢁ1; HRMS (EI) calcd for
C
15H18O5 (Mþ) 278.1154, found 278.1157.
4.2.11. 4-Phenyl-4-piperidin-1-yl-cyclopentane-1,3-dicarbonitrile
(6ai)
4.2.17. 2-Benzoyl-succinic acid dimethyl ester (5aj)
Yellow oil; 1H NMR (270 MHz, CDCl3)
3.00 (t, J¼6.4 Hz, 2H),
3.60 (s, 6H), 4.82 (t, J¼7.3 Hz, 1H), 7.39–7.55 (m, 3H), 7.95–7.98 (m,
2H); 13C NMR (68 MHz, CDCl3)
33.0, 49.2, 52.0, 52.7, 128.7, 128.8,
133.7, 135.7, 169.1, 171.6, 193.9; IR (NaCl) 2933, 2873, 1736, 1682,
1555, 1445, 1421, 1366, 1301, 1263, 1175, 1101, 1033, 1009, 919, 881,
768, 731, 704 cmꢁ1; HRMS (FAB) calcd for C13H15O5 (Mþþ1)
251.0919, found 251.0924.
A pale yellow oil; 1H NMR (400 MHz, CDCl3)
d
1.13–1.73 (m, 6H),
d
2.00–2.77 (m, 4H), 3.01 (dd, J¼3.6, 18.2 Hz, 1H), 3.16 (dd, J¼5.8,
17.4 Hz, 1H), 3.33 (dd, J¼9.6, 18.2 Hz, 1H), 3.47–3.66 (m, 1H), 3.80 (d,
J¼9.6 Hz, 1H), 4.00–4.17 (m, 1H), 7.13–8.19 (m, 5H); 13C NMR
d
(100 MHz, CDCl3) d 24.0, 24.4, 25.7, 26.0, 26.2, 28.8, 39.2, 60.5, 61.5,
71.1, 111.3, 126.4, 128.2, 128.4, 128.6, 128.7, 134.7; IR (NaCl) 3059,
2936, 2855, 2808, 2741, 2245, 1628, 1578, 1447, 1493, 1375, 1352,
1275, 1259, 1238, 1157, 1115, 1028, 1003, 854, 787, 754, 706,
642 cmꢁ1; MS (EI) m/z 279 (Mþ, 10); HRMS (EI) calcd for C18H21N3–
C3H3N (Mþꢁ53.0277): 226.1459, found 226.1467.
Acknowledgements
This work is supported by Grant-in-Aid for Scientific Research
on Priority Areas (Area 444, No. 19020061) and Scientific Research
(B, 19350095) from the Ministry of Education, Culture, Sports, Sci-
ence and Technology, Japan. We gratefully acknowledge emeritus
Prof. Noboru Sonoda (Osaka University) for his helpful suggestions.
We also thank Mr. Taizou Nanke, Mr. Noriaki Takami, and Dr.
Yukihito Sumino for their help at the initial stage of this work.
4.2.12. 3-Phenyl-3-piperidin-1-yl-cyclopropane-1,2-dicarboxylic
acid dimethyl ester (4aj)
A light yellow oil; 1H NMR (400 MHz, CDCl3)
d
1.41–1.82 (m, 6H),
2.98 (s, 2H), 3.00–3.14 (m, 4H), 3.61 (s, 3H), 3.72 (s, 3H), 7.03–7.43
(m, 5H); 13C NMR (75 MHz, CDCl3)
23.9, 26.8, 36.1, 36.9, 50.7,
d
51.4, 52.0, 94.8,127.8, 128.4,129.0,129.3,129.7,137.9, 163.5,167.5; IR
(NaCl) 3057, 2937, 2854, 1738, 1682, 1556, 1489, 1435, 1367, 1265,
1169, 1105, 1072, 1005, 953, 922, 770, 733, 667, 648 cmꢁ1; MS (EI)
m/z 317 (Mþ, 21); HRMS (FAB) calcd for C18H24NO4 (Mþþ1):
318.1705, found: 318.1700.
References and notes
1. (a) Ogawa, A.; Miyake, J.; Karasaki, Y.; Murai, S.; Sonoda, N. J. Org. Chem. 1985,
50, 384; (b) Ogawa, A.; Miyake, J.; Kambe, N.; Murai, S.; Sonoda, N. Bull. Chem.
Soc. Jpn. 1985, 58, 1448; (c) Segi, M.; Nakajima, T.; Suga, S.; Murai, S.; Ryu, I.;
Ogawa, A.; Sonoda, N. J. Am. Chem. Soc. 1988, 110, 1976; (d) Shimada, K.; Hikage,
S.; Takeishi, Y.; Takikawa, Y. Chem. Lett. 1990, 19, 1403; (e) Okuma, K.; Ikari, K.;
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mura, H.; Takikawa, Y. Chem. Lett. 1994, 23, 1743; (g) Shimada, K.; Jin, N.; Ka-
waguchi, M.; Dobashi, K.; Nagano, Y.; Fujimura, M.; Kudoh, E.; Kai, T.; Saito, N.;
Masuda, J.; Iwaya, M.; Fujisawa, H.; Aoyagi, S.; Takikawa, Y. Bull. Chem. Soc. Jpn.
1997, 70, 197; (h) Murai, T.; Ezaka, T.; Kato, S. Bull. Chem. Soc. Jpn. 1998, 71, 1193;
(i) Yoshifuji, M.; Higeta, N.; An, D.-L.; Toyota, K. Chem. Lett. 1998, 27, 17; (j)
Bhattacharyya, P.; Woollins, J. D. Tetrahedron Lett. 2001, 42, 5949; (k) Ishihara,
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ketsu, M.; Kanoh, M.; Itoh, E.; Ishihara, H. J. Org. Chem. 2001, 66, 4099; (m)
Koketsu, M.; Fukuta, Y.; Ishihara, H. J. Org. Chem. 2002, 67, 1008; (o) Ogawa, A.;
Sonoda, N. In Comprehensive Organic Synthesis; Trost, B. M., Ed.; Pergamon: New
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Current Chemistry; Wirth, T., Ed.; Springer: Berlin, 2000; Vol. 208, p 177.
2. For reactions of selenoamides, see: (a) Sekiguchi, M.; Ogawa, A.; Fujiwara, S.;
Ryu, I.; Kambe, N.; Sonoda, N. Chem. Lett. 1990, 19, 913; (b) Sekiguchi, M.;
Ogawa, A.; Fujiwara, S.; Ryu, I.; Kambe, N.; Sonoda, N. Chem. Lett. 1990, 19, 2053;
(c) Murai, T.; Ezaka, T.; Ichimiya, T.; Kato, S. Synlett 1997, 775; (d) Murai, T.;
Suzuki, A.; Ezaka, T.; Kato, S. Org. Lett. 2000, 2, 311; (e) Murai, T.; Fujishima, A.;
Iwamoto, C.; Kato, S. J. Org. Chem. 2003, 68, 7979; (f) Murai, T.; Nogawa, S.;
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4.2.13. 3-Phenyl-3-piperidin-1-yl-cyclopropane-1,2-dicarboxylic
acid diethyl ester (4ak)
A light yellow oil; 1H NMR (270 MHz, CDCl3) [Z-isomer]
d 1.11–
1.34 (m, 6H), 1.49–1.68 (m, 6H), 2.96 (s, 2H), 3.02 (t, J¼5.1 Hz, 4H),
4.08 (q, J¼7.3 Hz, 2H), 4.18 (q, J¼7.3 Hz, 2H), 7.28–7.40 (m, 5H); [E-
isomer]
d
1.00 (t, J¼7.3 Hz, 3H), 1.29 (t, J¼7.3 Hz, 3H), 1.36–1.55 (m,
6H), 2.25–2.55 (m, 4H), 2.83 (q, J¼9.2 Hz, 2H), 3.88 (q, J¼7.3 Hz, 2H),
4.10–4.30 (m, 2H), 7.15–7.50 (m, 5H); 13C NMR (68 MHz, CDCl3)
[Z-isomer]
d
14.2, 14.5, 24.0, 26.8, 26.9, 37.3, 52.1, 59.2, 60.0, 127.8,
13.8, 14.3,
128.4, 128.9, 129.6, 129.9, 138.1, 163.2, 167.1; [E-isomer]
d
24.1, 26.1, 34.0, 35.7, 50.9, 60.4, 60.8, 127.6, 127.8, 129.4, 129.7, 129.9,
132.7, 167.9, 168.9; IR (NaCl) 2979, 2934, 2854, 1736, 1682, 1555,
1445, 1421, 1366, 1301, 1263, 1175, 1101, 1033, 1009, 919, 881, 768,
731, 704 cmꢁ1; MS (EI) m/z 345 (Mþ, 18); HRMS (EI) calcd for
C
20H27NO4 (Mþ) 345.1940, found 345.1934.
4.2.14. n-Butyl 3-benzoylpropionate (5ac)
Yellow oil; 1H NMR (270 MHz, CDCl3)
d
0.92 (t, J¼7.6 Hz,
3H), 1.37 (m, 2H), 1.62 (m, 2H), 2.77 (t, J¼6.6 Hz, 2H), 3.31
(t, J¼6.61 Hz, 2H), 4.10 (t, J¼6.9 Hz, 2H), 7.44–7.57 (m, 3H), 7.97–
8.00 (m, 2H); 13C NMR (68 MHz, CDCl3)
d 13.7, 19.1, 28.2, 30.6,
33.4, 64.5, 128.0, 128.6, 133.1, 136.6, 172.9, 198.1; IR (NaCl) 2977,
2934, 2854, 1736, 1682, 1555, 1445, 1421, 1366, 1301, 1236, 1175,
1101, 1033, 1009, 919, 881, 768, 731, 704 cmꢁ1; MS (EI) m/z 234
3. Sekiguchi, M.; Ogawa, A.; Kambe, N.; Sonoda, N. Chem. Lett. 1991, 20, 315.

9988
T. Mitamura et al. / Tetrahedron 64 (2008) 9983–9988
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1997, 53, 12895.
9. In addition to the present aminocyclopropanation, we also observed desele-
native coupling reaction and N–H bond insertion reaction by using seleno-
amides in the presence of Cu(0). These results strongly suggest the possibility
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NMR experiments. It was suggested that aminocyclopropanes mainly formed Z-
configuration.
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determined by DIFNOE-NMR experiments.
of the intermediacy of
could not succeed the direct observation of
a
-aminocarbene or its related species. However, we
-aminocarbene species. The alter-
a
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with a Z-position to two ester groups.
native pathway may include the formation of radical anions from selenoamide
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´
´