Cyclopropane formation by nickel-catalysed electroreductive coupling of activated olefins and unactivated gem-dibromo compounds

Article abstract of DOI:10.1016/S0040-4020(01)01133-4

Cyclopropyl derivatives have been prepared with good yields by transition-metal catalysed electroreductive coupling of activated olefins and unactivated gem-dibromo compounds. This electrolysis is characterized by the use of a Fe/Ni catalyst system, acetonitrile as the solvent and a catalytic amount of triphenylphosphine as ligand. This procedure is a good alternative to the classical preparations of cyclopropyl derivatives from activated olefins (Simmons-Smith reaction, 1,3-dipolar addition of diazomethane, 1,4-addition of phosphorus and sulfur ylides).

Full text of DOI:10.1016/S0040-4020(01)01133-4

TETRAHEDRON
Pergamon
Tetrahedron 58 (2002) 271±277
Cyclopropane formation by nickel-catalysed electroreductive
coupling of activated ole®ns and unactivated
gem-dibromo compounds
p
Stephane Sengmany, Eric Leonel, Jean Paul Paugam and Jean-Yves Nedelec
Â
Â
 Â
Á Â
Laboratoire d'Electrochimie, Catalyse et Synthese Organique, UMR CNRS 7582, CNRS-Universite Paris XII, 2, Rue Henri Dunant,
B.P. 28, F-94320 Thiais, France
Received 17 July 2001; revised 17 October 2001; accepted 12 November 2001
AbstractÐCyclopropyl derivatives have been prepared with good yields by transition-metal catalysed electroreductive coupling of
activated ole®ns and unactivated gem-dibromo compounds. This electrolysis is characterized by the use of a Fe/Ni catalyst system,
acetonitrile as the solvent and a catalytic amount of triphenylphosphine as ligand. This procedure is a good alternative to the classical
preparations of cyclopropyl derivatives from activated ole®ns (Simmons±Smith reaction, 1,3-dipolar addition of diazomethane, 1,4-addition
of phosphorus and sulfur ylides). q 2002 Elsevier Science Ltd. All rights reserved.
1. Introduction
D, E, F), the more negative the reduction potential of the
ole®n, the lower the cyclopropane yield.
We previously reported1,2 that cyclopropyl rings can be
formed with satisfactory yields by direct electroreductive
coupling of activated ole®ns and polyhalo compounds
(alkyl gem-dihalides or a,a,a-trichlorides) using an
aluminium rod as the sacri®cial anode (Eq. (1)). We also
found that this process (referred to, in this paper, as method
a) is ef®cient only when the ole®n is more easily reducible
than the organic halide.
Since direct electrosyntheses (i.e. method a) fail to produce
cyclopropane compounds when the activated ole®n is
reduced at a potential lower than for the gem-dihalo
compounds, we tried to ®nd an alternative allowing the
activation of alkyl gem-dihalides. This can be expected
from indirect electrolyses involving electrogenerated low-
valent transition metal species which would react readily
with the gem-dihalo compounds. The approach reported
here is based on the use of nickel salts or complexes already
applied to the arylation, alkenylation, and alkylation of acti-
vated ole®ns.3 The nickel species can be either introduced
before the electrolysis (method b1),3 or generated in situ by
oxidation of Ni- or Fe/Ni-anode (method b2). We may
expect from this approach the formation of either a a-halo-
genated alkyl-nickel species or a nickel carbene. Would the
latter intermediate be formed, a concerted cycloaddition
may occur, which can eventually be evidenced from an
unsaturated substrate with a suitable con®guration about
the original double bond.
ꢀ1†
It has therefore come out that the ring formation likely
occurs through two nucleophilic displacements between
the reduced forms of the ole®n and the gem-alkyldihalide
in a non-concerted process. As a consequence, the most
stable compound is mainly formed, i.e. for example
dimethyl trans-3,3-dimethylcyclopropane-1,2-dicarboxy-
late from dimethyl maleate and 2,2-dibromopropane. A
survey of the results, some of them having not yet been
published, obtained from typical reagents and using
method a are given in Table 1.
2. Results and discussion
It appears that, apart from the coupling between dimethyl
itaconate III and methyl trichloroacetate IV (Table 1,
entries A3), for each polyhalo compound (entries A, B, C,
The ®rst approach employing added nickel salts (method
b1)3 was conducted at 608C in an undivided cell using an
iron rod as the anode, and a nickel grid as the cathode; the
reactants in a 2.5/1 ole®n/gem-polyhalo compound ratio and
²
Keywords: carbenoids; cyclopropanecarboxylates; electro-organic
synthesis; organonickel reagents; ring closure.
the catalyst NiBr2´xH2O (ca. 20% vs the limiting reactant)
p
Corresponding author. Tel.: 11-49-78-11-27; fax: 11-49-78-11-48;
e-mail: leonel@givt-cnrs.fr
²
NiBr2´xH2O, from Aldrich, delivered as NiBr2´3H2O:98%.
0040±4020/02/$ - see front matter q 2002 Elsevier Science Ltd. All rights reserved.
PII: S0040-4020(01)01133-4

272
S. Sengmany et al. / Tetrahedron 58 (2002) 271±277
Table 1. Direct electrochemical coupling of activated ole®ns and polyhalo compounds (method a)
A
B
C
D
E
F
Entries
!
Isolated yield
Product Nr
Isolated yield
Product Nr
Isolated yield
Product Nr
Isolated yield
Product Nr
Isolated yield
Product Nr
Isolated yield
Product Nr
Halo compound
Reagent Nr
(Reduction potential (V/SCE)) !
Cl3CCO2CH3
IV
(21.6)
PhCCl3
V
(21.7)
CH2Br2
VI
(22.1)
(CH3)2CBr2
VII
(22.1)
PhCHCl2
VIII
(22.2)
CH3CHBr2
IX
(22.3)
#
Ole®na
Reagent Nr
(Reduction potential (V/SCE)) #
1
I
(21.45)
43%b
1
34%b
4
30%
7
60%b
10
25%b
13
35%b
16
2c
II
(21.6)
6%
8
24%
7
2d
5d
11d
14d
17d
20%b
1
16%b
4
34%b
10
10%b
13
30%b
16
3
III
(22.05)
53%
3
Traces
6
Traces
9
13%b
12
Traces
15
Traces
18
DMF (45 ml), NBu4Br (250 mg), NBu4I (125 mg), Iˆ0.1 A, an aluminium rod as the anode, a nickel foam as the cathode.
a
EˆCO2Me.
b
See Ref. 2.
trans Cyclopropanes are identi®ed by comparison with spectral data of entry 1.
No (1r,2c) isomer was detected by GC.
c
d
Table 2. Indirect electrochemical coupling of activated ole®ns and polyhalo compounds catalysed by added nickel salts (method b1)
Entry
1
Ole®n
Polyhalo compound
Results
R1ˆR2ˆH, R3ˆCO2CH3. I
Cl3CCO2CH3: IV
Reduction of trichloromethylacetate and no coupling for the three ole®ns:
I, II, III
2
3
4
R1ˆCO2CH3, R2ˆR3ˆH. II
Cl3CCO2CH3: IV
Cl3CCO2CH3: IV
PhCCl3: V
R1ˆR3ˆH, R2ˆCH2CO2CH3. III
I
Reduction and dimerisation of PhCCl3 followed by reduction to
dichlorostilbene for the three ole®ns: I, II, III
5
6
7
8
II
III
I
II
III
I
II
III
I
PhCCl3: V
PhCCl3: V
CH2Br2: VI
CH2Br2: VI
CH2Br2: VI
(CH3)2CBr2: VII
(CH3)2CBr2: VII
(CH3)2CBr2: VII
PhCHCl2: VIII
No detectable reaction by GC for the three ole®ns: I, II, III
9
10
11
12
13
10: 45%
11: 4%, 10: 17%, (20/80: (cis/trans))
12: 44%
Essentially dimerisation of benzalchloride and reduction to stilbene for
the three ole®ns: I, II, III
14
15
16
II
III
I
PhCHCl2: VIII
PhCHCl2: VIII
CH3CHBr2: IX
16: 27% (24% of dimethyl 2-ethylidenebutane-1,4-dioate was also
isolated and characterized by MS)
17
18
II
CH3CHBr2: IX
CH3CHBr2: IX
17: Traces (1a,2a,3b (17a)/1a,2a,3a (17b)), 16: 20% (9% of dimethyl 2-
ethylidenebutane-1,4-dioate was also isolated and characterized by MS)
18: 45%
III

S. Sengmany et al. / Tetrahedron 58 (2002) 271±277
273
Table 3. Investigations on nickel-catalysed electroreductive coupling of dimethyl maleate and dibromomethane
Entry
Anode
SolventÐCH2Br2/
maleate, ligand
NiBr2´xH2O (%)
Temperature (8C)
Yield (%) 817
Stereoselectivity (cis/trans)
1a
2Fe
3
4
5
6
7
8
9
Fe
DMF/Pyb-1/2.5, no ligand
b-1/2.5, no ligand
20
20
20
50
50
50
50
0
60
60
60
60
RT
RT
60
0
Heterogeneous mixture
11
±
±
ACN/Py
Fe
Fe
Fe
Fe
Fe
Ni
ACN-1/2.5, no ligand
ACN-1/2.5, no ligand
ACN-1/2.5, no ligand
ACN-4/1, no ligand
ACN-4/1, no ligand
ACN-4/1, no ligand
ACN-4/1, no ligand
ACN-4/1, no ligand
ACN-4/1, PPh3
90/10
85/15
94/6
75/25
77/23
21
50
65
50
Traces
46
65
RT
RT
RT
RT
RT
RT
RT
Anodic passivation
43/57
75/25
Stainless steel
Fe/Ni 64/36
Fe/Ni 64/36
0
0
0
10
11c
77
80/20
12Fe/Ni 64/36
13
14
ACN-4/1, Bpy
0
0
0
60
84/16
Fe/Ni 64/36
Fe/Ni 64/36
ACN-4/1, DPA
ACN-4/1, DME
59
7286/14
88/12
a
The reaction conditions used in entry 1 are referred to as method b1.
90/10 (v/v).
The reaction conditions used in entry 11 are referred to as method b2.
b
c
were dissolved in a 90/10 (V/V) dimethylformamide
(DMF)/pyridine (Py) mixture, and the reactions were run
under constant current intensity (0.1 A). During the
electrolysis the working-electrode potential was near
21.2 V/SCE (Eq. (2)). Results are shown in Table 2.
from dimethyl maleate we obtained the two stereoisomers in
only 20/80 cis/trans ratio (11, 10), (Table 2, entry 11).
When CH2Br2 (VI) is used (Table 2, entries 7±9), no
product is formed from any ole®n. An hypothetical reaction
between a carbenoid species and DMF can been considered,
by analogy to what was observed in the reduction of CCl4 or
CF2Br2 in DMF.4a,b Therefore, we replaced DMF by aceto-
nitrile (ACN) as the solvent, and we investigated again the
cyclocondensation between dimethyl maleate and dibromo-
methane with the aim of improving both the yield and the
stereoselectivity (Eq. (3)). The results are reported in
Table 3.
ꢀ2†
The most interesting result is that cyclopropanes can be
obtained in good yields from alkyl-gem-dibromides, even
when the reduction potential of the halo compound is close
to the reduction potential of the ole®n (12: 44% and 18:
45%), (Table 2, entries 12 and 18). On the contrary, acti-
vated polychloro compounds are either reduced (IV, V,
VIII), (Table 2, entries 1±6 and entries 13±15) and/or
dimerised (V and VIII), (Table 2, entries 3±5 and 13±15)
under these reaction conditions. Also, the stereoselectivity
of the cyclopropanation is not much improved since starting
ꢀ3†
We ®rst found (Table 3, entries 2, 3) that nickel salts are not
very soluble in ACN/pyridine mixture, but more soluble in
ACN alone. We next studied the effect of the amount of
Table 4. Indirect electrochemical coupling of activated ole®ns and polyhalo compounds catalysed by electrogenerated nickel salts (method b2)
Entry
1
Ole®n
Polyhalo compound
Results
R1ˆR2ˆH, R3ˆCO2CH3. I
Cl3CCO2CH3: IV
Reduction of trichloromethylacetate and no coupling for the three
ole®ns: I, II, III
2
3
4
R1ˆCO2CH3, R2ˆR3ˆH. II
Cl3CCO2CH3: IV
Cl3CCO2CH3: IV
PhCCl3: V
R1ˆR3ˆH, R2ˆCH2CO2CH3. III
I
Reduction and dimerisation of PhCCl3 followed by reduction to
dichlorostilbene for the three ole®ns: I, II, III
5
6
7
8
II
III
I
II
III
I
II
III
I
PhCCl3: V
PhCCl3: V
CH2Br2: VI
CH2Br2: VI
CH2Br2: VI
(CH3)2CBr2: VII
(CH3)2CBr2: VII
(CH3)2CBr2: VII
PhCHCl2: VIII
7: 56%
8: 62%, 7: 15%, (80/20 (cis/trans))
9: 90%
10: 45%
11: 16%, 10: 16%, (50/50: (cis/trans))
12: 65%
Essentially dimerisation of benzalchloride and reduction to
stilbene for the three ole®ns: I, II, III
9
10
11
12
13
14
15
16
17
18
II
III
I
II
III
PhCHCl2: VIII
PhCHCl2: VIII
CH3CHBr2: IX
CH3CHBr2: IX
CH3CHBr2: IX
16: 50%
17: 30% 33/67 (1a,2a,3b (17a)/1a,2a,3a (17b)), 16: 2 8%
18: 30%

274
S. Sengmany et al. / Tetrahedron 58 (2002) 271±277
NiBr2 (Table 3, entries 3, 4), of the temperature (Table 3,
entries 4, 5), and of the dibromomethane/dimethyl maleate
ratio (Table 3, entries 5, 6). The best experimental condi-
tions we found are given at entry 6 (Table 3). This result
indicates that large amounts of nickel salts and a room
temperature are notably needed to obtain satisfactory yield
and selectivity. However, these two conditions can be
hardly simultaneously met due to the low solubility of
nickel salts at room temperature in ACN; this can only be
overcome by heating the mixture at 608C until an homo-
geneous medium is obtained, the yield then falls down to
50% with a similar stereoselectivity 77/23 (Table 3, entry
7). For that reason, we thought of generating Ni(II) by
anodic oxidation of a nickel-containing electrode. With a
nickel rod as the anode, however, we did not observe any
cyclopropanation, but polymerization occurred at the
surface of the anode (Table 3, entry 8). Interestingly, results
identical to those reported in Table 3 entry 6, combining
added nickel salts and an iron anode, were obtained with a
Fe/Ni (64/36) anode (Table 3, entry 10). This clearly indi-
cates that the presence of iron salts in the reaction medium is
a key factor, but which may possibly be masked by the
presence of chromium, when a stainless steel anode is
used (Table 3, entry 9). under these reaction conditions
(Table 3, entry 10), we examined the effect of various
ligands on the yield and the stereoselectivity (Table 3,
entries 11±14). The best yield was obtained with triphenyl-
phosphine (Table 3, entry 11), and the highest stereo-
selectivity with dipyridylamine, at the expense however of
the yield (Table 3, entry 13). The reaction conditions given
at entry 11 (Table 3), and referred to as method b2, have
then been applied to the coupling between various activated
Table 5. Ring formation by indirect electroreductive coupling of activated ole®ns and alkyl gem-dibromo compounds
Entry
Ole®na
E (V/SCE)
Polyhalo
compound
E (V/SCE)
Product [CAS RN]
Nr
Isolated yield%, methodb
1
2
21.45
CH2Br2
22.1
7
56, b2
21.6
CH2Br2
CH2Br2
22.1
8
62( 8), 15 (7) (80 cis/20 trans), b2
3
4
5
22.05
21.45
21.6
22.1
22.1
22.1
9
90, b2
60, a
(CH3)2CBr2
(CH3)2CBr2
10
11
16 (11), 16 (10) (50 cis/50 trans), b2
6
7
22.05
21.45
(CH3)2CBr2
22.1
22.3
12
16
65, b2
50, b2
CH3CHBr2
8
21.6
CH3CHBr2
22.3
22.3
17
18
30 (17), 33 (17a)/67 (17b), 28 (16), b2
9
22.05
CH3CHBr2
45, b1
a
EˆCO2CH3.
b
For typical procedure see Sections 4.2.1±4.2.3.

S. Sengmany et al. / Tetrahedron 58 (2002) 271±277
275
ole®ns and various polyhalo compounds (Eq. (4)). The
results for the different polyhalides IV±IX are reported in
Table 4.
chloride), and we are now searching for another metallic
system enabling the indirect activation of this type of
polyhalo compounds.
ꢀ4†
4. Experimental
4.1. General information
Thus the nickel-catalysed electroreductive coupling (i.e.
method b2) is ef®cient in the presence of activated ole®ns
and non-activated polyhalo compounds, no matter what
their relative reduction potentials are. However, the
previous nickel catalysed electroreductive process in
DMF/pyridine (method b1) is more ef®cient with the couple
IX/III to give cyclopropane 18 (Table 4, entry 18 and Table
2, entry 18), and, more surprisingly, these two nickel
catalysed processes fail with activated polychloro
compounds (Cl3CCO2Me, PhCCl3, PhCHCl2), (Table 4,
entries 1±6 and entries 13±15).
Melting point were determined with an Electrothermal IA
1
9100 digital melting point apparatus. H, 13C NMR spectra
were recorded on a Bruker AC-200 (200 MHz, 50 MHz,
respectively) or Bruker AM-300 (300 MHz, 75 MHz,
respectively) spectrometer. Mass spectra (electron impact)
were obtained on a GCQ Thermoquest spectrometer
coupled to a Finigan-GCQ with a DB 5MS capillary
column. High-resolution mass spectral analyses and
elemental analyses were carried out at `Service Central
d'Analyse du CNRS', Vernaison, France. Gas chromato-
graphy was performed on a Varian 3300 chromatograph
®tted with a SIL-5 CP capillary column. Solvents and
chemicals were used as received without further puri®ca-
tion.
These nickel-catalysed electrochemical methods can be
related to the work described by Kanai et al.,5a,b in which
zinc powder is used in large excess (3 equiv.) as the
reductant (yields obtained are: 7: 78%;5b 817: 78% (91/9,
cis/trans);5b 10: 44%;5b 11110: 39% (87/13, cis/trans);5b
16: 58%5b). Kanai has suggested that the nickel-catalysed
cyclopropanation proceeds via the formation of a metalla-
cyclobutane complex formed from a metallocarbene and the
ole®n. Our approach may be in keeping with such an analy-
sis on the basis of the good stereoselectivity in the formation
of 8 and 7 from dimethyl maleate and CH2Br2 in a cis/trans
ratio of 4:1.
4.2. General procedure
4.2.1. Method a, direct electrolysis with aluminium
anode. The reactions were conducted in an undivided cell
®tted with an aluminium rod as anode and a nickel foam as
cathode (area: ca. 40 cm2). A solution of the activated ole®n
(10 mmol), polyhalo compound (20 mmol) in DMF (45 ml)
containing Nbu4Br (250 mg) and NBu4I (125 mg) was
electrolysed at constant intensity (0.1 A) at room tempera-
ture until complete ole®n consumption. The reaction
mixture was poured into a cold mixture of 1 M HCl
(50 ml) and diethyl ether (50 ml). The layers were separated
and extracted with diethyl ether (3 portions of 25 ml). The
combined ethereal extracts were washed with brine, dried
over Na2SO4 and evaporated. Products were isolated by
column chromatography on silica gel (230±400 mesh)
using pentane/ether as eluent.
Our nickel-catalysed electrochemical method is an alter-
native to the Simmons±Smith reaction (CH2I2, Zn±Cu)6a
(9: 72%),6b the 1,3-dipolar addition of diazomethane to
activated ole®ns followed by thermolysis or photolysis (7:
33%,7a 9: 80%7b), the use of phosphorus ylides or diphenyl-
sulfonium isopropylide with conjugated carbonyl
compounds8a,b (10: 82%),8b the McCoy reaction9a,b (8:
39%,9b 7: 19%9b), the intramolecular oxidative coupling of
the bis-enolate derived from dimethylglutarates10a,b
(11110: 81%, 80/20 cis/trans,10a 17a: 75%10b), and the
electrochemical 1,3-debromination reaction of dimethyl
2,4-dibromopentanedioate11 (718: 75%, 70/30 trans/cis).
4.2.2. Method b1, indirect electrolysis with iron anode
and added nickel salts. The reactions were conducted in an
undivided cell ®tted with XC10 iron rod as anode and a
nickel foam as cathode (area: ca. 40 cm2). A solution of
the activated ole®n (25 mmol) and polyhalo compound
(10 mmol) in DMF/pyridine (45 ml/5 ml) containing
NiBr2´xH2O (436 mg), NBu4Br (250 mg) and NBu4I
(125 mg) was electrolysed at constant intensity (0.1 A) at
608C until complete consumption of the limiting reagent.
The products were isolated using the procedure described in
method a.
We have summarized in Table 5 our best results for the
electroreductive coupling of activated ole®ns and
unactivated polyhalo compounds.
3. Conclusion
We have developed a successful electrochemical cyclo-
propanation of activated ole®ns from alkyl gem-dibromo
compounds. This one step process is characterized by the
use of a Fe/Ni catalyst system, ACN as solvent, and tri-
phenylphosphine as ligand, and does not require the
preparation of reactive intermediates. The yields compare
favorably to those reported in the literature, and the stereo-
selectivity is moderately good. Very surprisingly, this
procedure fails with activated polychloro compounds
(a,a,a-trichlorotoluene, methyltrichloroacetate, benzal-
4.2.3. Method b2, indirect electrolysis with iron/nickel
64/36 anode. The reactions were conducted in an undivided
cell ®tted with an Fe/Ni 64/36 rod as anode and a nickel
foam as cathode (area: ca. 40 cm2). A solution of the acti-
vated ole®n (10 mmol), polyhalo compound (40 mmol) and
PPh3 (1 mmol) in acetonitrile (45 ml) containing NBu4Br
(250 mg) and NBu4I (125 mg) was electrolysed at constant
intensity (0.1 A) and at room temperature until complete

276
S. Sengmany et al. / Tetrahedron 58 (2002) 271±277
consumption of the limiting reagent. The products were
isolated using the procedure described in method a.
3H, s), 3.59 (OCH3, 3H, s), 2.50 (H-4, 2H, s), 1.30 (H-1b and
H-2b, 2H, m) 0.80 (H-1a and H-2a, 2H, m); 13C NMR
(50 MHz, CDCl3) d CO: 174.3, 171.7; OCH3: 51.7, 51.3;
C-4: 38.1; C-1: 19.8; C-2, C-3: 15.2; EI-MS m/z 172, 157,
141, 113 (base peak), 81, 59, 53; IR7b n cm21 (CCl4) 1740,
1735.
4.3. Isolated products
4.3.1. Dimethyl 1-chloro-2-methoxycarbonylmethyl-
cyclopropane-1,2-dicarboxylate 3 (new compound).
(C10H13ClO6); MW: 264.5; FAB-HR-MS calcd for
4.3.5. Dimethyl trans-3,3-dimethylcyclopropane-1,2-di-
carboxylate 10. (C9H14O4); MW: 186; CAS RN: 16601-
23-3. Pentane/ether: 90/10; obtained: 1.12 g (60% yield,
C10H14ClO6 (M1H)1 m/z 265.0479, found 265.0476.
1
method a); liquid. H NMR10a (200 MHz, CDCl3) d 3.7
Anal. Calcd for (1Rp2Rp) C10H13ClO6: C, 45.38; H, 4.95; O,
36.27; Cl, 13.40. Found: C, 45.33; H, 5.00; O, 36.51; Cl,
13.23. Anal. Calcd for (1Rp2Sp) C10H13ClO6: C, 45.38; H,
4.95; O, 36.27; Cl, 13.40. Found: C, 45.58; H, 5.08; O,
36.27; Cl, 13.64.
(OCH3, 6H, s), 2.20 (H-1 and H-2, 2H, s), 1.20 (H-4 and
H-5, 6H, s); 13C NMR (50 MHz, CDCl3) d CO: 170.1;
OCH3: 51.2; C-1, C-2: 33; C-3: 29.7; C-4, C-5: 19.8;
EI-MS m/z 186, 155, 127 (base peak), 95, 67; IR n cm21
(CCl4) 1735.
Pentane/ether: (95/5)±(80/20); obtained: 1.4 g (yield: 53%,
method a); liquid; two diastereoisomers (1Rp2Rp) and
(1Rp2Sp) in ratio 70/30. (1Rp,2Rp) 1H NMR (200 MHz,
CDCl3) d 3.76 (OCH3, 3H, s), 3.70 (OCH3, 3H, s), 3.61
(OCH3, 3H, s), 3.00 (H-4, 1H, d, Jˆ17 Hz), 2.55 (H-4,
1H, d, Jˆ17 Hz), 2.20 (H-3, 1H, d, Jˆ6.8 Hz), 1.90 (H-3,
1H, d, Jˆ6.8 Hz), for the couple H-3 (Dn/Jˆ8.1 Hz AB
4.3.6. Dimethyl cis-3,3-dimethylcyclopropane-1,2-di-
carboxylate 11. (C9H14O4); MW: 186. CAS RN: 20315-
30-4. Pentane/ether: 90/10; obtained: 0.3 g (16% yield,
1
method b2); liquid. H NMR10b (200 MHz, CDCl3) d 3.68
(OCH3, 6H, s), 1.89 (H-1 and H-2, 2H, s), 1.40 (H-4, 3H, s),
1.25 (H-5, 3H, s); 13C NMR10b (50 MHz, CDCl3) d CO:
169.5; OCH3: 51.6; C-1, C-2: 31.8; C-5: 27.9; C-3: 26;
C-4: 15.5; EI-MS10b m/z 186, 155, 127 (base peak), 95,
85, 73, 67, 65, 59, 55, 53; IR10b n cm21 (CCl4) 1735.
1
system): E/E trans. (1Rp,2Sp) H NMR (200 MHz, CDCl3)
d 3.76 (OCH3, 3H, s), 3.70 (OCH3, 3H, s), 3.64 (OCH3, 3H,
s), 3.10 (H-4, 1H, d, Jˆ17.4 Hz), 2.70 (H-4, 1H, d,
Jˆ17.4 Hz), 2.36 (H-3, 1H, d, Jˆ7.2Hz), 1.41 (H-3, 1H,
d, Jˆ7.2Hz), for the couple H-3 ( Dn/Jˆ26.1 Hz AX
system): E/E cis. 13C NMR (50 MHz, CDCl3) d (mixture
of the two diastereoisomers, 1Rp2Rp,(1Rp2Sp)): CO: 170.4,
167.7, 167.3, (170.6, 169.4, 166.5); OCH3: 53.4, 52.4, 51.6,
(53.2, 53.1, 52.6); C-1: 44.7 (48.5); C-4: 36.4, (35.8); C-2:
33.8, (32.8); C-3: 25.5, (26.2). EI-MS m/z (1Rp,2Rp): 266,
264, 235, 234, 233, 232, 228, 205, 203, 202, 201, 200, 198,
197, 192, 191, 178, 175, 174, 173, 172, 171, 170, 169 (base
peak), 165, 146, 145. (1Rp,2Sp): 266, 265, 235, 234, 233,
232, 228, 205, 203, 202, 201, 200, 198, 197, 192, 191, 178,
175, 174, 173, 172, 171, 170, 169 (base peak), 165, 146,
145; IR n cm21 (CCl4) 1760±1720.
4.3.7. Methyl 2,2-dimethyl-1-methoxycarbonylmethyl-
cyclopropane-1-carboxylate 12. (C10H16O4); MW: 200.
CAS RN: 205320-55-4. Pentane/ether: 90/10; obtained:
1.3 g (65% yield, method b2); liquid. 1H NMR2
(200 MHz, CDCl3) d 3.46 (OCH3, 3H, s), 3.45 (OCH3,
2
3H, s), 2.83 (H-6, 1H, d, Jˆ17.3 Hz), 2.15 (H-6, 1H, d,
2
2Jˆ17.3 Hz), 1.3 (H-3, 1H, d, Jˆ5 Hz), 1.00±0.96 (H-4
2
and H-5, 6H, 2s), 0.4 (H-3, 1H, d, Jˆ5 Hz); 13C NMR2
(50 MHz, CDCl3) d CO: 172.7, 171.9; OCH3: 51.1, 51;
C-6: 35.7; C-1: 30; C-3: 25.5; C-2: 24.5; C-4, C-5: 22, 20;
EI-MS2 m/z 200, 169, 168, 140, 125, 109, 81 (base peak),
79, 53; IR2 n cm21 (CCl4) 1735.
4.3.8.
Dimethyl
carboxylate 16. (C8H12O4); MW: 172; CAS RN: 28363-
3-methylcyclopropane-1a,2b-di-
4.3.2. Dimethyl trans-cyclopropane-1,2-dicarboxylate 7.
(C7H10O4); MW: 158; CAS RN: 826-35-7. Pentane/ether:
1
79-3. Pentane/ether: 95/5; obtained: 0.85 g (50% yield,
80/20; obtained: 0.89 g (56% yield, method b2); liquid. H
method b2); liquid. H NMR5b (200 MHz, CDCl3) d 3.63
(OCH3, 3H, s), 3.62(OCH , 3H, s), 2.25 (H-1, 1H, dd,
1
NMR9b (200 MHz, CDCl3) d 3.7 (OCH3, 6H, s), 2.20±2.10
(H-1 and H-2, 2H, m), 1.45±1.35 (H-3, 2H, m); 13C NMR9b
(50 MHz, CDCl3) d CO: 171.9; OCH3: 51.8; C-1, C-2: 21.9;
C-3: 15; EI-MS9b m/z 158, 127, 126, 99, 98 (base peak), 83,
71, 68, 59, 55; IR9b n cm21 (CCl4) 1735.
3
3Jˆ9.5, 4.8 Hz), 2.04 (H-2, 1H, dd, Jˆ5.8, 4.8 Hz), 1.79
3
(H-3, 1H, m), 1.20 (H-4, 3H, d, Jˆ6 Hz); 13C NMR5b
3
(50 MHz, CDCl3) d CO: 172.3, 170.3; OCH3: 51.9, 51.6;
C-1, C-2: 28.2, 27.7; C-3: 23.7; C-4: 11; EI-MS m/z 141,
113 (base peak), 81, 59, 53; IR n cm21 (CCl4) 1735.
4.3.3. Dimethyl cis-cyclopropane-1,2-dicarboxylate 8.
(C7H10O4); MW: 158; CAS RN: 826-34-6. Pentane/ether:
1
4.3.9.
carboxylate 17a. (C8H12O4); MW: 172; CAS RN: 14661-
Dimethyl
3b-methylcyclopropane-1a,2a-di-
80/20; obtained: 0.98 g (62% yield, method b2); liquid. H
NMR10b (200 MHz, CDCl3) d 3.40 (OCH3, 6H, s), 1.90 (H-1
and H-2, 2H, dd, Jˆ8.4, 6.7 Hz), 1.40 (H-3a, 1H, td, Jˆ6.7,
4.9 Hz), 1.00 (H-3b, 1H, td, Jˆ8.4, 4.9 Hz); 13C NMR10b
(50 MHz, CDCl3) dCO: 170.2; OCH3: 51.9; C-1, C-2:
21.2; C-3: 11.6; EI-MS m/z 158, 127 (base peak), 99, 71;
IR n cm21 (CCl4) 1735.
79-1. Pentane/ether: 90/10; obtained: 0.172g (10% yield,
method b2); liquid. H NMR10b (200 MHz, CDCl3) d 3.60
1
(OCH3, 6H, s), 1.95 (H-3, 1H, m), 1.76 (H-1, H-2, 2H, d,
3Jˆ6.1 Hz), 1.1 (H-4, 3H, d, 3Jˆ6 Hz); 13C NMR10b
(50 MHz, CDCl3) d CO: 169.9; OCH3: 51.7; C-1, C-2:
28.9; C-3: 20.3; C-4: 16.4; EI-MS10b m/z 172, 141, 113
(base peak), 85, 81, 71, 59, 53; IR10b n cm21 (CCl4) 1735.
4.3.4. Methyl 1-methoxycarbonylmethylcyclopropane-1-
carboxylate 9. (C8H12O4); MW: 172; CAS RN: 6081-67-0.
Pentane/ether: 80/20; obtained: 1.55 g (90% yield, method
4.3.10. Dimethyl 3a-methylcyclopropane-1a,2a-di-
carboxylate 17b. (C8H12O4); MW: 172; CAS RN:
1
b2); liquid. H NMR7b (200 MHz, CDCl3) d 3.63 (OCH3,

S. Sengmany et al. / Tetrahedron 58 (2002) 271±277
277
J. Org. Chem. 1990, 55, 2503±2507. (b) Lachaise, I.; Lu,
87421-39-4. Pentane/ether: 90/10; obtained: 0.345 g (20%
yield, method b2); liquid. H NMR (200 MHz, CDCl3) d
1
 Â
Y.-W.; Nedelec, J.-Y.; Perichon, J. Res. Chem. Interm. 1991,
Â
3.38 (OCH3, 6H, s), 1.80 (H-1, H-2, 2H, d, 3Jˆ8.8 Hz), 1.35
15, 253±260.
  Â
2 . Loenel, E.; Paugam, J. P.; Condon-Gueugnot, S.; Nedelec,
3
(H-3, 1H, m), 1.06 (H-4, 3H, d, Jˆ6.5 Hz); 13C NMR5b
J.-Y. Tetrahedron 1998, 54, 3207±3218.
  Â
3. Condon-Gueugnot, S.; Leonel, E.; Nedelec, J.-Y.; Perichon, J.
(50 MHz, CDCl3) d CO: 169.1; OCH3: 51.3; C-1, C-2:
23.7, 23.6; C-3: 18.7; C-4: 8.1; EI-MS m/z 172, 141, 140,
113 (base peak), 112, 85, 81, 71, 53; IR n cm21 (CCl4) 1735.
Â
J. Org. Chem. 1995, 60, 7684±7686.
Â
 Â
4. (a) Leonel, E.; Paugam, J. P.; Heintz, M.; Nedelec, J.-Y. Synth.
Commun. 1999, 29, 4015±4024. (b) Burton, D. J.; Wiemers,
D. M. J. Am. Chem. Soc. 1985, 107, 5014±5015.
4.3.11. Methyl 2-methyl-1-methoxycarbonylmethyl-
cyclopropane-1-carboxylate 18 (new compound).
(C9H14O4); MW: 186; FAB-HR-MS calcd for C9H14O4
(M1Li)1 m/z 193.1052, found 193.1038. Pentane/ether:
90/10; obtained: 0,84 g (two diastereoisomers RpRp and
RpSp: 50±50; 45% yield, method b1); liquid.
È
5. (a) Kanaõ, H.; Hiraki, N.; Iida, S. Bull. Chem. Soc. Jpn 1983,
56, 1025±1029. (b) Kanaõ, H.; Nishiguchi, Y.; Matsuda, H.
È
Bull. Chem. Soc. Jpn 1983, 56, 1592±1597.
6. (a) Simmons, H. E.; Smith, R. D. J. Am. Chem. Soc. 1959, 81,
4256±4264. (b) Simmons, H. E.; Cairns, T. L.; Vladuchick,
S. A.; Hoiness, C. M. Organic Reactions, Vol. 20; Wiley: New
York, 1973; pp 1±131.
1H NMR (200 MHz, CDCl3) d 3.67 (OCH3, 6H, s), 2.90
(H-4, 1H, d, 2Jˆ17 Hz), 2.20 (H-4, 1H, d, 2Jˆ17 Hz),
1.30-0.90 (H-2and H-3, 3H, m), 1.2(CH 3, 3H, d,
Jˆ1.6 Hz); 13C NMR (50 MHz, CDCl3) d CO: 172.2,
172; OCH3: 51.5, 51.3, C-4: 40, C-1: 25.6, C-2: 23.1, C-3:
20.7; C-5: 12.3; EI-MS m/z 186, 155, 154, 127, 126, 111, 95,
94, 67 (base peak), 66, 65, 59, 53; IR n cm21 (CCl4) 1735.
7. (a) Von Auwers, K.; Konig, F. Liebigs Ann. Chem. 1932, 496,
252±282. (b) Hartmann, W.; Schrader, L.; Wendisch, D.
Chem. Ber. 1973, 106, 1076±1082.
8. (a) Devos, M. J.; Denis, J. N.; Krief, A. Tetrahedron Lett.
1978, 1847±1850. (b) Corey, E. J.; Jautelat, M. J. Am.
Chem. Soc. 1967, 89, 3912±3914.
1H NMR (200 MHz, CDCl3) d 3.69 (OCH3, 3H, s), 3.64
9. (a) McCoy, L. L. J. Am. Chem. Soc. 1958, 80, 6568±6572.
(b) Csuk, R.; Von Scholz, Y. Tetrahedron 1994, 50, 10431±
10442.
2
(OCH3, 3H, s) 2.70 (H-4, 1H, d, Jˆ17 Hz), 2.5 (H-4, 1H,
d, 2Jˆ17 Hz), 1.65 (H-2, 1H, m), 1.45 (H-3, 1H, dd,
3
3
2Jˆ4 Hz, Jˆ9 Hz) 1.1 (CH3, 3H, d, Jˆ6 Hz), 0.5 (H-3,
1H, dd, 2Jˆ4 Hz, 3Jˆ7 Hz); 13C NMR (50 MHz, CDCl3) d
CO: 174.8, 172.6; OCH3: 51.7, 51.4, C-4: 33.4, C-1: 24.2,
C-3: 22.4, C-2: 20.7; CH3: 13.6; EI-MS m/z 186, 171, 155,
154, 127, 126, 111, 95, 94, 85, 68, 67 (base peak), 66, 65, 59,
55, 54, 53; IR n cm21 (CCl4) 1735.
10. (a) Babler, J. H.; Haack, R. A. Synth. Commun. 1983, 13, 905±
911. (b) Walser, P.; Renold, P.; N'Goka, V.; Hosseinzadeh, F.;
Tamm, C. Helv. Chim. Acta 1991, 74, 1941±1952.
11. (a) Satoh, S.; Itoh, M.; Tokuda, M. J. Chem. Soc., Chem.
Commun. 1978, 481±482. (b) Tokuda, M.; Hayashi, A.;
Sugimone, H. Bull. Chem. Soc. Jpn 1991, 64, 2590±2592.
References
  Â
1. (a) Lu, Y.-W.; Nedelec, J.-Y.; Folest, J.-C.; Perichon, J.