Hydrogenolysis of 7-phenyltricyclo[4.1.0.02,7]heptan-1- carboxylic acid. Synthesis of ketones with tricyclo[4.4.0.02,7]decane and tricyclo[5.4.0.02,8]undecane skeletons

Article abstract of DOI:10.1134/S1070428007080088

Hydrogenation of 7-phenyltricyclo[4.1.0.0^2,7]heptane-1- carboxylic acid over Raney nickel occurred in the syn-stereoselective fashion to give anti-7-phenylbicyclo[3.1.1]heptane-exo-6-carboxylic acid. The latter was used to synthesize 4,5-benzot

Full text of DOI:10.1134/S1070428007080088

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2007, Vol. 43, No. 8, pp. 1139−1143. © Pleiades Publishing, Ltd., 2007.
Original Russian Text © R.N. Zolotarev, V.V. Razin, 2007, published in Zhurnal Organicheskoi Khimii, 2007, Vol. 43, No. 8, pp. 1147−1151.
Hydrogenolysis of 7-Phenyltricyclo[4.1.0.02,7]heptan-1-carboxylic
Acid. Synthesis of Ketones with Tricyclo[4.4.0.02,7]decane
and Tricyclo[5.4.0.02,8]undecane Skeletons
R. N. Zolotarev and V. V. Razin
St. Petersburg State University, Universitetskii pr. 26, St. Petersburg, 198504 Russia
e-mail: vvrazin@mail.ru
Received November 26, 2006
Abstract—Hydrogenation of 7-phenyltricyclo[4.1.0.02,7]heptane-1-carboxylic acid over Raney nickel occurred
in the syn-stereoselective fashion to give anti-7-phenylbicyclo[3.1.1]heptane-exo-6-carboxylic acid. The latter
was used to synthesize 4,5-benzotricyclo[4.4.0.02,7]dec-4-en-3-one and two isomeric higher homologs,
5,6-benzotricyclo[5.4.0.02,8]undec-5-en-3- and -4-ones.
DOI: 10.1134/S1070428007080088
The strained bicyclobutane system undergoes
cleavage by the action of catalytically excited hydrogen.
The depth and direction of hydrogenolysis of bicyclo-
butane system depend on the substitution pattern therein
[1]. Most frequently, cleavage of two C–C bonds (usually
central and lateral) occurs simultaneously; bicyclobutane
is thus converted into butane, and tricyclo[4.1.0.02,7]-
heptane, into methylcyclohexane [2]. Examples of
hydrogenolysis with cleavage of only the C–C bond were
also reported, but this reaction pathway generally does
not predominate [3].
The structure of acid II and methyl ester III derived
therefrom was confirmed by the 1H and 13C NMR spectra
(see below).
anti-7-Phenylbicyclo[3.1.1]heptane-exo-1-carboxylic
acid (II) seemed to be very promising from the viewpoint
of obtaining strained structures in which the 6- and
7-positions of norpinane fragment are linked through
a hydrocarbon bridge. In the present communication, the
synthetic potential of acid II is illustrated by three
examples. We have synthesized ketone IV having
a tricyclo[4.4.0.02,7]decane skeleton and two its higher
homologs, isomeric ketones V and VI having a tricyclo-
[5.4.0.02,8]undecane skeleton (Scheme 2).
It is known that α,β-unsaturated carboxylic acids, e.g.,
cinnamic acid, can be effectively hydrogenated over
nickel–aluminum alloy in alkaline medium [4]. Taking
into account partially double character of the central
bicyclobutane C–C bond [1], 7-phenyltricyclo[4.1.0.02,7]-
heptane-1-carboxylic acid (I) may be regarded as an
analog of cinnamic acid. Therefore, we thought it to be
reasonable to apply the above reducing agent to effect
hydrogenolysis of acid I. Powdered Raney nickel (nickel–
aluminum alloy at a weight ratio of 1:1) was added in
portions under vigorous stirring to a solution of acid I in
aqueous alkali at 80–85°C. The reaction involved
exclusively the central bicyclobutane bond with strict
endo,syn stereoselectivity to produce anti-7-phenylbi-
cyclo[3.1.1]heptane-exo-6-carboxylic acid (II) as the
only product in almost quantitative yield* (Scheme 1).
For preliminary Communication, see [5].
To obtain ketone IV, acid II was converted into the
corresponding acyl chloride VII which was subjected to
intramolecular acylation in the presence of SnCl4 as
catalyst. Treatment of acyl chloride VII with diazo-
methane gave diazo ketone VIII which reacted with
hydrogen chloride, yielding chloro ketone IX. Ketone V
Scheme 1.
3
4
5
2
1
Ni/Al
_OH
H
H
7
6
CO2H
Ph
Ph
CO2H
I
II
1139

ZOLOTAREV, RAZIN
1140
Scheme 2.
CH2N2
SOCl2
II
Ph
COCl
VII
Ph
CO2CH3
III
CH2N2
SnCl4
Rh(OAc)2
N2
Ph
O
O
O
VIII
V
TiCl4
IV
Ag2O / H2O
HCl
(1) SOCl2
(2) SnCl4
Ph
Cl
Ph
O
CO2H
X
O
IX
VI
was synthesized by both deazotization of compound VIII
by the action of rhodium acetate and by intramolecular
alkylation of IX in the presence of titanium(IV) chloride.
Finally, ketone VI was prepared by intramolecular
acylation of acid X which was obtained in turn by the
Arndt–Eistert reaction from acid II through intermediate
diazo ketone VIII. All compounds II–X were
characterized by the 1H and 13C NMR spectra.
a strong evidence in favor of the assumed configuration
of molecules II, III, and VII–X is provided by the
multiplicities of the 6-H and 7-H signals. In all cases,
these signals appear as two doublets (in the spectrum of
X the 6-H signal is a doublet of triplets) due to long-
range spin–spin coupling between nonequivalent 6-H and
7-H protons (W-coupling [7]).
Useful information was also obtained from the
13C NMR spectra of bicyclic compounds II, III, and VII–
X. In each case, we observed five carbon signals (two of
which had a double intensity) belonging to the norpinane
fragment; their position was weakly sensitive to the
substituent nature on C6. As above, an exception was
compound X whose C6 signal was displaced by about
5 ppm upfield due to remoteness of the carbonyl group.
Both bicyclic compounds II, III, and VII–X and
benzo-fused tricyclic ketones IV–VI formally belong to
the exo-6-anti-7-disubstituted bicyclo[3.1.1]heptane
series. In the 1H NMR spectra of bicyclic derivatives II,
III, and VII–X, respective protons of the bicyclo-
[3.1.1]heptane skeleton have almost similar chemical
shifts. An exception is compound X; as might be
1
expected, the 1-H/5-H and 6-H signals in its H NMR
The trimethylene bridges in benzo-fused tricyclic
ketones IV–VI, as well as in bicyclic compounds II, III,
VII–X, were characterized by almost similar chemical
shifts and multiplicities of signals of the corresponding
protons and carbon atoms in the 1H and 13C NMR spectra.
Differences were observed in the spectral patterns for
spectrum appear in a stronger field. Aspecific feature of
the above compounds is that the 1-H/5-H signal is
a broadened singlet since all vicinal coupling constant
for those protons are fairly small (J ≈ 0–1 Hz) [6]. Finally,
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HYDROGENOLYSIS OF 7-PHENYLTRICYCLO[4.1.0.02,7]HEPTAN-1-CARBOXYLIC ACID.
1141
the cyclobutane fragment in going from bicyclic
compounds II, III, and VII–X to tricyclic ketones IV–
VI; these differences resulted from incorporation of the
norpinane fragment into tricyclic structure and change
of the orientation of the aromatic ring. Some specificity
is intrinsic to ketone IV (but not to V or VI): in the
1H NMR spectrum of IV, two nonequivalent protons
structurally analogous to 6-H and 7-H in bicyclic
compounds II, III, and VII–X gave rise to one broadened
singlet because of accidental almost complete co-
incidence of their chemical shifts. In the 13C NMR
spectra of IV–VI, two signals from carbon atoms of the
cyclobutane fragment were displaced downfield by about
10 ppm relative to the respective signals of bicyclic
compounds II, III, and VII–X.
Methyl anti-7-phenylbicyclo[3.1.1]heptane-exo-6-
carboxylate (III) was synthesized by adding a solution
of diazomethane in diethyl ether to a solution of acid II
in diethyl ether until the mixture turned persistently
yellow. The solvent was removed, and the residue was
recrystallized from hexane. Yield nearly quantitative, mp
1
27°C, Rf 0.71 (hexane–diethyl ether, 4:1). H NMR
spectrum, δ, ppm: 1.85–2.05 m (2H, 3-H), 2.16–2.30 m
(4H, 2-H, 4-H), 2.45 d (1H, 6-H, J = 4.5 Hz), 2.97 d (1H,
7-H, J = 4.5 Hz), 3.14 br.s (2H, 1-H, 5-H), 3.23 s (3H,
OCH3), 7.11–7.21 m (1H, Harom), 7.25–7.35 m (4H,
Harom). 13C NMR spectrum, δC, ppm: 15.8 (C3); 30.8 (C2,
C4); 41.3 (C1, C5); 47.0 (C6); 49.5 (C7); 51.0 (OCH3);
125.5, 127.1, 127.7, 141.8 (Carom); 175.0 (C=O). Found,
%: C 78.29; H 7.80. C15H18O2. Calculated, %: C 78.23;
H 7.88.
EXPERIMENTAL
4,5-Benzotricyclo[4.4.0.02,7]dec-4-en-3-one (IV).
A solution of 0.52 g (2 mmol) of anhydrous tin(IV)
chloride in 5 ml of benzene was added in one portions to
a solution of 0.47 g (2 mmol) of acyl chloride VII in
10 ml of anhydrous benzene. The mixture was stirred
and kept for 6 h at 25°C, 20 ml of 5% hydrochloric acid
was added, and the mixture was vigorously stirred. The
organic phase was separated, washed in succession with
water (3×10 ml), a 5% solution of sodium hydrogen
carbonate (3×10 ml), and water again (2×10 ml), and
dried over sodium sulfate. The solvent was removed under
reduced pressure, and the residue was recrystallized from
hexane. Yield 0.32 g (81%), mp 41°C, Rf 0.73 (hexane–
1
The H and 13C NMR spectra were measured from
solutions on in CDCl3 on a Bruker DPX–300
spectrometer at 300.13 and 75.47 MHz, respectively. The
elemental compositions were determined on Hewlett–
Packard HP-185B CHN analyzer. Analytical thin-layer
chromatography was performed on Silufol UV-254
plates. The products were isolated and purified by
column chromatography on silica gele L (40–100 μm,
Chemapol). 7-Phenyltricyclo[4.1.0.02,7]heptane-1-
carboxylic acid (I) was synthesized according to the
procedure described in [8].
anti-7-Phenylbicyclo[3.1.1]heptane-exo-6-
carboxylic acid (II). Acid I, 6.42 g (0.03 mol), was
dissolved in a solution of 40 g (1 mol) of sodium
hydroxide in 300 ml of water, the mixture was heated to
80–85°C, and 13.5 g (0.25 mol of Al) of Raney nickel
was added in portions under stirring over a period of
1.5 h. The mixture was stirred for 3 h, the heating bath
was removed, and the mixture was diluted with 200 ml
of water and filtered. The filtrate was cooled and
acidified to pH 1 by adding 15% hydrochloric acid under
stirring. The precipitate was filtered off, thoroughly
washed with water, and dried in a vacuum desiccator.
Yield 6.23 g (96%), mp 117°C (from hexane). 1H NMR
spectrum, δ, ppm: 1.82–2.02 m (2H, 3-H), 2.12–2.28 m
(4H, 2-H, 4-H), 2.49 d (1H, 6-H, J = 4.5 Hz), 2.94 d
(1H, 7-H, J = 4.5 Hz), 3.09 br.s (2H, 1-H, 5-H), 7.12–
7.40 m (5H, Harom), 10.37 br.s (1H, CO2H). 13C NMR
spectrum, δC, ppm: 15.7 (C3); 30.9 (C2, C4); 41.0 (C1,
C5); 46.8 (C6); 49.9 (C7); 125.6, 127.1, 127.8, 141.4
(Carom); 180.8 (C=O). Found, %: C 77.89; H 7.51.
C14H16O2. Calculated, %: C 77.75; H 7.46.
1
diethyl ether, 1:1). H NMR spectrum, δ, ppm: 1.82–
1.95 m (2H, 9-H), 1.97–2.21 m (4H, 8-H, 10-H),
2.89 br.s (2H, 2-H, 6-H), 2.98 br.s (2H, 1-H, 7-H), 7.24 d
(1H, Harom, J = 8.0 Hz), 7.33 t (1H, Harom, J = 8.0 Hz),
7.43 t (1H, Harom, J = 8.0 Hz), 7.96 d (1H, Harom
,
J = 8.0 Hz). 13C NMR spectrum, δC, ppm: 16.0 (C9);
28.7 (C8, C10); 47.0 (C6); 53.7 (C1, C7); 56.9 (C2); 125.1,
126.1, 126.8, 129.3, 133.0, 151.3 (Carom); 201.2 (C=O).
Found, %: C 84.75; H 7.15. C14H14O. Calculated, %: C
84.81; H 7.12.
5,6-Benzotricyclo[5.4.0.02,8]undec-5-en-3-one (V).
a. Diazo ketone VIII, 0.24 g (1 mmol), was dissolved in
30 ml of benzene, 10 mg of rhodium(II) acetate was
added, and the mixture was heated for 1 h under reflux
(until the initial diazo ketone disappeared according to
the TLC data). The solvent was removed under reduced
pressure, and the residue was purified by flash
chromatography on silica gel. Yield 0.14 g (68%), mp
31°C (from ethanol), Rf 0.81 (hexane–diethyl ether, 1:1).
1H NMR spectrum, δ, ppm: 1.84–1.98 m (2H, 10-H),
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 43 No. 8 2007

ZOLOTAREV, RAZIN
1142
2.02–2.20 m (4H, 9-H, 11-H), 2.78 d (1H, 7-H,
J = 4.4 Hz), 2.92 d (1H, 2-H, J = 4.4 Hz), 3.01 br.s (2H,
1-H, 8-H), 3.58 s (2H, 4-H), 7.11–7.24 m (2H, Harom),
7.33 t (1H, Harom, J = 7.6 Hz), 7.43 d (1H, Harom, J =
7.6 Hz). 13C NMR spectrum, δC, ppm: 16.4 (C10); 31.6
(C9, C11); 46.3 (C4); 48.8 (C7); 54.0 (C1, C8); 61.8 (C2);
124.1, 125.7, 126.8, 128.4, 138.7, 142.0 (Carom); 211.7
(C=O). Found, %: C 84.73; H 7.67. C15H16O. Calculated,
%: C 84.87; H 7.60.
anti-7-Phenylbicyclo[3.1.1]heptane-exo-6-
carbonyl chloride (VII).Asolution of 2.38 g (20 mmol)
of freshly distilled thionyl chloride in 10 ml of benzene
was carefully added to 2.16 g (10 mmol) of acid II, and
the mixture was stirred for 4 h at room temperature.
Volatile components were removed under reduced
pressure, 50 ml of hexane was added to the residue, the
mixture was filtered, and the filtrate was evaporated to
a volume of ~10 ml. After prolonged keeping in
a refrigerator (–5°C), colorless crystals of acyl chloride
VII separated and were filtered off. Yield 1.86 g (79%),
b. A solution of 0.19 g (1 mmol) of anhydrous
titanium(IV) chloride in 5 ml of benzene was added in
one portion to a solution of 0.25 g (1 mmol) of chloro
ketone IX in 10 ml of benzene, and the mixture was
stirred for 2 h at room temperature (until the initial chloro
ketone disappeared according to the TLC data). The
mixture was then treated with 10 ml of 5% hydrochloric
acid and vigorously stirred. The organic layer was
separated, washed in succession with water (4×10 ml),
a 5% solution of sodium hydrogen carbonate (3×10 ml),
and water again (2×10 ml), and dried over sodium
sulfate. The solvent was removed under reduced pressure,
and the residue was purified by flash chromatography
on silica gel. Yield 0.11 g (52%).
5,6-Benzotricyclo[5.4.0.02,8]undec-5-en-4-one (VI).
A solution of 0.24 g (2 mmol) of freshly distilled thionyl
chloride in 5 ml of benzene was carefully added to 0.25
g (1 mmol) of acid X, and the mixture was stirred for 4 h
at room temperature. Volatile components were removed
under reduced pressure, the residue was dissolved in 5 ml
of anhydrous benzene, and a solution of 0.27 g (1 mmol)
of anhydrous tin(IV) chloride in 5 ml of benzene was
added. The mixture was stirred for 6 h at room
temperature, 10 ml of 5% hydrochloric acid was added,
and the organic layer was separated, washed in
succession with water (3×5 ml), a 5% solution of sodium
hydrogen carbonate (3×5 ml), and water again (2×5 ml),
and dried over sodium sulfate. Yield 0.15 g (71%), mp
38°C (from ethanol), Rf 0.76 (hexane–diethyl ether, 1:1).
1H NMR spectrum, δ, ppm: 2.02–2.13 m (2H, 10-H),
2.15–2.24 m (4H, 9-H, 11-H), 2.30 d.t (1H, 2-H, J = 4.5,
8.0 Hz), 2.38 d (2H, 3-H, J = 8.0 Hz), 2.48 d (1H, 7-H,
1
mp 47°C (from hexane). H NMR spectrum, δ, ppm:
1.86–2.07 m (2H, 3-H), 2.18–2.34 m (4H, 2-H, 4-H),
2.47 d (1H, 6-H, J = 4.5 Hz), 3.03 d (1H, 7-H, J =
4.5 Hz), 3.18 br.s (2H, 1-H, 5-H), 7.12–7.45 m (5H,
Harom). 13C NMR spectrum, δC, ppm: 16.0 (C3); 31.1 (C2,
C4); 41.6 (C1, C5); 47.1 (C6); 49.6 (C7); 125.4, 127.2,
127.9, 142.0 (Carom); 167.2 (C=O). Found, %: C 71.81;
H 6.52. C14H15ClO. Calculated, %: C 71.64; H 6.44.
2-Diazo-1-(exo-7-phenylbicyclo[3.1.1]heptan-anti-
1-yl)ethanone (VIII). A round-bottom flask equipped
with a pressure-relief valve was charged with a solution
of 2.35 g (10.0 mmol) of acyl chloride VII in 30 ml of
anhydrous diethyl ether. A solution of 1.26 g (30 mmol)
of diazomethane in diethyl ether was carefully added,
and the mixture was kept first for 2 h at 0°C and then for
12 h at room temperature. The solvent and traces of
diazomethane were removed under reduced pressure
(water-jet pump). The residue, a bright yellow oily
substance (2.4 g, ~100%) was used in further syntheses
without additional purification.An analytical sample was
obtained by purification of the crude product by flash
chromatography on silica gel L (40–100 µm). Light
yellow oily liquid, Rf 0.17 (hexane–diethyl ether, 1:1).
1H NMR spectrum, δ, ppm: 1.82–2.08 m (2H, 3-H), 2.12–
2.32 m (4H, 2-H, 4-H), 2.48 d (1H, 6-H, J = 4.6 Hz),
2.96 d (1H, 7-H, J = 4.6 Hz), 3.08 br.s (2H, 1-H, 5-H),
5.05 br.s (1H, CHN2), 7.11–7.22 m (1H, Harom), 7.24–
7.35 m (4H, Harom). 13C NMR spectrum, δC, ppm: 15.8
(C3); 30.8 (C2, C4); 41.2 (C1, C5); 46.7 (C6); 49.0 (C7);
53.6 (CN2); 126.1, 127.1, 128.2, 141.2 (Carom); 203.9
(C=O). Found, %: C 75.05; H 6.65; N 11.57. C15H16N2O.
Calculated, %: C 74.94; H 6.71; N 11.70.
J = 4.5 Hz), 2.59 br.s (2H, 1-H, 8-H), 7.18 d (1H, Harom
,
J = 7.9 Hz), 7.31 t (1H, Harom, J = 7.9 Hz), 7.44 t (1H,
Harom, J = 7.9 Hz), 7.98 d (1H, Harom, J = 7.9 Hz).
13C NMR spectrum, δC, ppm: 16.3 (C10); 31.6 (C9, C11);
45.7 (C3); 48.7 (C2); 52.5 (C1, C8); 53.1 (C7); 125.9,
127.1, 127.4, 131.4, 133.8, 151.0 (Carom); 202.9 (C=O).
Found, %: C 84.70; H 7.71. C15H16O. Calculated, %:
C 84.87; H 7.60.
2-Chloro-1-(exo-7-phenylbicyclo[3.1.1]heptan-
anti-1-yl)ethanone (IX). Diazo ketone VIII, 0.240 g
(1 mmol), was dissolved in 10 ml of methylene chloride,
2 ml of a saturated solution of HCl in methylene chloride
was added, and the mixture was stirred for 2 h at room
temperature (until the initial diazo ketone disappeared
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HYDROGENOLYSIS OF 7-PHENYLTRICYCLO[4.1.0.02,7]HEPTAN-1-CARBOXYLIC ACID.
1143
according to the TLC data). The mixture was washed
with water (3×10 ml) and dried over sodium sulfate.
Yield 0.22 g (91%), mp 49°C (from ethanol), Rf 0.66
(hexane–diethyl ether, 2:1). 1H NMR spectrum, δ, ppm:
1.84–1.97 m (2H, 3-H), 2.10–2.31 m (4H, 2-H, 4-H),
2.53 d (1H, 6-H, J = 4.6 Hz), 2.91 d (1H, 7-H, J =
4.6 Hz), 3.19 br.s (2H, 1-H, 5-H), 4.67 s (1H, CH2Cl),
7.05–7.32 m (5H, Harom). 13C NMR spectrum, δC, ppm:
16.1 (C3); 31.3 (C2, C4); 41.8 (C1, C5); 46.9 (C6); 50.0
(C7); 51.2 (CH2Cl); 126.2, 127.4, 128.4, 141.1 (Carom);
204.4 (C=O). Found, %: C 72.54; H 6.81. C15H17ClO.
Calculated, %: C 72.43; H 6.89.
(2H, 1-H, 5-H), 3.00 d (1H, 7-H, J = 4.4 Hz), 7.14–
7.42 m (5H, Harom). 13C NMR spectrum, δC, ppm: 15.6
(C3); 31.8 (C2, C4); 37.1 (CH2CO); 41.5 (C1, C5); 41.6
(C6); 47.4 (C7); 125.3, 126.7, 128.3, 144.5 (Carom); 179.4
(C=O). Found, %: C 78.34; H 7.93. C15H18O2.
Calculated, %: C 78.23; H 7.88.
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anti-2-(exo-7-Phenylbicyclo[3.1.1]hept-6-yl)acetic
acid (X). A solution of 0.48 g (2 mmol) of diazo ketone
VIII in 10 ml of dioxane was added dropwise under
stirring to a mixture of 0.46 g (2 mmol) of freshly
prepared silver oxide, 0.5 g of Na2CO3, and 0.3 g of
NaHSO3 in 20 ml of water, heated to 50–60°C. The
mixture was then stirred for 2 h, raising the temperature
to 90–100°C (disappearance of the initial diazo ketone
was monitored by TLC). The solution was cooled, diluted
with water, and acidified to pH 1 with dilute nitric acid,
and the precipitate was filtered off, washed with water,
and dried in a vacuum desiccator. Yield 0.30 g (66%),
mp 102°C (from hexane), Rf 0.42 (hexane–diethyl ether,
1:1). 1H NMR spectrum, δ, ppm: 1.87–1.99 m (2H, 3-
H), 2.10 d.t (1H, 6-H, J = 4.4, 8.0 Hz), 2.13–2.26 m (4H,
2-H, 4-H), 2.31 d (2H, CH2CO, J = 8.0 Hz), 2.67 br.s
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RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 43 No. 8 2007