1-Ferrocenylcyclopropene and 1-ferrocenylcyclopropyl cation

Article abstract of DOI:10.1016/S0022-328X(02)02037-5

Dehydrobromination of cis and trans isomers of 1-bromo-2-ferrocenylcyclopropanes affords 1-ferrocenylcyclopropene. Its protonation with HBF₄ results in 1-ferrocenylcyclopropylium tetrafluoroborate, which alkylates N,N-dimethylaniline in para po

Full text of DOI:10.1016/S0022-328X(02)02037-5

Journal of Organometallic Chemistry 665 (2003) 23Á28
/
www.elsevier.com/locate/jorganchem
1-Ferrocenylcyclopropene and 1-ferrocenylcyclopropyl cation
Tatiana Klimova a, Elena I. Klimova a,*, Marcos Mart´ınez Garc´ıa b,
Cecilio Alvarez Toledano b, Ruben Alfredo Toscano b
a Facultad de Qu´ımica, Universidad Nacional Auto´noma de Me´xico, Cd. Universitaria, Coyoaca´n, C.P. 04510, Mexico D.F., Mexico
b Instituto de Qu´ımica, Universidad Nacional Auto´noma de Me´xico, Cd. Universitaria, Coyoaca´n, C.P. 04510, Mexico D.F., Mexico
Received 30 July 2002; received in revised form 15 October 2002; accepted 15 October 2002
Abstract
Dehydrobromination of cis and trans isomers of 1-bromo-2-ferrocenylcyclopropanes affords 1-ferrocenylcyclopropene. Its
protonation with HBF4 results in 1-ferrocenylcyclopropylium tetrafluoroborate, which alkylates N,N-dimethylaniline in para
position to yield 1-(p-dimethylaminophenyl)-1-ferrocenylcyclopropane. 1-Ferrocenylcyclopropene reacts with 1,3-diphenylisoben-
zofuran to give the classical [4ꢀ2]-cycloaddition product. Its structure as exo-2-ferrocenyl-1,5-diphenyl-6,7-benzo-8-oxatricy-
/
clo[3.2.1.02,4]oct-6-ene was established based on the data from X-ray diffraction analysis.
# 2002 Elsevier Science B.V. All rights reserved.
Keywords: Cyclopropene; Cyclopropane; [4ꢀ2]-Cycloadduct; Protonation; Alkylation; Cyclopropyl cation; Ferrocene
/
1. Introduction
at ꢁ
/
80 8C underwent virtually no small-ring opening
when kept at ꢁ
/
40 8C.
All the available literature data suggest that the
properties of three-membered carbocycles change upon
introduction of a ferrocenyl substituent. Thus properties
of ferrocenylcyclopropanes and ferrocenylcyclopropenes
are distinctly different from those of unsubstituted
carbocycles and analogous arylcyclopropanes and ar-
The effect of ferrocenyl substituents in small rings is
rather well pronounced and their influence is often
highly selective, therefore, it was of interest to reveal
features of the electronic interaction of the ferrocenyl
group with the small ring, which is attractive from both
the theoretical point of view and in connection with a
search for selective reactions of cyclopropanes and
cyclopropenes.
ylcyclopropenes [1Á7]. In particular, 3-p-tolyl-1,2,3-
/
triferrocenylcyclopropene undergoes small-ring opening
followed by cyclization involving ferrocenyl and aryl
fragments when heated in chloroform solution at 50 8C
[3], while 3-phenyl- and 3-naphthyl-3-ferrocenylcyclo-
Chemical behavior of 3-alkyl- and 3-aryl-3-ferroce-
nylcyclopropenes has been investigated in recent years in
fairly full detail [4,5,9Á12]. At the same time, chemistry
/
of monosubstituted ferrocenylcyclopropenes with the
ferrocenyl substituent in positions 1 or 3 of the small
ring remains unexplored.
propenes rearrange analogously at Â80 8C to give the
/
corresponding indene derivatives [4,5]. Isomerization of
Z-1,2-diferrocenyl- and Z-1-aryl-2-ferrocenylcyclopro-
panes into the corresponding stable E isomers occurred
extremely fast, these were formed quantitatively during
1
registration of the H-NMR spectra [6,7].
2. Results and discussion
The enhancement of the stability of electron-deficient
centers vicinal to the ferrocenyl group is also note-
worthy. The first long-lived a-ferrocenylcyclopropyl
cation that was observed by Olah and co-workers [8]
In continuation of our investigations into the chem-
istry of ferrocenylcyclopropenes, we undertook attempts
at the preparation of 1- and 3-ferrocenylcyclopropenes
(1a and 1b). Presumably, a mixture of these compounds
had to be obtained upon dehydrobromination of 1-
bromo-2-ferrocenylcyclopropane (2) (Scheme 1).
* Corresponding author. Tel./fax: ꢀ
/
52-56225366
E-mail address: klimova@servidor.unam.mx (E.I. Klimova).
0022-328X/02/$ - see front matter # 2002 Elsevier Science B.V. All rights reserved.
PII: S 0 0 2 2 - 3 2 8 X ( 0 2 ) 0 2 0 3 7 - 5

24
T. Klimova et al. / Journal of Organometallic Chemistry 665 (2003) 23Á28
/
Scheme 1.
Scheme 3.
The starting monobromides 2 were prepared as
follows (Scheme 2).
Dibromocyclopropanation of vinylferrocene pro-
ceeded without any difficulties, and 1,1-dibromo-2-
ferrocenylcyclopropane (3) was isolated in high yield
(70Á80%). This was reduced with a mixture of ethyl-
/
magnesium chloride and titanium isopropoxide [11] to
give a mixture of cis- and trans-1-bromo-2-ferrocenyl-
cyclopropanes (2a and 2b) in a 1:1 ratio in 58% yield
together with a side product, viz., ferrocenylcyclopro-
Scheme 4.
Its structure was established based on the spectro-
scopic data (see Section 3). The 1H- and 13C-NMR
spectra correspond to a single structural isomer, which
pane (4) (Â20%). These could easily be separated by
/
column chromatography on Al2O3. NMR spectra of the
products obtained proved unambiguously their struc-
tures (see Section 3).
attests to the stereospecific character of the DielsÁ
reaction.
/
Alder
Single crystals of the adduct 5 prepared by crystal-
lization from hexane were studied using X-ray diffrac-
tion analysis, which showed that compound 5 has the
structure of exo-2-ferrocenyl-1,5-diphenyl-6,7-benzo-8-
oxatricyclo[3.2.1.02,4]oct-6-ene. The general view of the
molecule 5 is shown in Fig. 1. The principal geometrical
parameters are listed in Table 1.
The assignment of the isomeric monobromides to the
cis and trans isomeric series has been carried out based
1
on their H-NMR spectroscopic data with account of
the previously established NMR criteria for the assign-
ment of Z and E isomers of bromo(ferrocenyl)cyclo-
propanes [4,5,9Á
11]. Thus the 1H-NMR spectrum of the
/
monobromide 2a contains two multiplets at d 0.81 and
1.34 belonging to the methylene protons. In the 1H-
NMR spectrum of the isomeric compound 2b, analo-
gous signals were present at d 1.24 and 1.42. The
difference in the chemical shifts for the methylene
We also demonstrated that the protonation of the
cyclopropene 1a with HBF4 etherate at ꢁ40 8C re-
/
sulted in 1-ferrocenylcyclopropyl tetrafluoroborate 6
(Scheme 5).
The salt 6 is a microcrystalline dark brown substance
protons in the isomer 2a (Ddꢂ
/
0.53 ppm) is larger
0.18 ppm), which is
stable atꢁ40 8C in an inert atmosphere for several
/
1
than that in the isomer 2b (Ddꢂ
/
hours. We managed to record its H-NMR spectrum
(for solution in CD2Cl2) which corroborated completely
the structure 6 (see Section 3).
evidence for the cis configuration of the former. Such a
regularity has previously been observed in the 1H-NMR
spectra of all Z- and E-isomeric 1-alkyl- and 1-aryl-2-
bromo-1-ferrocenylcyclopropanes studied so far [4,5,9Á
11].
We have found that the reaction of bromo(ferroce-
Like other a-ferrocenylcarbocations [13Á/16], 1-ferro-
/
cenylcyclopropyl cation 6 alkylates N,N-dimethylani-
line in the para position to give 1-(p-dimethylamino-
phenyl)-1-ferrocenylcyclopropane (7) as the only pro-
duct (Scheme 6).
nyl)cyclopropanes 2a and 2b with potassium tert-but-
oxide in DMSO affords regioselectively 1-ferrocenyl-
The absence of small-ring opening products in this
reaction suggests high stabilizing effect of the ferrocenyl
substituent with respect to the a-carbocationic center,
which imparts sufficient stability even to the cyclopropyl
cation 6. Removal of the ferrocenyl group away from
the cationic center to the b-position decreases the
stability of the cyclopropyl cations and results in
instantaneous three-membered ring opening yielding 1-
cyclopropene 1a in Â41% yield and unidentified poly-
/
meric products (Scheme 3).
The cyclopropene 1a is an orange oily compound
unstable on storage. Its structure was established based
on the data from 1H-NMR spectroscopy, elemental
analysis, and chemical transformations.
The freshly prepared 1-ferrocenylcyclopropene 1a
reacts with 1,3-diphenylisobensofuran at ambient tem-
ferrocenylallyl cations (see Refs. [4Á
/
7,9Á11]).
/
perature to give a [4ꢀ
/
2]-cycloaddition product 5
(Scheme 4).
3. Experimental
All the solvents were dried according to standard
procedures and used freshly distilled. Column chroma-
tography was carried out on alumina (Brockmann
Scheme 2.

T. Klimova et al. / Journal of Organometallic Chemistry 665 (2003) 23Á
/28
25
Fig. 1. Crystal structure of 5.
Table 1
˚
Selected bond lengths (A) and bond angles (8) for compound 5
Bond lengths, r
C(2)Ã
C(3)Ã
C(4)Ã
C(1)Ã
C(5)Ã
C(1)Ã
/
C(3)
C(4)
C(5)
C(7)
C(29)
O(8)
1.519(5)
1.522(5)
1.542(4)
1.532(5)
1.506(4)
1.458(4)
C(2)Ã
C(1)Ã
C(5)Ã
C(2)Ã
C(1)Ã
C(5)Ã
/
C(4)
C(2)
C(6)
C(19)
C(13)
O(8)
1.517(4)
1.579(4)
1.533(5)
1.492(5)
1.512(4)
1.465(4)
/
/
/
/
/
/
Scheme 6.
/
/
/
/
Bond angles, v
O(8)ÃC(1)ÃC(7)
C(7)ÃC(1)ÃC(2)
C(13)ÃC(1)ÃC(7)
C(19)ÃC(2)Ã
C(19)ÃC(2)Ã
C(4)ÃC(2)Ã
C(2)ÃC(3)Ã
C(2)ÃC(4)Ã
O(8)ÃC(5)Ã
C(6)ÃC(5)Ã
fluoroborate 6 was recorded for a solution in CD2Cl2.
The following reagents were purchased from Aldrich:
bromoform, 99%; ethylmagnesium chloride (2.0 M
solution in diethyl ether); potassium tert-butoxide,
95%; titanium(IV) isopropoxide (97%); vinylferrocene,
97%; N,N-dimethylaniline, 99.5%, and dimethyl sulfox-
ide, anhydrous, 99.8%. Tetrafluoroboric acid etherate,
/
/
100.1(2)
104.9(3)
119.8(3)
124.7(3)
118.4(3)
60.2(2)
O(8)Ã
O(8)Ã
C(13)Ã
C(19)Ã
C(3)ÃC(2)Ã
C(4)ÃC(2)Ã
C(2)ÃC(4)Ã
O(8)ÃC(5)Ã
O(8)ÃC(5)Ã
C(7)ÃC(6)Ã
/
C(1)Ã
C(1)Ã
/
C(2)
C(13)
101.1(2)
111.9(3)
116.3(3)
122.1(3)
114.6(3)
102.5(2)
102.9(3)
100.1(2)
101.6(2)
105.5(3)
/
/
/
/
/
/
/
C(1)Ã
/C(2)
/
/C(4)
/
C(2)Ã
/C(3)
/
/C(1)
/
/
C(1)
C(1)
C(5)
/
/
C(3)
C(4)
C(3)
/
/
/
/
59.9(2)
/
/
/
/
59.9(2)
111.7(3)
105.2(3)
/
/
C(6)
C(4)
C(5)
50Á52%, was purchased from Alfa AESAR.
/
/
/C(29)
/
/
The unit cell parameters and the X-ray diffraction
intensities were recorded on a Siemens P4/PC diffract-
ometer. The crystallographic data, the parameters of the
X-ray diffraction experiment, and refinements are listed
in Table 2. The structure of compound 5 was solved by
the direct method and refined by the least-squares
method in a full-matrix anisotropic approximation for
the non-hydrogen atoms.
/
/C(4)
/
/
Scheme 5.
3.1. 1,1-Dibromo-2-ferrocenylcyclopropane 3
activity III). The 1H and 13C-NMR spectra were
recorded on a Unity Inova Varian spectrometer (300
and 75 MHz) for solutions in CDCl3 with Me4Si as the
The title compound was obtained from vinylferrocene
according to the standard procedure [9], yield 70Á
/
80%,
102 8C. 1H-NMR, d: 1.69
1
internal standard, the H-NMR spectrum of the tetra-
yellow crystals, m.p. 100Á
/

26
T. Klimova et al. / Journal of Organometallic Chemistry 665 (2003) 23Á28
/
Table 2
Crystallographic data and structure refinement parameters for com-
pound 5
1-Ferrocenylcyclopropane 4, yield 0.23 g (20.5%),
yellow oil. 1H-NMR, d: 0.47Á
0.66 (1H, m, CH2),
0.76Á0.80 (1H, m, CH2), 1.00 (1H, m, CH2), 1.31 (1H,
/
/
m, CH2), 1.53 (1H, m, CH), 4.02 (4H, s, C5H4), 4.14
(5H, s, C5H5). Anal. Calcd. for C13H14Fe: C, 69.05; H,
6.24; Fe, 24.71. Found: C, 68.92; H, 6.39; Fe, 24.90%.
Data
5
Molecular formula
Formula weight
Temperature (K)
C
33H26FeO
494.39
273(2)
cis-1-Bromo-2-ferrocenylcyclopropane 2a, yield 0.38
1
g (25%), yellow crystals, m.p. 60Á
/
61 8C. H-NMR, d:
˚
Mo-Ka, radiation, l (A)
Crystal system
0.71073
triclinic
0.81 (1H, m, CH2), 1.34 (1H, m, CH2), 1.83 (1H, m,
CHFc), 3.03 (1H, m, CH), 3.92 (1H, m, C5H4), 3.95 (1H,
m, C5H4), 3.98 (1H, m, C5H4), 4.00 (5H, s, C5H5), 4.11
(1H, m, C5H4). Anal. Calcd. for C13H13BrFe: C, 51.19;
H, 4.30; Br, 26.20; Fe, 18.31. Found: C, 51.33; H, 4.12;
Br, 26.32; Fe, 18.10%.
¯
Space group
/
P1/
Unit cell dimensions
˚
a (A)
˚
9.517(2)
11.268(3)
12.528(3)
77.150(10)
75.37(2)
74.00(2)
1232.6(5)
2
b (A)
˚
c (A)
a (8)
b (8)
trans-1-Bromo-2-ferrocenylcyclopropane 2b, yield
0.40 g (26%), yellow crystals, m.p. 71Á
72 8C. 1H-
g (8)
/
3
V (A )
˚
NMR, d: 1.24 (1H, m, CH2), 1.42 (1H, m, CH2), 2.08
(1H, m, CHFc), 2.92 (1H, m, CH), 4.06 (2H, m, C5H4),
4.12 (2H, m, C5H4), 4.21 (5H, s, C5H5). Anal. Calcd. for
C13H13BrFe: C, 51.19; H, 4.30; Br, 26.20; Fe, 18.31.
Found: C, 51.40; H, 4.12; Br, 26.03; Fe, 18.55%.
Z
rcalc (g cmꢁ3
Absorption coefficient
)
1.332
0.636
(mmꢁ1
F(000)
)
516
graphite
Monochromator
u Scanning range (8)
Total number of reflections
Number of independent re-
flections
1.50Á25.00
4611
4325
/
3.3. Dehydrobromination of
bromo(ferrocenyl)cyclopropanes 2a and 2b
Rint
Goodness of fit on F2
0.0388
1.067 (full-matrix least-squares on F2)
A mixture of bromo(ferrocenyl)cyclopropane 2a (or
2b) (0.9 g, 3 mmol) and ButOK (4 mmol) in DMSO (30
Final R indices [I ꢀ
/
2s(I)]
R1ꢂ
R1ꢂ
317
/
0.0500, wR2ꢂ
/
0.1220
ml) was strirred for 6 h at Â
/
20Á25 8C. The reaction
/
R indices (all data)
Number of refinable
parameters
/
0.0769, wR2ꢂ
/
0.1420
mixture was then partitioned between benzene (100 ml)
and water (50 ml), the organic layer was washed with
water and concentrated in vacuo. Chromatography of
the residue (Al2O3, hexane) gave 1-ferrocenylcyclopro-
pene 1a, yield 0.27 g (40%) from the bromide 2a and
0.28 g (42%) from the bromide 2b, orange oil. 1H-NMR,
d: 1.00 (1H, m, CH2), 1.31 (1H, m, CH2), 1.53 (1H, m,
Residual electron density
(e Aꢁ3), rmin/rmax
Weighting scheme
ꢁ/0.303/0.404
˚
wꢂ
where Pꢂ
/
1/[s2(F02)ꢀ
/
(0.1693P)2ꢀ
2Fc2)/3
/
10.77P],
/
(F02ꢀ
/
CH), d 2.61 (2H, d, CH2, Jꢂ
C5H5), 4.04 (2H, s, C5H4), 4.06 (2H, s, C5H4), 6.62 (1H,
, Jꢂ1.8 Hz). Anal. Calcd. for C13H12Fe: C,
69.68; H, 5.40; Fe, 24.92. Found: C, 69.86; H, 5.21; Fe,
25.07%.
/
1.8 Hz), 4.02 (5H, s,
(1H, t, CH2, Jꢂ
10.8 Hz), 2.68 (1H, dd, CH2, Jꢂ
m, C5H4), 4.18 (1H, m, C5H4), 4.22 (5H, s, C5H5), 4.25
(1H, m, C5H4), 4.44 (1H, m, C5H4). Anal. Calcd. for
C13H12Br2Fe: C, 40.67; H, 3.15; Br, 41.63; Fe, 14.55.
Found: C, 40.42; H, 3.28; Br, 41.77; Fe, 14.71%.
/
7.8 Hz), 2.11 (1H, dd, CH2, Jꢂ
/
7.8,
t, CHÄ
/
/
/
7.8, 10.8 Hz), 4.03 (1H,
3.4. Reaction of cyclopropene 1a with 1,3-
diphenylisobenzofuran
A solution of cyclopropene 1a (0.34 g, 1.5 mmol) and
1,3-diphenylisobenzofuran (0.56 g, 2 mmol) in dry
benzene (50 ml) was stirred at r.t. for 48 h. The solvent
was evaporated in vacuo and the residue was chromato-
graphed (Al2O3, hexane/ether, 7:1) to give the starting
cyclopropene (0.12 g, 35%) as an orange oil and the
3.2. Reduction of the dibromide 3
A solution of EtMgCl (6 mmol) in ether and several
drops of Ti(OPri)4 were added with stirring to a solution
of the dibromide 3 (1.92 g, 5.0 mmol) in dry tetrahy-
drofuran (100 ml). The mixture was stirred for 4 h at
room temperature (r.t.) and quenched with water (50
ml). The organic layer was separated, washed with
water, dried with Na2SO4, and concentrated in vacuo.
The residue was chromatographed on alumina in hexane
and the following products were isolated:
adduct 5, yield 0.37 g (50%), pale yellow crystals, m.p.
1
210Á
/
211 8C. H-NMR, d: 1.79 (1H, dd, CH, Jꢂ
/
4.8,
3.6, 6.6 Hz), 2.29 (1H,
3.6, 4.8 Hz), 3.05 (1H, m, C5H4), 3.93 (1H,
m, C5H4), 3.99 (5H, s, C5H5), 4.03 (1H, m, C5H4), 4.08
(1H, m, C5H4), 7.10Á
7.76 (14H, m, 2 C6H5, C6H4). 13C-
6.6 Hz), 1.99 (1H, dd, CH2, Jꢂ
/
dd, CH, Jꢂ
/
/

T. Klimova et al. / Journal of Organometallic Chemistry 665 (2003) 23Á
/28
27
NMR, d: 21.85 (CH2); 35.52 (CH2); 35.59 (C); 66.84,
66.95, 68.94, 70.36 (C5H4); 68.28 (C5H5); 88.07, 88.15
5. Copies of this information may be obtained free of
charge from The Director, CCDC, 12 Union Road,
(CÁ/O); 90.15 (CipsoFc); 119.47, 122.05, 125.45, 126.18,
Cambrige CB2 IEZ, UK (Fax: ꢀ44-1223-336033;
/
127.80, 127.83, 127.86, 127.92, 127.93, 127.95, 127.97,
128.35, 128.36, 128.45 (2 C6H5, C6H4); 135.54, 136.61,
148.80, 150.99 (Cipso). Anal. Calcd. for C33H26FeO: C,
80.17; H, 5.29; Fe, 11.29. Found: C, 80.29; H, 5.08; Fe,
11.42%.
e-mail: deposit@ccdc.cam.ac.uk or www: http://www.
ccdc.cam.ac.uk).
Acknowledgements
3.5. The action of tetrafluoroboric acid etherate on the
cyclopropene 1a
This work was supported by the grant CONACyT
(Mexico, grant 34862-E). We would like to thank Oscar
Salvador Yanez Munoz for the technical assistance.
˜
˜
Tetrafluoroboric acid etherate (3 ml) was added
dropwise with stirring and cooling (ꢁ
/
40 to ꢁ50 8C)
/
in an atmosphere of dry nitrogen to a solution of
compound 1a (0.25 g, 1 mmol) in dry ether (50 ml) and
References
the mixture was stirred at Â
/
ꢁ40 8C for 1 h. The
/
[1] A.J. Fry, P.S. Jain, R.L. Krieger, J. Organomet. Chem. 214 (1961)
381.
precipitate that formed was separated by decantation,
washed with several portions of cold ether (decantation)
and dried in vacuo with an external cooling. The
tetrafluoroborate 6 was obtained in a yield of 0.19 g
(61%), dark brown finely crystalline powder, decom-
[2] A.J. Fry, R.L. Krieger, I. Agranat, E. Aharon-Shalom, Tetra-
hedron Lett. 32 (1976) 4803.
[3] I. Agranat, E. Aharon-Shalom, A.J. Fry, R.L. Krieger, W.O.
Krug, Tetrahedron 35 (1979) 733.
[4] E.I. Klimova, T. Klimova Berestneva, L. Ruiz Ramirez, M.
Martinez Garcia, C. Alvarez Toledano, P.G. Espinosa, R.A.
poses at Â
170 8C. 1H-NMR, d: 1.56 (4H, br.s, 2 CH2),
/
4.28 (5H, s, C5H5), 4.35 (2H, m, C5H4), 5.72 (2H, m,
C5H4). Anal. Calcd. For C13H13BF4Fe: C, 50.06; H,
4.20; Fe, 17.90. Found: C, 49.80; H, 4.02; Fe, 18.19%.
Toscano, J. Organomet. Chem. 545Á546 (1997) 191.
/
[5] E.I. Klimova, M. Martinez Garcia, T. Klimova, C. Alvarez
Toledano, R.A. Toscano, R. Moreno Esparza, L. Ruiz Ramirez,
J. Organomet. Chem. 566 (1998) 175.
[6] (a) E.I. Klimova, V.N. Postnov, V.A. Sazonova, Dokl. Akad.
Nauk SSSR 263 (1982) 368;
3.6. Reaction of the cyclopropyl cation 6 with N,N-
dimethylaniline
(b) E.I. Klimova, V.N. Postnov, V.A. Sazonova, Dokl. Chem. 263
(1982) (English Translation).
[7] (a) E.I. Klimova, A.N. Pushin, V.A. Sazonova, Zh. Obshch.
Khim. 57 (1987) 2336;
A solution of N,N-dimethylaniline (1 ml) in dichlor-
omethane (10 ml) was added dropwise with stirring and
(b) E.I. Klimova, A.N. Pushin, V.A. Sazonova, J. Gen. Chem.
USSR 57 (1987) (English Translation).
cooling (ꢁ
solution of the salt 6 (0.15 g, 0.5 mmol) in dichlor-
omethane (20 ml). The mixture was stirred at ꢁ50 8C
/
50 8C) in a dry inert atmosphere to a
[8] G.K. Surya Pracash, H. Buchholz, V. Pracash Reddy, A. Meijere,
G.A. Olah, J. Am. Chem. Soc. 114 (1992) 1097.
[9] E.I. Klimova, L. Ruiz Ramirez, R. Moreno Esparza, T. Klimova
Berestneva, M. Martinez Garcia, N.N. Meleshonkova, A.V.
Churakov, J. Organomet. Chem. 559 (1998) 1.
/
for 30 min and quenched by addition of water (50 ml).
The organic layer was separated, washed with 5% HCl
[10] (a) E.I. Klimova, C. Alvarez Toledano, M. Martinez Garcia, J.
Gomez Lara, N.N. Meleshonkova, I.G. Bolesov, Izv. Akad.
Nauk. Ser. Khim. 652 (1996);
(2ꢃ10 ml) and water, dried with Na2SO4, and concen-
/
trated. Chromatography of the residue (Al2O3, hexane-
ether, 7:1) afforded 1-(p-dimethylaminophenyl)-1-ferro-
cenylcyclopropane 7, 0.11 g (60%), orange oil. 1H-
(b) E.I. Klimova, C. Alvarez Toledano, M. Martinez Garcia, J.
Gomez Lara, N.N. Meleshonkova, I.G. Bolesov, Russ. Chem.
Bull. 45 (1996) 613 (English Translation).
NMR, d: 1.24Á
CH3), 3.72 (2H, m, C5H4), 3.98 (2H, m, C5H4), 4.10
(5H, s, C5H5), 6.51 (2H, d, C6H4, Jꢂ8.2 Hz), 6.74 (2H,
d, C6H4, Jꢂ8.2 Hz). Anal. Calcd. for C21H23FeN: C,
/
1.32 (4H, m, 2 CH2), 3.01 (6H, s, 2
[11] E.I. Klimova, M. Martinez Garcia, T. Klimova, C. Alvarez
Toledano, R.A. Toscano, L. Ruiz Ramirez, J. Organomet. Chem.
598 (2000) 254.
/
/
[12] E.I. Klimova, M. Martinez Garcia, T. Klimova, C. Alvarez
Toledano, R.A. Toscano, L. Ruiz Ramirez, J. Organomet. Chem.
605 (2000) 89.
73.05; H, 6.71; Fe, 16.18; N, 4.06. Found: C, 72.84; H,
6.93; Fe, 16.12; N, 3.89%.
[13] (a) A.N. Nesmeyanov, V.A. Sazonova, G.I. Gudkova, L.S.
Isaeva, Izv. Akad. Nauk SSSR Ser. Khim. 2017 (1966);
(b) A.N. Nesmeyanov, V.A. Sazonova, G.I. Gudkova, L.S.
Isaeva, Bull. Acad. Sci. USSR Div. Chem. Sci. 15 (1966) (English
Translation).
4. Supplementary material
[14] (a) A.N. Nesmeyanov, V.A. Sazonova, V.N. Postnov, Izv. Akad.
Nauk SSSR Ser. Khim. (1978) 2175;
Crystallographic data for the structural analysis have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC No. 187751 for exo-2-ferrocenyl-
1,5-diphenyl-6,7-benzo-8-oxatricyclo[3.2.1.02,4]oct-6-ene
(b) A.N. Nesmeyanov, V.A. Sazonova, V.N. Postnov, Bull.
Acad. Sci. USSR, Div. Chem. Sci. 27 (1978) (English Transla-
tion).

28
T. Klimova et al. / Journal of Organometallic Chemistry 665 (2003) 23Á28
/
[15] (a) A.N. Nesmeyanov, V.A. Sazonova, V.N. Drozd, Izv. Akad.
Nauk SSSR Ser. Khim. (1965) 2061;
[16] (a) A.N. Nesmeyanov, V.N. Postnov, I.F. Leshcheva, Dokl.
Akad. Nauk SSSR 200 (1971) 858;
(b) A.N. Nesmeyanov, V.A. Sazonova, V.N. Drozd, Bull. Acad.
Sci. USSR, Div. Chem. Sci. 14 (1965) (English Translation).
(b) A.N. Nesmeyanov, V.N. Postnov, I.F. Leshcheva, Dokl.
Chem. 200 (1971) (English Translation).