SYNTHESIS OF DISPIRO[2.1.3.1]NONANE AND TRISPIRO[2.1.1.37.15.13]DODECANE
597
The extract was dried over CaCl2 and evaporated to
obtain 36 g of dibromide IX which was not subjected
to further purification. A solution of 36 g of dibromide
IX in 100 ml of ethanol was added under vigorous
stirring to a mixture of 36 g of zinc dust, 42 g of
sodium hydroxide in 150 ml of water, 300 ml of
ethanol, and 120 g of Trilon B. The mixture was stirred
for 4 h on heating, diluted with 300 ml of water, and
filtered. The filtrate was extracted with pentane, the
precipitate was washed with pentane–diethyl ether, the
washings were combined with the organic extract,
dried over MgSO4, and evaporated, and the residue
was distilled under reduced pressure. Yield 9 g (54%),
bp 77–78°C (130 mm), nD20 = 1.4535. IR spectrum
(CCl4), ν, cm–1: 3080, 2950, 2850, 1435, 1285, 1140,
The structure of hydrocarbons I and II was deter-
mined by spectral methods. The H NMR spectra of I
1
and II contained singlets at δ 0.44 and 0.46 ppm,
respectively, which belong to four methylene protons
in the cyclopropane ring. Compound I displayed in
the 13C NMR spectrum a triplet at δC 12.3 ppm (1JCH
=
162 Hz) from methylene carbon atoms in the cyclo-
propane ring and a singlet at δC 15.0 ppm from the
spiro carbon atom. The corresponding signals of tri-
1
spiro derivative II were observed at δC 11.3 (t, JCH
=
162 Hz) and 15.2 ppm (s), and signals from the other
spiro atoms were located at δC 34.6 and 39.3 ppm.
Intermediate alcohols, p-toluenesulfonates, and
bromides were not subjected to special purification,
1
and they were characterized only by H NMR spectra,
1
1120, 1035, 1015, 980. H NMR spectrum, δ, ppm:
which were consistent with the assumed structures.
0.44 s (4H), 1.84–2.28 (6H), 2.16 s (4H). 13C NMR
Diethyl dispiro[3.1.3.1]decane-2,2-dicarboxylate
(X). A solution of 36 g (0.15 mol) of diester VI in
100 ml of diethyl ether was added to a mixture of 8 g
of LiAlH4 and 200 ml of anhydrous diethyl ether on
cooling with ice. The mixture was stirred for 6 h at
room temperature and treated with 15 ml of water on
cooling with ice, and the precipitate was filtered off
and extracted with ethyl acetate in a Soxhlet apparatus
over a period of 6 h. The organic phases were com-
bined and dried over MgSO4, and the solvent was
distilled off. The residue, 28 g of spiro[3.3]heptane-
2,2-diyldimethanol (VII), was dissolved in 100 ml of
pyridine, the solution was cooled with ice, 67 g of
p-toluenesulfonyl chloride was added under stirring,
and the mixture was stirred for 2 h and left overnight.
The mixture was then poured into a mixture of ice with
hydrochloric acid, and the precipitate was filtered off
and washed with methanol. Yield of bis-sulfonate VIII
51 g. The product was added under stirring to diethyl
malonate sodium salt prepared from 6 g of sodium and
57 g of diethyl malonate in 150 ml of xylene. The
mixture was stirred for 16 h on heating, cooled, and
treated with 150 ml of water, the organic phase was
separated and dried over MgSO4, the solvent was
distilled off under reduced pressure, and the residue
was distilled in vacuo. Yield of diester X 16.5 g
(39% calculated on the initial diester VI), bp 112–
117°C (0.2 mm).
spectrum (CDCl3), δC, ppm: 12.3 t (CH2, JCH
=
162 Hz), 15.0 s (Cspiro), 16.6 t (CH2, JCH = 135 Hz),
36.0 t (CH2, JCH = 135 Hz), 39.8 s (Cspiro), 44.1 t (CH2,
JCH = 135 Hz). Mass spectrum: m/z 122 [M]+. Found,
%: C 88.07; H 11.91. C9H14. Calculated, %: C 88.45;
H 11.55.
Trispiro[2.1.1.37.15.13]dodecane (II) was synthe-
sized in a similar way. The reduction of 33 g of diester
X with 9 g of LiAlH4 gave 20 g of diol XI which was
dissolved in 100 ml of pyridine, the solution was
cooled with ice, 55 g of p-toluenesulfonyl chloride was
added, and the mixture was treated as described above
to isolate 25 g of bis-sulfonate XII. By reacting the
latter with 17 g of lithium bromide in 200 ml of anhy-
drous acetone we obtained dibromide XIII which was
dissolved (without purification) in 50 ml of ethanol,
and the solution was added under vigorous stirring to
a mixture of 18 g of zinc dust, 60 g of Trilon B, 21 g of
NaOH in 75 ml of water, and 200 ml of ethanol. The
mixture was stirred for 5 h on heating and treated as
described above. Yield of II 1.5 g (13% calculated on
the initial diester X), bp 67–69°C (15 mm), nD20
=
1.4680. IR spectrum (CCl4), ν, cm–1: 3080, 2850, 1435,
1
1280, 1130, 1080, 1015, 980. H NMR spectrum, δ,
ppm: 0.45 s (4H), 1.90–2.10 (10H), 2.17 s (4H).
13C NMR spectrum (CDCl3), δC, ppm: 11.3 t (CH2,
JCH = 162 Hz), 15.2 s (Cspiro), 16.8 t (CH2, JCH
=
135 Hz), 34.6 s (Cspiro), 35.4 t (CH2, JCH = 135 Hz),
39.3 s (Cspiro), 44.4 t (CH2, JCH = 135 Hz), 48.5 t (CH2,
JCH = 135 Hz). Mass spectrum: m/z: 162 [M]+. Found,
%: C 88.44; H 11.45. C12H18. Calculated, %: C 88.82;
H 11.18.
Dispiro[2.1.3.1]nonane (I). A mixture of 63 g of
bis-sulfonate VIII prepared as described above in the
synthesis of X, 55 g of anhydrous lithium bromide, and
300 ml of anhydrous acetone was heated for 7 h. The
precipitate was filtered off, and the filtrate was diluted
with 300 ml of water and extracted with diethyl ether.
The IR spectra were recorded on a UR-20 spec-
1
trometer from 3% solutions in CCl4. The H NMR
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 48 No. 4 2012
Molchanov
