Heterosubstituted cyclopropanation of alkenes with organochromium reagents derived from heterosubstituted dihalomethanes, CrCl2, and tetraalkylethylenediamine

Article abstract of DOI:10.1016/j.jorganchem.2006.06.047

Iodocyclopropanes of trans configuration are produced stereoselectively from terminal alkenes by treatment with a reagent derived from iodoform, chromium(II) chloride, and TEEDA (N,N,N′,N′-tetraethylethylenediamine) in THF. Similarly, cyclopropylsilanes a

Full text of DOI:10.1016/j.jorganchem.2006.06.047

Journal of Organometallic Chemistry 692 (2007) 520–529
www.elsevier.com/locate/jorganchem
Heterosubstituted cyclopropanation of alkenes with
organochromium reagents derived from heterosubstituted
dihalomethanes, CrCl , and tetraalkylethylenediamine
2
*
Kazuhiko Takai , Shota Toshikawa, Atsushi Inoue, Ryo Kokumai, Masato Hirano
Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan
Received 19 May 2006; received in revised form 8 June 2006; accepted 20 June 2006
Available online 3 September 2006
Abstract
Iodocyclopropanes of trans configuration are produced stereoselectively from terminal alkenes by treatment with a reagent derived
0
0
from iodoform, chromium(II) chloride, and TEEDA (N,N,N ,N -tetraethylethylenediamine) in THF. Similarly, cyclopropylsilanes
and cyclopropylboronic esters are obtained by using R SiCHI , and a combination of Cl CHB(OR) and LiI instead of iodoform,
3
2
2
2
respectively. The heterocyclopropanation occurs selectively at terminal double bonds, and di- and trisubstituted double bonds in the
same molecules remain unchanged. Such functional groups as alcohol, ether, silyl ether, ester, tertiary amine, and amide groups are com-
patible with the reaction conditions.
ꢀ
2006 Elsevier B.V. All rights reserved.
Keywords: Chromium(II); Cyclopropane; Cyclopropylsilane
1
. Introduction
direct-approach to heterosubstituted cyclopropanes is via
the heterocyclopropanation of alkenes due of the accessi-
bility of the starting materials [2]. However, this has not
been popular due to the lack of appropriate reagents for
simple terminal alkenes which satisfy both yield and stere-
oselective requirements. We have recently discovered the
iodocyclopropanation of terminal olefins with a reagent
derived from iodoform, chromium(II) chloride, and
Heterosubstituted cyclopropanes are useful building
blocks for constructing compounds having cyclopropane
rings [1–5]. For example, iodocyclopropanes [1,2] and
cyclopropylboronic esters [5,7] can be used in Suzuki–
Miyaura-type cross-coupling reactions to prepare the
cyclopropyl–cyclopropyl and –vinyl carbon skeletons of
natural products [6] such as FR-900848 and U-106305.
Heterosubstituted cyclopropanes are typically accessed
via Simmons–Smith cyclopropanation of the correspond-
ing heterosubstituted olefins [8]. Cyclopropanation with
zinc carbenoids, however, suffers from the low reactivity
of the olefins due to electron-deficiency by substitution of
halogen or boron atoms, or steric hindrance by substitu-
tion of trialkylsilyl groups. Therefore, it has been necessary
to bring the zinc carbenoid close to the olefinic double
bonds using oxygen functional groups [9,10]. An attractive
0
0
N,N,N ,N -tetraethylethylenediamine (TEEDA) [11a].
Also, cyclopropylsilanes [11b] and -boronic esters have
been prepared using a reagent derived from R SiCHX
3
2
and (RO) BCHCl instead of iodoform, respectively. These
2
2
methods will provide an alternative route to heterosubsti-
tuted cyclopropanes.
2. Results and discussion
Iodocyclopropanation [11a]. Treatment of allyl benzyl
ether (1) with a mixture of iodoform (2 equiv.) and chro-
mium(II) chloride (4 equiv.) in THF at 25 ꢁC for 24 h affor-
ded (2-iodocyclopropyl)methyl benzyl ether (2) in 32%
*
Corresponding author.
E-mail address: ktakai@cc.okayama-u.ac.jp (K. Takai).
0
022-328X/$ - see front matter ꢀ 2006 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2006.06.047

K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
521
yield along with the recovery of 1 in 64% yield (Eq. (1)).
The trans/cis ratio of the produced cyclopropanes was
3/37. Addition of several amines was examined, and the
Table 1
a
Iodocyclopropanation of alkenes
CHI , CrCl , TEEDA
3
2
6
R
R
I
yields and stereoselectivities of 2 with the amines (4 equiv.)
are as follows: Et N, 25% (trans/cis = 70/30); Me NCH -
THF, 25 ˚C
3
2
2
b
Entry
1
Alkene
Time (h)
4
Yield (%)
93
trans/cis
NMe , 0%; Me N(CH ) NMe (TMEDA), 87% (85/15);
2
2
2 2
2
n-C H
95/5
9
19
Me N(CH ) NMe , 69% (83/17); Et N(CH ) NEt
2
2
2 3
2
2
2 2
(
(
TEEDA), 97% (93/7); i-PrMeN(CH ) N(i-Pr)Me, 19%
2 2
0
2
3
4
16
89
97/3
71/29); DL-Me NCHPhCHPhNMe , 61% (82/18), 2,2 -
2
2
bipyridyl, 13% (64/36). It was found that both TMEDA
and TEEDA accelerate the iodocyclopropanation.
4
90 (3)
96 (4)
96/4
96/4
ð1Þ
8
8
The results of the iodocyclopropanation of alkenes with
iodoform, chromium(II) chloride, and TEEDA are shown
in Table 1. It is worth noting that the iodocyclopropanation
proceeded smoothly without the presence of a hydroxy or
an alkoxy group near the double bond (Table 1, entries 1–
Ph
5
6
4
8
97
97
93/7
97/3
BnO
4
), which is necessary for the cyclopropanation of iodoalk-
enes mediated with zinc carbenoids [1a]. On the other hand,
a steric hindrance around the double bond affected the yield
considerably. For example, terminal alkenes afforded the
corresponding iodocyclopropanes in 89–96% yields;
however, an (E)-disubstituted alkene [(E)-2-dodecene], a
Me SiO
9
3
c
7
8
8
8
87
95/5
91/9
1
,1-disubstituted alkene (2-methyl-1-undecene), and a tri-
HO
9
substituted alkene (2-methyl-2-dodecene) were recovered
unchanged after 24 h stirring at 25 ꢁC in 99%, 95% and
9
7% yields, respectively. The selectivity of the iodocyclo-
79
propanation is shown with a substrate having both a termi-
nal and trisubstituted (or 1,1-disubstituted) double bond; 3
and 4 were produced in selective manners, respectively
BnN
Me
(
entries 3 and 4). This reactivity contrasts with that of the
9
8
8
91
80
96/4
98/2
Simmons–Smith zinc carbenoid, which reacts faster with
more substituted electron-rich alkenes [10]. The iodocyclo-
propanation reaction proceeded without affecting the fol-
lowing functional groups: benzyl and silyl ethers, tertiary
amine, ester, and amide (entries 5, 6, 8–10). It is also worth
noting that the reaction proceeded without protecting the
hydroxyl group though 3 equiv. of the reagent was required
to obtain a high yield (entry 7). Electron-rich dodecyl vinyl
ether was recovered in 85% yield after being stirred for 24 h;
however, electron-deficient, a,b-unsaturated ester 5 reacted
with the reagent to give 6 in 37% yield (entry 11).
MeO C
9
2
1
1
0
O
Me2NC
9
1
24
37 (6)
78/22
O
Ph 3 O
5
The increased reactivity toward olefinic double bonds by
addition of TMEDA or TEEDA to the iodoform-chro-
mium(II) chloride reagent is further demonstrated using
terminal alkenes having carbonyl groups (Scheme 1). The
reagent derived from iodoform and chromium(II) chloride
in the absence of diamines reacted only with aldehyde and
ketone carbonyl groups, and selective iodoolefination
occurred to give iodoalkenes 7 and 8 in 83% and 74%
yields, respectively. An ester carbonyl group was inert to
the reagent, and 11 was recovered in 94% yield. In contrast,
a
The reactions were conducted on
a 1.0-mmol scale. Iodoform
(
1.5 mol), CrCl
alkene.
b
2
(4 mol), and TEEDA (4 mol) were used per mole of an
1
Isomeric ratios were determined by isolation and/or H NMR
spectroscopy.
c
Iodoform (3 mol), CrCl (8 mol), and TEEDA (8 mol) were used per
2
mole of 10-undecen-1-ol.
O
I
8
I
Ph
Ph
3O
I
3
4
6

522
K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
Silylcyclopropanation [11b]. Cyclopropylsilanes are use-
ful synthetic intermediates for organic synthesis [3]; how-
ever, their use has been quite limited due to the lack of
general preparative methods [4]. We examined using
Me SiCHI instead of iodoform, and found that the
3
2
reagent derived from Me SiCHI , chromium(II) chloride,
3
2
and TMEDA reacted with allyl benzyl ether to give the cor-
responding cyclopropylsilane. Treatment of allyl benzyl
ether (1) with the reagent generated in the presence of
TMEDA in THF at 25 ꢁC for 6 h gave [(2-benzyloxym-
ethyl)cyclopropyl]trimethylsilane (14) in 89% yield (trans/
cis = 69/31) (Table 2, entry 2). Addition of TEEDA was
most effective in the case of the iodocyclopropanation,
slightly improving the trans/cis ratio; however, the reaction
proceeded sluggishly (entry 3). The reduction rates of
Me SiCHX (X = halogen) with chromium(II) decreased
Scheme 1. Comparison of the reactivity in the presence and absence of
diamines.
3
2
when the halogen was changed from I to Br and Cl (entries
and 7). The problem was solved by adding LiI, which was
effective for substitution leading to Me SiCHI , and raising
4
when the diamines were added to the reaction mixture and
the amount of chromium(II) chloride reduced to half of the
iodoolefination reagent, the product distributions changed
markedly. Although the aldehyde 9 gave a complex mix-
ture, the terminal alkenes 10 and 11 were selectively con-
verted to the corresponding iodocyclopropanes 12 and 13
in 58% and 96% yields, respectively. The amount of chro-
mium(II) chloride was not important for this chemoselec-
tivity. For example, treatment of 10 with iodoform (2
equiv.) and chromium(II) chloride (4 equiv.) resulted in
iodoolefination but the yield of 8 decreased to 54% (E/
Z = 54/46), and 10 was recovered in 43% yield; 12 was
not detected. The dramatic effect on the reactivity of the
reagents derived from iodoform and chromium(II) chlo-
ride, caused by the addition of the diamines, suggests that
different reactive species are generated in the reaction
mixture.
3
2
the reaction temperature (entries 6 and 8). However, the
trans/cis ratio of 14 was still only about 2/1. Next, steric
hindrance caused by substitution on the silyl atom was
examined. Because only trimethyl-substituted diiodometh-
ylsilane (Me
[8d], reactions were conducted with a combination of
SiCHBr [12] and LiI instead of R SiCHI . The silylcy-
clopropanation of allyl benzyl ether proceeded similarly
at 50 ꢁC for 6 h with R SiCHBr in the presence of LiI to
SiCHI ) can be easily prepared in good yield
3
2
R
3
2
3
2
3
2
give the corresponding cyclopropylsilanes in excellent
yields (entries 9–11). The trans/cis ratio was improved by
using the bulky triisopropyl-substituted dibromomethylsi-
lane (entry 11).
The results obtained with several kinds of alkenes are
summarized in Table 3. Only terminal double bonds were
affected by the reaction; however, a trisubstituted olefin
Table 2
a
Formation of cyclopropylsilanes from allyl benzyl ether
R SiCHX , CrCl
3
2
2
BnO
SiR3
BnO
THF
1
b
Entry
R
3
Si
X
Additive
Temperature (ꢁC)
Time (h)
Yield (%)
16
trans/cis
1
2
3
4
5
6
7
8
9
Me Si (14)
3
I
I
I
None
25
25
25
25
25
50
50
85
50
50
50
24
6
24
24
24
6
24
12
6
50/50
69/31
73/27
64/36
60/40
67/33
–
64/36
67/33
71/29
87/13
c
TMEDA
89
TEEDA
25
49
74
Br
Br
Br
Cl
Cl
Br
Br
Br
TMEDA
d
TMEDA, LiI
TMEDA, LiI
TMEDA
TMEDA, LiI
TMEDA, LiI
TMEDA, LiI
TMEDA, LiI
89
0
87
92
96
82
PhMe
Et Si
i-Pr Si
2
Si
1
1
0
1
a
3
6
6
3
Reaction was conducted on a 1.0 mmol scale. Two mol of R
Eight mole of TMEDA (or TEEDA) and 4 mol of LiI were used per mole of allyl benzyl ether.
See Method A in Section 3.
3
SiCHX
2
2
, and 8 mol of CrCl were used per mole of allyl benzyl ether.
b
c
d
See Method B in Section 3.

K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
523
remained unchanged (Table 3, entry 3). In the case of the
conjugated diene, silylcyclopropanation occurred only at
the terminal olefin, and the stereochemistry of the internal
double bond did not change (entry 4).
ð2Þ
Although oxygen-functionalities near the carbon–car-
bon double bonds were not necessary to promote this silyl-
cyclopropanation (Table 3, entries 1–4), a hydroxyl group
accelerated the reaction markedly. For example, treatment
Borylcyclopropanation [5]. When Me SiCHI was
replaced by a combination of dichloromethylboronic ester
6 [13] and LiI, allyl benzyl ether was converted to the cor-
3
2
1
of 2-cyclohexen-1-ol with the reagent derived from Me Si-
3
responding boron-substituted cyclopropane 17 in 75%
yield although the stereoselectivity was low (Eq. (3)).
Because reduction of polyhalogen compounds with chro-
mium(II) increases in the order Cl < Br < I, addition of
LiI was indispensable to obtain the product in high yield.
A simple alkene having no oxygen functional group,
CHI , chromium(II) chloride, and TMEDA at 50 ꢁC for
2
1
2 h afforded cyclopropylsilane 15 in 65% yield as a single
stereoisomer (Eq. (2)) [6]. However, the reaction of cyclo-
hexene, a 1,2-disubstituted alkene, did not give the corre-
sponding cyclopropylsilane under the same reaction
conditions even in the presence of cyclohexanol as an
additive.
1-dodecene, was also converted to cyclopropylboronic ester
18 under the same reaction conditions.
Table 3
a
Preparation of cyclopropyltrimethylsilanes from terminal alkenes
Entry
1
Alkene
Time (h)
24
Product
Yield (%)
84
trans/cis
51/49
2
3
24
81
53/47
12
12
80
80
78/22
68/32
4
a
3 2 2
See Method A in Section 3. Reaction was conducted on a 1.0 mmol scale. Me SiCHI (2 mol), CrCl (8 mol), and TMEDA (8 mol) were used per mole
of an alkene.
Scheme 2. A plausible mechanism.

524
K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
ð4Þ
ð3Þ
We are tempted to assume that the chromium–alkylidene
species 21 could be involved in the cyclopropanation
(
Scheme 2). Reduction of RCHI with 4 equiv. of chro-
2
mium(II) gives geminal dichromium species 20. The dichro-
mium species 20 is converted to the chromium–alkylidene
complex 21 by treatment with the diamine [17]. A [2+2]
addition reaction of 21 with an alkene followed by reductive
elimination from the chromacyclobutane 22 produces the
heterosubstitutedcyclopropane [19]. The comproportiona-
Proposed reaction mechanism of the heterosubstituted
cyclopropanation. Cyclopropanation of alkenes can be
accomplished by both metal-carbenoid species and metal–
carbene complexes [14]. Thus, there are two possible reac-
tion pathways for the production of iodocyclopropanes
tion of both 1 equiv. of CrX and CrX generating 2 equiv.
3
of CrX could reduce the amount of the required CrCl .
2
2
(
Scheme 2). The active species of path A is the chro-
mium–carbenoid 19, and that of path B is the chro-
mium–carbene species 21 [15].
3. Experimental
One important feature of the reduction of polyhalogen
compounds with chromium(II) is that the reduction step
from the chromium carbenoid species 19 to geminal dichro-
mium species 20 proceeds smoothly [8,16]. Reduction of
iodoform, R SiCHI , and (RO) BCHI with 4 equiv. of
chromium(II) gives the corresponding geminal dichromium
species, which are effective for transformation from alde-
hydes to iodoolefins [8a], alkenylsilanes [8b], and -boronic
esters [8c], of E-configuration, respectively. Once chro-
mium carbenoid 19 was reduced with chromium(II) to gen-
erate the geminal dichromium species 20, it could be
difficult to regenerate the chromium carbenoid 19 under
the reduction conditions. Therefore, we examined the fol-
lowing reactions. The geminal dichromium reagent was
generated by stirring iodoform (1.5 equiv.) and chro-
mium(II) chloride (4 equiv.) in THF at 25 ꢁC for 30 min.
Formation of the reagent was examined by treatment with
Experimental conditions. Dry, oxygen-free tetrahydrofu-
ran (THF) was purchased from Kanto Chemicals, Co. Col-
umn chromatography was performed with silica gel (200
mesh). Analytical samples of isomers were collected by
recycling preparative HPLC (Japan Analytical Industry,
LC-908) using toluene as an eluent. Distillation of small
amounts of the products was performed with a Buchi
Kugelrohr, and boiling points were indicated by an air bath
temperature without correction. FT-IR spectra were
3
2
2
2
1
obtained on a Nicolet Protege 460 spectrometer. H and
1
3
C NMR spectra were recorded on a JEOL JNM-LA400
instrument. Chemical shifts were expressed in ppm down-
field from internal tetramethylsilane using a scale. Low
and high resolution EI mass spectra were obtained with a
capillary GC interfaced JEOL JMS-GCmate and JMS-
700 MStation spectrometers, respectively. Elemental analy-
ses were performed by the staff at the Elemental Analyses
Center of Kyoto University.
3
7
-phenylpropanal, which gave 1-iodo-4-phenyl-1-butene in
0% yield (E/Z = 82/18) after stirring at 25 ꢁC for 30 min
[
8a]. In contrast, when TMEDA (4 equiv.) was added to
General procedure for iodocyclopropanation of terminal
alkenes. To a mixture of CrCl (0.49 g, 4.0 mmol) in dry,
the geminal dichromium reagent generated at 25 ꢁC for
h, and the mixture was stirred for a further 15 min, treat-
ment of 10 with the new base-added reagent at 25 ꢁC for
h gave 12 in 38% yield (trans/cis = 80/20) along with 8
2
1
oxygen-free THF (5 mL) was added TEEDA (0.85 mL,
4.0 mmol) at 25 ꢁC. The color of the mixture turned from
greenish white to purple. After stirring for 15 min at
25 ꢁC, a solution of an alkene (1.0 mmol) in THF (2 mL)
was added to the mixture at 25 ꢁC. A solution of iodoform
(0.59 g, 1.5 mmol) in THF (3 mL) was added dropwise to
the mixture at 25 ꢁC over a period of 5 min. The color of
the mixture turned to brown and then black. After stirring
for an appropriate time shown in Table 1 at 25 ꢁC, the
reaction mixture was poured into aqueous hydrochloric
acid (1 M, 15 mL). The mixture was extracted with ether
(3 · 20 mL), and organic extracts were washed with aque-
ous sodium thiosulfate (2 · 20 mL), dried over anhydrous
magnesium sulfate and concentrated. Purification by col-
umn chromatography on silica gel gave the desired
iodocyclopropane.
2
in 1% yield; the reactant 10 was recovered in 37% yield.
The results suggest that the cyclopropanation does not pro-
ceed via the carbenoid pathway (path B).
It has been reported that the dimetallic species 23 of
early transition metals are postulated in equilibrium with
the metal–alkylidene complex 24 and MXn+1 (Eq. (4))
[
17], and the equilibrium-shift is caused especially by the
addition of an appropriate amine [4]. For example, the
equilibrium-shift from the Tebbe reagent to a titanocene–
methylene complex occurs by addition of pyridine, and
the complex reacts with 2-methylpropene [18]. As men-
tioned earlier (Scheme 1), the reactivity of the species
derived from iodoform and chromium(II) chloride changes
markedly by addition of TMEDA or TEEDA, and that
trans-iodocyclopropanes are produced stereoselectively
from terminal alkenes by treatment with the base-added
reagent system.
trans-(2-Iodocyclopropyl)methyl benzyl ether (2) [7a].
IR (neat): 3029, 2856, 1496, 1453, 1253, 1212, 1095, 1077,
ꢀ
1 1
1039, 737 cm ; H NMR (CDCl ): d 0.98-1.02 (m, 2H),
3
1.49–1.57 (m, 1H), 2.23–2.27 (m, 1H), 3.35 (dd, J = 10.5,

K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
525
6
.6 Hz, 1H), 3.44 (dd, J = 10.5, 6.3 Hz, 1H), 4.51 (d,
0.89 (ddd, J = 9.0, 6.0, 4.2 Hz, 1H), 1.11–1.18 (m, 1H),
1.19–1.39 (m, 15H), 1.57 (tt, J = 6.9, 6.9 Hz, 2H), 2.07
(ddd, J = 7.7, 3.9, 3.9 Hz, 1H), 3.64 (q, J = 6.1 Hz, 2H);
J = 12.0 Hz, 1H), 4.54 (d, J = 12.0 Hz, 1H), 7.26–7.38
1
3
(
7
m, 5H); C NMR (CDCl ): d ꢀ17.6, 14.6, 22.9, 71.6,
3
1
3
2.6, 127.7, 127.7, 128.4, 138.0.
trans-1-Iodo-2-nonylcyclopropane. B.p. 110 ꢁC (bath
C NMR (CDCl ): d ꢀ14.7, 16.5, 23.7, 25.7, 28.7, 29.3,
3
29.3, 29.4, 29.5, 32.8, 33.5, 63.0. Silylation of the alcohol
afforded the above compound.
temperature, 0.9 Torr); IR (neat): 2955, 2924, 2853, 1465,
1
ꢀ
1
1
441, 1378, 1216, 1194, 1076, 1034 cm
;
H NMR
trans-Benzyl(2-iodocyclopropylmethyl)methylamine. IR
(neat): 2788, 1453, 1365, 1216, 1193, 1075, 1039, 1025,
(
CDCl ): d 0.78 (ddd, J = 7.8, 4.0, 4.0 Hz, 1H), 0.87–0.91
3
ꢀ
1 1
(
m, 4H), 1.11–1.19 (m, 1H), 1.24–1.32 (m, 14H), 1.35–
739, 699 cm ; H NMR (CDCl ): d 0.79 (ddd, J = 7.7,
3
1
3
1
.42 (m, 2H), 2.07 (ddd, J = 7.8, 4.0, 4.0 Hz, 1H);
C
6.2, 6.2 Hz, 1H), 0.93 (ddd, J = 9.3, 6.3, 4.5 Hz, 1H),
1.31–1.36 (m, 1H), 2.04–2.13 (m, 2H), 2.24 (s, 3H), 2.48
(dd, J = 12.9, 5.7 Hz, 1H), 3.45 (d, J = 12.9 Hz, 1H), 3.67
NMR (CDCl ): d ꢀ14.6, 14.1, 16.6, 22.7, 23.7, 28.7, 29.3,
3
2
9.4, 29.6, 29.6, 31.9, 33.5. Anal. Calc. for C H I: C,
12 23
1
3
4
8.99; H, 7.88. Found: C, 49.27; H, 7.75%.
trans-(2-Iodocyclopropyl)cyclohexane. B.p. 57 ꢁC (bath
temperature, 0.6 Torr); IR (neat): 2922, 2851, 1448, 1241,
(d, J = 13.2 Hz, 1H), 7.19–7.29 (m, 5H);
C NMR
(CDCl ): d ꢀ15.1, 15.3, 21.5, 42.4, 60.6, 62.1, 127.0,
3
128.3, 129.0,138.9. Anal. Calc. for C H IN: C, 47.86;
1
2
16
ꢀ
1 1
1
0
1
2
208, 1192, 1063, 1035, 936 cm ; H NMR (CDCl ): d
H, 5.35. Found: C, 47.88; H, 5.23%.
Methyl trans-10-(2-iodocyclopropyl)decanoate.
(neat): 2926, 2854, 1740, 1436, 1361, 1196, 1172,
3
.58–0.68 (m, 1H), 0.79–0.88 (m, 2H), 0.98–1.08 (m, 2H),
.12–1.20 (m, 4H), 1.60–1.74 (m, 4H), 1.78–1.85 (m, 1H),
IR
1
3
ꢀ1
1
.13 (ddd, J = 7.3, 4.2, 4.2 Hz, 1H); C NMR (CDCl3):
1034 cm ; H NMR (CDCl ): d 0.78 (ddd, J = 7.5, 6.0,
3
d ꢀ16.4, 15.3, 26.0, 26.0, 26.3, 30.0, 32.0, 32.2, 42.2. Anal.
6.0 Hz, 1H), 0.89 (ddd, J = 9.0, 6.0, 4.2 Hz, 1H), 1.10–
1.19 (m, 1H), 1.26–1.33 (m, 12H), 1.35–1.43 (m, 2H),
1.56–1.67 (m, 2H), 2.07 (ddd, J = 7.8, 3.9, 3.9 Hz, 1H),
Calc. for C H I: C, 43.22; H, 6.04. Found: C, 43.35; H,
9
15
5
.90%.
1
3
trans-1-Iodo-2-(10-methyl-9-undecenyl)cyclopropane
3). IR (neat): 2993, 2965, 2853, 1455, 1441, 1376, 1217,
2.30 (t, J = 7.5 Hz, 2H), 3.67 (s, 3H); C NMR (CDCl3):
d ꢀ14.7, 16.5, 23.7, 24.9, 26.9, 28.6, 29.1, 29.1, 29.2, 29.3,
33.5, 34.1, 51.4, 174.3. Anal. Calc. for C H IO : C,
(
1
6
1
2
ꢀ
1 1
192, 1034 cm ; H NMR (CDCl ): d 0.78 (ddd, J = 7.6,
3
14 25
2
.2, 6.1 Hz, 1H), 0.89 (ddd, J = 9.0, 6.0, 4.5 Hz, 1H),
.08–1.19 (m, 1H), 1.24–1.32 (m, 12H), 1.33–1.41 (m,
H), 1.60 (s, 3H), 1.69 (s, 3H), 1.92–2.00 (m, 2H), 2.07
47.74; H, 7.15. Found: C, 47.97; H, 6.98%.
N,N-Dimethyl [trans-10-(2-iodocyclopropyl)]decana-
mide. IR (neat): 3542, 2924, 2853, 1649, 1463, 1397,
ꢀ
1 1
(
ddd, J = 7.8, 3.9, 3.9 Hz, 1H), 5.11 (t, J = 7.3 Hz, 1H);
1265, 1145, 1034 cm ; H NMR (CDCl ): d 0.78 (ddd,
3
1
3
C NMR (CDCl ): d ꢀ14.7, 16.5, 17.7, 23.7, 25.7, 28.0,
J = 7.5, 6.0, 6.0 Hz, 1H), 0.88 (ddd, J = 9.0, 6.0,
4.4 Hz, 1H), 1.10–1.19 (m, 1H), 1.23–1.42 (m, 14H),
1.59–1.66 (m, 2H), 2.07 (ddd, J = 7.8, 3.9, 3.9 Hz, 1H),
3
2
8.7, 29.3, 29.3, 29.5, 29.5, 29.9, 33.5, 124.9, 131.1. Anal.
Calc. for C H I: C, 53.90; H, 8.14. Found: C, 53.98; H,
1
5
27
1
3
7
.93%.
2.30 (t, J = 7.6 Hz, 2H), 2.94 (s, 3H), 3.00 (s, 3H);
C
trans-[3-(2-Iodocyclopropylmethyl)-3-butenyl]benzene
4). IR (neat): 3026, 2924, 2857, 1645, 1496, 1453, 1437,
NMR (CDCl ): d ꢀ14.7, 16.5, 23.7, 25.1, 26.9, 28.7,
3
(
1
29.3, 29.3, 29.4, 29.4, 33.4, 33.5, 35.3, 37.3, 173.2. Anal.
ꢀ
1 1
214, 1189, 1035, 894, 747, 698 cm ; H NMR (CDCl ):
Calc. for C H INO: C, 49.32; H, 7.73. Found: C,
3
15 28
d 0.84 (ddd, J = 7.8, 6.1, 6.1 Hz, 1H), 0.96 (ddd, J = 9.1,
49.08; H, 7.48%.
3-Phenylpropyl
4
7
2
1
.6, 3.1 Hz, 1H), 1.24–1.34 (m, 1H), 1.96 (dd, J = 15.9,
.5 Hz, 1H), 2.04–2.12 (m, 2H), 2.34 (dd, J = 8.4, 7.6 Hz,
H), 2.74 (dd, J = 8.4, 7.6 Hz, 2H), 4.82 (s, 1H), 4.89 (s,
trans-2-iodocyclopropanecarboxylate
(trans-6). IR (neat): 3026, 2954, 1726, 1398, 1367, 1229,
ꢀ
1 1
1195, 1026 cm ; H NMR (CDCl ): d 1.30 (ddd, J = 8.8,
3
1
3
H), 7.15–7.29 (m, 5H); C NMR (CDCl ): d ꢀ14.7,
5.8, 5.8 Hz, 1H), 1.62 (ddd, J = 8.2, 5.6, 5.6 Hz, 1H),
1.94–2.02 (m, 3H), 2.70 (t, J = 7.6 Hz, 2H), 2.75 (ddd,
J = 8.3, 5.5, 3.6 Hz, 1H), 4.11 (t, J = 6.6 Hz, 2H), 7.18–
3
1
1
6.6, 22.0, 26.9, 34.4, 38.0, 40.2, 110.4, 125.8, 128.3,
42.0, 147.4. Anal. Calc. for C H I: C, 53.86; H, 5.49.
1
4
17
1
3
Found: C, 53.98; H, 5.51%.
7.40 (m, 5H); C NMR (CDCl ): d ꢀ17.1, 19.7, 24.6,
3
trans-[9-(2-Iodocyclopropyl)nonyloxy]trimethylsilane.
30.1, 32.1, 64.6, 126.1, 128.4, 128.5, 141.0, 172.0. Anal.
Calc. for C H IO : C, 47.29; H, 4.58. Found: C, 47.55;
ꢀ
1
IR (neat): 2926, 2854, 1259, 1250, 1097, 873, 841, 747 cm
;
1
3
15
2
1
H NMR (CDCl ): d 0.11 (s, 9H), 0.78 (ddd, J = 7.5, 6.0,
H, 4.57%.
3
6
.0 Hz, 1H), 0.89 (ddd, J = 9.0, 6.0, 4.5 Hz, 1H), 1.10–
.18 (m, 1H), 1.25–1.35 (m, 12H), 1.35–1.42 (m, 2H),
.48–1.56 (m, 2H), 2.07 (ddd, J = 7.7, 4.2, 3.8 Hz, 1H),
3-Phenylpropyl cis-2-iodocyclopropanecarboxylate (cis-
6). IR (neat): 3026, 2954, 2926, 1732, 1399, 1371, 1249,
1
1
3
ꢀ1
1
1172 cm
;
H NMR (CDCl ): d 1.39–1.44 (m, 1H),
3
1
3
.57 (t, J = 6.8 Hz, 2H); C NMR (CDCl ): d ꢀ14.7,
1.49–1.54 (m, 1H), 1.89 (ddd, J = 8.7, 7.4, 7.2 Hz, 1H),
1.97–2.06 (m, 2H), 2.73 (t, J = 7.8 Hz, 2H), 2.82 (ddd,
J = 8.8, 7.3, 7.3 Hz, 1H), 4.15–4.27 (m, 2H), 7.18–7.31
3
ꢀ
0.5, 16.5, 23.7, 25.8, 28.7, 29.3, 29.4, 29.5, 29.5, 32.7,
3
3.5, 62.7. Anal. Calc. for C H IOSi: C, 47.11; H, 8.17.
1
5
31
1
3
Found: C, 47.29; H, 8.31%.
(m, 5H); C NMR (CDCl ): d ꢀ14.6, 16.4, 19.3, 30.4,
3
trans-9-(2-Iodocyclopropyl)nonan-1-ol. IR (neat): 3338,
32.2, 64.6, 126.0, 128.4, 128.4, 141.2, 169.9. Anal. Calc.
for C H IO : C, 47.29; H, 4.58. Found: C, 47.51; H,
ꢀ
1 1
2
924, 2853, 1464, 1439, 1218, 1192, 1057, 1034 cm ; H
1
3
15
2
NMR (CDCl ): d 0.78 (ddd, J = 7.5, 6.0, 6.0 Hz, 1H),
4.56%.
3

526
K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
trans-10-(2-Iodocyclopropyl)-2-decanone (trans-12). IR
neat): 2925, 2853, 1717, 1437, 1358, 1192, 1163 cm ; H
[cis-2-(Benzyloxymethyl)cyclopropyl]trimethylsilane
(cis-14). IR (neat): 2953, 2855, 1454, 1247, 1090, 1029,
ꢀ1 1
(
ꢀ
1 1
836, 751, 735, 697, 648 cm ; H NMR (CDCl ): d ꢀ0.25
NMR (CDCl ): d 0.78 (ddd, J = 7.0, 6.9, 6.0 Hz, 1H),
3
3
0
1
2
2
1
4
.88 (ddd, J = 9.0, 6.0, 4.2 Hz, 1H), 1.10–1.18 (m, 1H),
.25–1.31 (m, 10H), 1.34–1.39 (m, 2H), 1.54–1.60 (m,
H), 2.07 (ddd, J = 7.8, 3.9, 3.9 Hz, 1H), 2.13 (s, 3H),
(ddd, J = 9.5, 9.5, 7.8 Hz, 1H), ꢀ0.01 (s, 9H), 0.20–0.24
(m, 1H), 0.84–0.89 (m, 1H), 1.33–1.43 (m, 1H), 3.32 (dd,
J = 9.7, 7.8 Hz, 1H), 3.41 (dd, J = 9.7, 7.1 Hz, 1H), 4.52
1
3
13
.41 (t, J = 7.4 Hz, 2H); C NMR (CDCl ): d ꢀ14.7,
(s, 2H), 7.26–7.35 (m, 5H); C NMR (CDCl ): d ꢀ0.3,
3
3
6.5, 23.7, 23.8, 28.7, 29.1, 29.2, 29.3, 29.3, 29.9, 33.5,
3.8, 209.4. Anal. Calc. for C H IO: C, 48.46; H, 7.19.
2.1, 7.8, 16.3, 72.7, 72.9, 127.5, 127.9, 128.3, 138.4. Anal.
Calc. for C H Si: C, 71.73; H, 9.46. Found: C, 71.84;
1
3
23
14 22
Found: C, 48.74; H, 7.36%.
H, 9.68%.
cis-10-(2-Iodocyclopropyl)-2-decanone (cis-12). IR
neat): 2924, 2852, 1717, 1457, 1437, 1361, 1056 cm ; H
[trans-2-(Benzyloxymethyl)cyclopropyl]dimethylphenylsi-
lane. IR (neat): 2954, 2852, 1427, 1248, 1113, 1098, 832,
ꢀ1 1
(
ꢀ1 1
NMR (CDCl ): d 0.42–0.52 (m, 2H), 0.81–0.90 (m, 1H),
814, 773, 732, 699, 667 cm ; H NMR (CDCl ): d ꢀ0.26
3
3
1
2
1
2
.24–1.36 (m, 10H), 1.41–1.52 (m, 2H), 1.53–1.61 (m,
(ddd, J = 9.8, 6.6, 6.6 Hz, 1H), 0.20 (s, 3H), 0.21 (s, 3H),
0.54–0.57 (m, 2H), 1.06–1.14 (m, 1H), 3.31 (dd, J = 10.0,
7.1 Hz, 1H), 3.48 (dd, J = 10.0, 6.4 Hz, 1H), 4.52 (s, 2H),
H), 2.13 (s, 3H), 2.42 (t, J = 7.5 Hz, 2H), 2.58–2.65 (m,
1
3
H); C NMR (CDCl ): d ꢀ6.1, 15.6, 15.8, 23.8, 28.5,
3
1
3
9.1, 29.3, 29.3, 29.4, 29.8, 35.0, 43.8, 209.4. Anal. Calc.
7.27–7.59 (m, 10H); C NMR (CDCl ): d ꢀ3.9, ꢀ3.8,
3
for C H IO: C, 48.46; H, 7.19. Found: C, 48.56; H,
1.3, 7.6, 15.1, 72.4, 75.7, 127.4, 127.6, 127.7, 128.3, 128.9,
133.8, 138.6, 138.9. Anal. Calc. for C H OSi: C, 76.97;
1
3
23
7
.37%.
1
9
24
trans-9-(2-Iodocyclopropyl)nonyl acetate (13). IR
H, 8.16. Found: C, 77.27; H, 8.16%.
[cis-2-(Benzyloxymethyl)cyclopropyl]dimethylphenylsi-
lane. IR(neat): 2954, 2855, 1427, 1248, 1112, 1091, 833,
ꢀ1
1
(
neat): 2925, 2854, 1741, 1365, 1240, 1036 cm
NMR (CDCl ): d 0.77 (ddd, J = 12.0, 7.5, 6.0 Hz, 1H),
;
H
3
ꢀ
1 1
0
1
2
(
2
.89 (ddd, J = 9.1, 5.9, 4.4 Hz, 1H), 1.09–1.17 (m, 1H),
815, 773, 733, 699, 666 cm ; H NMR (CDCl ): d ꢀ0.02
3
.21–1.41 (m, 14H), 1.56–1.66 (m, 2H), 2.04 (s, 3H),
(ddd, J = 9.5, 9.5, 7.8 Hz, 1H), 0.25 (s, 3H), 0.28 (s, 3H),
0.30–0.34 (m, 1H), 0.94–0.99 (m, 1H), 1.41–1.49 (m, 1H),
3.28 (d, J = 7.3 Hz, 2H), 4.44 (s, 2H), 7.28–7.59 (m,
1
3
.05–2.08 (m, 1H), 4.04 (t, J = 6.8 Hz, 2H); C NMR
CDCl ): d ꢀ14.7, 16.5, 21.0, 23.7, 25.9, 28.6, 28.7, 29.2,
3
1
3
9.3, 29.4, 29.4, 33.5, 64.6, 171.2. Anal. Calc. for
10H); C NMR (CDCl ): d ꢀ1.6, 1.4, 8.0, 16.5, 72.6,
3
C H IO : C, 47.74; H, 7.15. Found: C, 48.03; H, 6.93%.
76.5, 127.5, 127.7, 127.8, 128.3, 128.8, 133.7, 138.3, 139.8.
Anal. Calc. for C H OSi: C, 76.97; H, 8.16. Found: C,
1
4
25
2
General procedure for silylcyclopropanation of terminal
alkenes (Method A). To a greenish gray suspension of CrCl2
0.98 g, 8.0 mmol) in dry, oxygen-free THF (12 mL) was
1
9
24
76.87, H, 8.30%.
(
[trans-2-(Benzyloxymethyl)cyclopropyl]triethylsilane.
added TMEDA (0.93 g, 8.0 mmol) at 25 ꢁC and the result-
ing light blue mixture was stirred at 25 ꢁC for 15 min. A
solution of an alkene (1.0 mmol) in THF (2 mL) and a solu-
tion of Me SiCHI (0.68 g, 2.0 mmol) in THF (3 mL) was
IR (neat): 2953, 2874, 1720, 1455, 1098, 1016, 736, 697,
ꢀ1
1
666 cm
;
H NMR (CDCl ): d ꢀ0.54 (ddd, J = 10.2,
3
6.8, 6.8 Hz, 1H), 0.44–0.54 (m, 2H), 0.47 (q,
J = 7.9 Hz, 6H), 0.94 (t, J = 7.9 Hz, 9H), 1.03–1.12
(m, 1H), 3.19 (dd, J = 10.3, 7.6 Hz, 1H), 3.52 (dd,
J = 10.3, 5.9 Hz, 1H), 4.54 (s, 2H), 7.26–7.34 (m, 5H);
3
2
added successively to the suspension at 25 ꢁC. The mixture
was stirred at 25 ꢁC for an appropriate time shown in Table
1
3
3
, and the color changed gradually to dark brown while
C NMR (CDCl ): d ꢀ1.4, 2.9, 7.4, 7.5, 14.5, 72.4,
3
stirring. The mixture was poured into water (10 mL). This
mixture was extracted with ether (3 · 10 mL), and the
organic extracts were dried over anhydrous magnesium
sulfate and concentrated. Purification by column chroma-
tography on silica gel (hexane) gave the desired silylcyclo-
propanes. Analytical samples of trans- and cis-isomers
were collected by recycling preparative HPLC.
76.1, 127.4, 127.6, 128.3, 138.7. Anal. Calc. for
C H OSi: C, 73.85; H, 10.21. Found: C, 73.57; H,
1
7
28
10.22%.
[cis-2-(Benzyloxymethyl)cyclopropyl]triethylsilane. IR
ꢀ
1
1
(neat): 2952, 2873, 1455, 1091, 734, 697, 667 cm ; H
NMR (CDCl ): d ꢀ0.28 (ddd, J = 9.8, 9.8, 8.1 Hz, 1H),
3
0.21–0.26 (m, 1H), 0.42–0.54 (m, 6H), 0.86–0.96 (m,
10H), 1.33–1.39 (m, 1H), 3.19 (dd, J = 10.0, 8.5 Hz, 1H),
3.52 (dd, J = 10.0, 6.1 Hz, 1H), 4.52 (s, 2H), 7.26–7.35
Method B. A combination of i-Pr SiCHBr2 (0.66 g,
3
2
.0 mmol) and LiI (0.53 g, 4.0 mmol) was used instead of
1
3
Me SiCHI in Method A.
(m, 5H); C NMR (CDCl ): ꢀ1.6, 4.4, 7.5, 7.9, 15.6,
3
2
3
[
trans-2-(Benzyloxymethyl)cyclopropyl]trimethylsilane
72.6, 73.3, 127.5, 127.8, 128.3, 138.4. Anal. Calc. for
C H OSi: C, 73.85; H, 10.21. Found: C, 73.57; H,
(
8
trans-14). IR (neat): 2954, 2853, 1454, 1248, 1096, 1028,
1
7
28
ꢀ1 1
36, 747, 735, 697, 666 cm ; H NMR (CDCl ): d ꢀ0.50
10.45%.
[trans-2-(Benzyloxymethyl)cyclopropyl]triisopropylsi-
lane. IR (neat): 2942, 2865, 1464, 1098, 1075, 882, 734, 696,
3
(
(
ddd, J = 13.7, 7.1, 7.1 Hz, 1H), ꢀ0.04 (s, 9H), 0.44–0.51
m, 2H), 0.98–1.03 (m, 1H), 3.24 (dd, J = 10.1, 7.1 Hz,
ꢀ
1 1
1
7
7
H), 3.47 (dd, J = 10.1, 5.9 Hz, 1H), 4.54 (s, 2H), 7.26–
666 cm ; H NMR (CDCl ): d ꢀ0.56 (ddd, J = 6.8, 6.8,
3
1
3
.35 (m, 5H); C NMR (CDCl ): d ꢀ2.4, 2.3, 7.5, 14.9,
10.0 Hz, 1H), 0.49–0.53 (m, 1H), 0.64–0.69 (m, 1H),
1.01–1.05 (m, 21H), 1.17–1.25 (m, 1H), 3.12 (dd, J = 9.8,
10.0 Hz, 1H), 3.59 (dd, J = 5.5, 10.0 Hz, 1H), 4.55 (s,
3
2.3, 75.9, 127.4, 127.6, 128.3, 138.6. Anal. Calc. for
C H Si: C, 71.73; H, 9.46. Found: C, 71.55; H, 9.46%.
1
4
22

K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
527
1
3
2
1
1
H), 7.27–7.52 (m, 5H); C NMR (CDCl ): d ꢀ2.9, 8.5,
[trans-2-(5-Methyl-1-methylene-4-hexenyl)cyclopropyl]-
trimethylsilane. IR (neat): 2955, 2927, 1642, 1448, 1248,
3
2.1, 15.6, 19.0, 19.0, 72.7, 73.4, 127.5, 127.9, 128.3,
38.4. Anal. Calc. for C H OSi: C, 75.40; H, 10.76.
Found: C, 75.28; H, 10.77%.
cis-2-(Benzyloxymethyl)cyclopropyl]triisopropylsilane.
IR (neat): 2942, 2865, 1464, 1077, 883, 731, 697, 677 cm
ꢀ
1
1
835, 751, 690, 667 cm
;
H NMR (CDCl ): d ꢀ0.25
2
0
34
3
(ddd, J = 10.3, 7.5, 7.5 Hz, 1H), ꢀ0.04 (s, 9H), 0.53 (ddd,
J = 7.5, 7.5, 3.7 Hz, 1H), 0.72 (ddd, J = 10.3, 4.9, 3.7 Hz,
1H), 1.18–1.23 (m, 1H), 1.62 (s, 3H), 1.69 (s, 3H), 2.01 (t,
J = 7.7 Hz, 2H), 2.12–2.18 (m, 2H), 4.62 (s, 1H), 4,66 (s,
[
ꢀ
1
;
1
H NMR (CDCl ): d ꢀ0.28 (ddd, J = 9.0, 9.5, 9.5 Hz 1H),
3
1
3
0
3
1
.37–0.41 (m, 1H), 0.90–1.04 (m, 22H), 1.34–1.43 (m, 1H),
1H), 5.12 (t, J = 6.8 Hz, 1H); C NMR (CDCl ): d ꢀ2.4,
3
.08 (dd, J = 9.5, 9.5 Hz, 1H), 3.70 (dd, J = 5.3, 9.8 Hz,
H), 4.54 (q, J = 11.9 Hz, 2H), 7.27–7.38 (m, 5H);
6.4, 9.6, 17.7, 20.5, 25.7, 27.0, 35.6, 105.8, 124.2, 131.5,
151.5. Anal. Calc. for C H Si: C, 75.59; H, 11.78. Found:
1
3
C
1
4
26
NMR (CDCl ): d ꢀ2.9, 8.2, 11.2, 14.9, 18.8, 72.6, 76.4,
C, 75.32; H, 11.81%.
[cis-2-(5-Methyl-1-methylene-4-hexenyl)cyclopropyl]tri-
3
1
27.4, 127.6, 128.3, 138.6. Anal. Calc. for C H OSi: C,
2
0
34
7
5.40; H, 10.76. Found: C, 75.31; H, 10.80%.
Trimethyl[trans-2-(2-phenethyl-2-propenyl)cyclopropyl]-
silane. IR (neat): 2953, 1645, 1497, 1454, 1247, 1048, 1032,
methylsilane. IR (neat): 2954, 2927, 1643, 1450, 1249, 835,
ꢀ
1
1
753, 689, 666 cm
;
H NMR (CDCl ): d ꢀ0.15 (ddd,
3
J = 10.0, 10.0, 7.6 Hz, 1H), ꢀ0.03 (s, 9H), ꢀ0.07–0.00
(m, 1H), 0.66 (ddd, J = 7.6, 5.6, 3.8 Hz, 1H), 0.83 (ddd,
J = 11.2, 7.5, 3.7 Hz, 1H), 1.62 (s, 3H), 1.69 (s, 3H),
2.11–2.27 (m, 4H), 4.68 (s, 1H), 4,74 (s, 1H), 5.14–5.17
ꢀ1 1
8
82, 747, 698, 666 cm ; H NMR (CDCl ): d ꢀ0.60 (ddd,
3
J = 9.8, 6.8, 6.8 Hz, 1H), ꢀ0.07 (s, 9H), 0.34 (ddd, J =
1
1
2
2
7
3
0.5, 3.6, 3.6 Hz, 1H), 0.42 (ddd, J = 7.1, 7.1, 3.6 Hz,
H), 0.69–0.76 (m, 1H), 1.91 (dd, J = 15.5, 7.1 Hz, 1H),
.10 (dd, J = 15.5, 6.4 Hz, 1H), 2.36 (t, J = 8.4 Hz, 2H),
.75 (t, J = 8.4 Hz, 2H), 4,77 (s, 1H), 4,87 (s, 1H), 7.10–
1
3
(m, 1H); C NMR (CDCl ): d ꢀ0.5, 6.0, 6.6, 17.7, 22.0,
3
25.7, 26.5, 37.8, 108.8, 124.2, 131.6, 148.8; EI MS m/z
+
(%): 222 (M , 1), 207 (1), 179 (10), 73 (100), 69 (20).
1
3
+
.30 (m, 5H); C NMR (CDCl ): d ꢀ2.3, 4.5, 8.9, 14.2,
HRMS (EI) m/z calcd. for (M ) C H Si 222.1804, found
3
14 26
4.4, 38.1, 42.6, 109.0, 125.8, 128.3, 128.3, 142.3, 149.6.
222.1811.
Anal. Calc. for C H Si: C, 79.00; H, 10.14. Found: C,
[trans-2-(10-Methyl-9-undecenyl)cyclopropyl]trimeth-
ylsilane. IR (neat): 2924, 2854, 1456, 1247, 1031, 835, 728,
1
7
26
7
8.70; H, 10.20%.
Trimethyl[cis-2-(2-phenethyl-2-propenyl)cyclopropyl]-
silane. IR (neat): 2952, 1646, 1497, 1455, 1247, 1031, 833,
ꢀ1 1
694, 666 cm ; H NMR(CDCl ): d ꢀ0.72 (ddd, J = 9.8,
3
6.6, 6.6 Hz, 1H), ꢀ0.08 (s, 9H), 0.24–0.28 (m, 1H), 0.31–
0.35 (m, 1H), 0.52–0.60 (m, 1H), 1.03–1.09 (m, 1H),
1.26–1.42 (m, 13H), 1.60 (s, 3H), 1.69 (s, 3H), 1.93–1.98
ꢀ
1
1
7
48, 697, 666 cm
J = 10.2, 10.2, 7.2 Hz, 1H), 0.02 (s, 9H), 0.09–0.13 (m,
H), 0.80–0.86 (m, 1H), 1.09–1.15 (m, 1H), 1.79 (dd,
J = 15.6, 8.8 Hz, 1H), 2.27 (dd, J = 15.6, 5.1 Hz, 1H),
;
H NMR (CDCl ): d ꢀ0.32 (ddd,
3
1
3
1
(m, 2H), 5.11 (t, J = 7.1 Hz, 1H); C NMR (CDCl ): d
3
ꢀ2.3, 1.0, 4.3, 8.8, 15.6, 17.6, 25.7, 28.0, 29.4, 29.5, 29.6,
2
1
.37 (t, J = 8.6 Hz, 2H), 2.76 (t, J = 8.6 Hz, 2H), 4,81 (s,
H), 4,93 (s, 1H), 7.18–7.30 (m, 5H); C NMR (CDCl3):
29.7, 29.9, 36.0, 124.9, 131.1. Anal. Calc. for C H Si:
1
8
36
1
3
C, 77.06; H, 12.93. Found: C, 77.01; H, 13.23%.
[cis-2-(10-Methyl-9-undecenyl)cyclopropyl]trimethylsi-
lane. IR (neat): 2925, 2854, 1457, 1247, 834, 728, 694,
d ꢀ0.1, 2.6, 9.1, 15.3, 34.4, 38.2, 38.3, 38.6, 109.2, 125.8,
1
28.3, 142.3, 149.6. Anal. Calc. for C H Si: C, 79.00;
1
7
26
ꢀ
1 1
H, 10.14. Found: C, 79.12; H, 10.18%.
667 cm ; H NMR(CDCl ): d ꢀ0.44 (ddd, J = 9.8, 9.8,
3
[
trans-2-(Cyclohexylidenemethyl)cyclopropyl]trimeth-
7.3 Hz, 1H), 0.03 (s, 9H), 0.69–0.74 (m, 1H), 0.89–0.95
(m, 1H), 1.00–1.07 (m, 1H), 1.27–1.49 (m, 14H), 1.60 (s,
3H), 1.68 (s, 3H), 1.93–1.98 (m, 2H), 5.11 (t, J = 7.1 Hz,
ylsilane. IR (neat): 2953, 1645, 1497, 1454, 1247, 1048,
ꢀ
1
1
1
032, 882, 747, 698, 666 cm
;
H NMR (CDCl ): d
3
1
3
ꢀ
0.44 (ddd, J = 10.0, 6.4, 6.4 Hz, 1H), ꢀ0.05 (s, 9H),
1H); C NMR (CDCl ): d ꢀ0.1, 2.6, 8.8, 8.9, 15.6, 17.0,
3
0
7
2
8
2
.51 (ddd, J = 10.0, 3.9, 3.9 Hz, 1H), 0.59 (ddd, J = 7.3,
.3, 3.9 Hz, 1H), 1.33–1.40 (m, 1H), 1.46–1.62 (m, 6H),
.03 (t, J = 5.1 Hz, 2H), 2.20–2.30 (m, 2H), 4,51 (d,
25.7, 28.0, 29.3, 29.6, 29.7, 29.9, 30.4, 32.3, 124.9, 131.1.
Anal. Calc. for C H Si: C, 77.06; H, 12.93. Found: C,
1
8
36
76.89; H, 13.10%.
7-Trimethylsilylbicyclo[4.1.0]heptan-2-ol (15). IR (nujol):
1
3
.8 Hz, 1H); C NMR (CDCl ): d ꢀ2.3, 6.7, 10.8, 13.5,
3
ꢀ
1 1
6.9, 27.7, 28.5, 29.1, 36.8, 126.3, 138.0. Anal. Calc. for
1248, 835 cm ; H NMR (CDCl ): d ꢀ0.42 (dd, J = 6.7,
3
C H Si: C, 74.92; H, 11.61. Found: C, 74.96; H, 11.63%.
6.7 Hz, 1H), ꢀ0.05 (s, 9H), 1.02–1.21 (m, 5H), 1.36–1.45
1
3
24
[
cis-2-(Cyclohexylidenemethyl)cyclopropyl]trimethylsi-
(m, 2H), 1.58–1.65 (m, 1H), 1.89–1.90 (m, 1H), 4.18
1
3
lane. IR (neat): 2927, 2853, 1447, 1247, 833, 751, 689,
(ddd, J = 8.6, 5.6, 5.6 Hz, 1H); C NMR (CDCl ): d
3
ꢀ
1 1
6
7
1
6
2
48 cm ; H NMR (CDCl ): d ꢀ0.17 (ddd, J = 9.8, 9.8,
ꢀ2.4, 7.0, 17.4, 20.7, 22.5, 23.6, 29.5, 67.6. Elemental
analysis was conducted with a trimethylsilyl ether of
7-trimethylsilylbicyclo[4.1.0]heptan-2-ol. Anal. Calc. for
C H OSi : C, 60.87; H, 11.00. Found: C, 60.83; H, 10.73%.
3
.8 Hz, 1H), 0.00 (s, 9H), 0.31 (ddd, J = 7.8, 4.9, 3.7 Hz,
H), 0.96 (ddd, J = 9.8, 7.6, 3.4 Hz, 1H), 1.48–1.58 (m,
H), 1.70–1.75 (m, 1H), 2.03 (t, J = 5.6 Hz, 2H), 2.18–
1
3
28
2
1
3
.31 (m, 2H), 4,68 (d, J = 9.0 Hz, 1H); C NMR (CDCl3):
Typical procedure for the synthesis of pinacol (2-benzoxy-
1-cyclopropyl)boronate (17). To a greenish gray suspen-
d ꢀ0.5, 5.2, 11.2, 14.2, 26.9, 27.5, 28.4, 28.9, 37.0, 123.7,
+
1
(
39.6; EI MS m/z (%): 208 (M , 4), 134 (11), 92 (8), 73
sion of CrCl (0.98 g, 8.0 mmol) in dry, oxygen-free THF
2
+
100). HRMS (EI) m/z calcd. for (M ) C H Si
(12 mL) was added TMEDA (0.93 g, 8.0 mmol) at 25 ꢁC
and the resulting light blue mixture was stirred at 25 ꢁC
1
3
24
2
08.1647, found 208.1646.

528
K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
for 15 min. A solution of allyl benzyl ether (0.15 g,
.0 mmol) in THF (2 mL) and a solution of pinacol dic-
hloromethylboronic ester (0.42 g, 2.0 mmol) and LiI
0.54 g, 4.0 mmol) in THF (3 mL) was added successively
to the suspension at 25 ꢁC. The mixture was stirred at
5 ꢁC for 24 h, and the color changed gradually to dark
brown while stirring. The mixture was poured into water
trol of Dynamic Complexes’’) from the Ministry of
Education, Culture, Sports, Science and Technology of Ja-
pan, and Nagase Science Foundation are gratefully
acknowledged.
1
(
2
References
(
(
10 mL). This mixture was extracted with ether
3 · 10 mL), and the organic extracts were dried over anhy-
[
1] (a) E. Piers, P.D. Coish, Synthesis (1995) 47;
b) R.A. Moss, B. Wilk, K. Krogh-Jespersen, J.D. Westbrook, J.
Am. Chem. Soc. 111 (1989) 6729;
c) K. Yachi, H. Shinokubo, K. Oshima, Angew. Chem., Int. Ed. 37
(1998) 2515;
(
drous magnesium sulfate and concentrated. Purification by
column chromatography on silica gel (hexane–ethyl ace-
tate, 50:1) gave the desired cyclopropylboronic ester. Ana-
lytical samples of trans- and cis-isomers were collected by
recycling preparative HPLC.
(
(
(
(
d) A.B. Charette, A. Gagnon, J.F. Fournier, J. Am. Chem. Soc. 124
2002) 386;
e) R. Mathias, P. Weyerstahl, Chem. Ber. 112 (1979) 3041.
Pinacol (trans-2-benzyloxy-1-cyclopropyl)boronate (trans-
7).IR (neat): 2977, 2930, 2857, 1496, 1455, 1439, 1413,
[
2] N.C. Yang, T.A. Marolewski, J. Am. Chem. Soc. 90 (1968) 5644;
J. Nishimura, J. Furukawa, J. Chem. Soc., Chem. Commun. (1971)
1375;
1
1
6
6
390, 1372, 1319, 1223, 1166, 1145, 1092, 857, 736,
ꢀ
1
1
S. Miyano, H. Hashimoto, Bull. Chem. Soc. Jpn. 47 (1974) 1500;
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E.V. Dehmlow, J. Soufi, H.-G. Stammler, B. Neumann, Chem. Ber.
97 cm
;
H NMR (CDCl ): d ꢀ0.24 (dt, J = 5.6,
3
.1 Hz, 1H), 0.53–0.57 (m, 1H), 0.75–0.79 (m, 1H), 1.22
(
s, 12H), 1.31–1.37 (m, 1H), 3.24 (dd, J = 10.3, 7.1 Hz,
1
26 (1993) 499.
1
7
2
H), 3.46 (dd, J = 10.3, 6.1 Hz, 1H), 4.48–4.57 (m, 2H),
[
[
3] (a) For reviews, see: W.P. Weber, Silicon Reagents for Organic
Synthesis, Springer, Berlin, 1983, pp. 159–163;
1
3
.22–7.36 (m, 5H); C NMR (CDCl ): d 9.5, 17.5, 24.6,
3
(
(
b) L.A. Paquette, Chem. Rev. 86 (1986) 733;
c) A. Krief, Top. Curr. Chem. 135 (1987) 1.
4.9, 71.9, 72.5, 83.0, 127.4, 127.7, 128.2. Anal. Calc. for
C H BO : C, 70.85; H, 8.74. Found: C, 70.84; H, 8.90%.
1
7
25
3
4] (a) D. Seyferth, H.M. Cohen, Inorg. Chem. 1 (1962) 913;
b) H. Sakurai, A. Hosomi, M. Kumada, Tetrahedron Lett. 26 (1985)
01;
(c) M. Ahra, M. Grignon-Dubois, J. Dunoges, J. Organomet. Chem.
71 (1984) 15;
d) K. Tamao, T. Nakajima, M. Kumada, Organometallics 3 (1984)
655;
Pinacol (cis-2-benzyloxy-1-cyclopropyl)boronate (cis-
7). IR (neat): 2978, 2931, 2857, 1455, 1427, 1389, 1370,
(
3
1
ꢀ1
1
1
319, 1216, 1166, 1146, 1098, 858, 737, 698 cm ; H
2
(
1
NMR (CDCl ): d ꢀ008 (ddd, J = 16.1, 9.3, 7.1 Hz, 1H),
3
0
.53 (ddd, J = 6.8, 5.4, 3.7 Hz, 1H), 0.87 (ddd, J = 9.0,
7
.8, 3.6 Hz, 1H), 1.19 (s, 12H), 1.38–1.48 (m, 1H), 3.44
(
(
e) R.A. Olofson, D.H. Hoskin, K.D. Lotts, Tetrahedron Lett. 19
1978) 1677;
(
dd, J = 10.0, 7.8 Hz, 1H), 3.58 (dd, J = 10.0, 7.1 Hz, 1H),
4
7
7
.49 (d, J = 11.7 Hz, 1H), 4.53 (d, J = 11.7 Hz, 1H), 7.22–
(f) D. Seyferth, A.W. Dow, H. Menzel, T.C. Flood, J. Am. Chem.
Soc. 90 (1968) 1080;
1
3
.36 (m, 5H); C NMR (CDCl ): d 9.6, 17.1, 24.6, 72.3,
3
(
(
g) A.J. Ashe, J. Am. Chem. Soc. 95 (1973) 8181;
h) R.T. Taylor, L.A. Paquette, J. Org. Chem. 43 (1978) 242.
4.7, 82.9, 126,9, 127.4, 127.6, 128.2, 128.3. Anal. Calc. for
C H BO : C, 70.85; H, 8.74. Found: C, 71.14; H, 8.80%.
1
7
25
3
[
5] J.E.A. Luithle, J. Pietruszka, J. Org. Chem. 64 (1999) 8287;
J. Pietruszka, A. Witt, J. Chem. Soc., Perkin Trans. 1 (2000) 4293;
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6] (a) For a review, see: W.A. Donaldson, Tetrahedron 57 (2001) 8589;
Pinacol (trans-2-decyl-1-cyclopropyl)boronate (trans-
8). IR (neat): 2978, 2924, 2854, 1457, 1420, 1388, 1370,
1
ꢀ1
1
[
[
1
315, 1217, 1147, 858, 669 cm . H NMR (CDCl ): d
3
(
b) J. Pietruszka, Chem. Rev. 103 (2003) 1051.
7] (a) A.B. Charette, A. Giroux, J. Org. Chem. 61 (1996) 8718;
b) J.P. Hildebrand, S.P. Marsden, Synlett (1996) 893;
ꢀ
0.45 (ddd, J = 10.4, 5.7, 4.7 Hz, 1H), 0.31–0.37 (m, 1H),
0
1
2
.60–0.66 (m, 1H), 0.82–0.91 (m, 4H), 1.19 (s, 12H), 1.11–
(
1
3
.36 (m, 18H); C NMR (CDCl ): d 11.4, 14.1, 18.3, 22.7,
4.6, 29.3, 29.4, 29.6, 29.7, 31.9, 35.2, 82.7. Anal. Calc. for
3
(c) A.B. Charette, R.P. De Freitas-Gil, Tetrahedron Lett. 38 (1997)
2809;
(
d) S.-M. Zhou, M.-Z. Deng, L.-J. Xia, M.-H. Tang, Angew. Chem.,
Int. Ed. 37 (1998) 2845;
e) H. Chen, M.-Z. Deng, J. Chem. Soc., Perkin Trans. 1 (2000) 1609.
C H BO : C, 74.02; H, 12.10. Found: C, 73.86; H, 12.26%.
1
9
37
2
Pinacol (cis-2-decyl-1-cyclopropyl)boronate (cis-18). IR
neat): 2978, 2924, 2854, 1457, 1438, 1412, 1389, 1371,
(
(
[
8] (a) K. Takai, K. Nitta, K. Utimoto, J. Am. Chem. Soc. 108 (1986) 7408;
(b) K. Takai, Y. Kataoka, T. Okazoe, K. Utimoto, Tetrahedron Lett.
28 (1987) 1443;
ꢀ1
1
1
316, 1218, 1147, 856, 666 cm ; H NMR (CDCl ): d
3
ꢀ
0.10–0.13 (rn. 1H), 0.35–0.42 (m, 1H), 0.72–0.77 (m,
(
c) K. Takai, N. Shinomiya, H. Kaihara, N. Yoshida, T. Moriwake,
K. Utimoto, Synlett (1995) 963;
d) K. Takai, Y. Kunisada, Y. Tachibana, N. Yamaji, E. Nakatani,
Bull. Chem. Soc. Jpn. 77 (2004) 1581.
1
1
2
3
1
H), 0.86 (d, J = 6.8 Hz, 3H), 0.97-1.15 (m, 1H), 1.11–
1
3
.37 (m, 30H). C NMR (CDCl ): d 10.9, 14.1, 18.5,
2.7, 24.5, 24.6, 25.1, 29.4, 29.6, 29.6, 29.7, 29.8, 30.3,
1.1, 31.9, 82.8. Anal. Calc. for C H BO : C, 74.02; H,
2.10. Found: C, 73.83; H, 11.83%.
3
(
1
9
37
2
[9] K. Hirabayashi, A. Mori, T. Hiyama, Tetrahedron Lett. 38 (1997)
461;
N. Imai, K. Sakamoto, H. Takahashi, S. Kobayashi, Tetrahedron
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Soc. 125 (2003) 12990;
Acknowledgments
[
[
Financial support by a Grant-in-Aid for Scientific Re-
search on Priority Areas (No. 14078219, ‘‘Reaction Con-
(b) K. Takai, M. Hirano, S. Toshikawa, Synlett (2004) 1347.

K. Takai et al. / Journal of Organometallic Chemistry 692 (2007) 520–529
529
[
[
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1
A. F u¨ rstner, Chem. Rev. 99 (1999) 991;
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1
[17] R. Beckhaus, Angew. Chem., Int. Ed. Engl. 36 (1997) 686.
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[19] (a) For the formation of cyclopropanes by reductive elimination of
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1
[
[