1062
Yields, boiling points, refractive indices, elemental analyses, and IR spectra of compounds V VII and IX XI
Found, % Calculated, %
SHABANOV et al.
Comp. Yield,
bp,
C
1
n2D0
Formula
IR spectrum (KBr), , cm
no.
%
(p, mm)
C
H
C
H
V
34.6
27.6
155 (2)
mp 31
162 (2)
61.08
6.28 C20H24O8
6.25 C20H24O8
61.22
61.22
6.12 1722 (C O); 1642 (C C);
1196, 1280, 1296 (C Oester)
6.12 1736 (C O); 1640, 1660
VI
1.4202 61.19
(C C); 1064, 1088, 1296
(C Oester
)
VII
IX
76.34
32.03
135 (2)
110 (1)
1.4632 59.08
1.4659 59.26
6.21 C18H22O8
5.93 C21H26O9
59.01
59.71
6.01 1702 (COOH), 1728 (C O),
1640 (C C)
6.16 3792, 3744, 3456 (OH); 1736
(C O); 1660, 1636 (C C);
1180, 1208, 1248, 1280
(C Oester
)
X
XI
11.2
26.2
125 (2)
163 (1.5) 1.4864 60.26
1.4778 60.23
6.43 C12H16O5
6.41 C24H32O10 60.0
60.0
6.66 1728 (C O), 1637 (C C)
6.66 1724 (C O), 1644 (C C)
cis,syn,cis-junction of the rings, respectively. The
isomeric products were separated by vacuum distilla-
tion in combination with column chromatography.
Their structure was established on the basis of the
IR spectra and chemical transformations, and the
molecular weight was determined by iodometric titra-
tion. The hydrolysis of macroheterocycles X and XI
gave cis-diacid III and diethylene glycol which were
identified by both chemical and spectral methods.
d = 10 mm) charged with aluminum oxide of activity
grade II (according to Brockman); a 1:2 (by volume)
chloroform hexane mixture was used as eluent.
[2+2]-Macrocyclization of cis-4-cyclohexene-1,2-
dicarboxylic acid (III) with 1,2-dibromoethane.
Diacid III, 8.5 g (0.05 mol), was dissolved in 150 ml
of 1-butanol, and the solution was neutralized with
5.6 g (0.1 mol) of powdered potassium hydroxide.
The released water was removed by azeotrope distilla-
tion, the solution was heated to the boiling point, and
9.4 g (0.05 mol) of 1,2-dibromoethane was added
with stirring over a period of 2 h. The mixture was
stirred for 20 h under reflux. When the reaction was
complete (TLC), the solvent was removed under
reduced pressure (25 mm), the residue was treated
with octane (5 50 ml), the extract was evaporated,
and the residue was distilled in a high vacuum. Two
fractions were thus obtained and were subjected to
to column chromatography on Al2O3 to isolate cis-
2,3 : 10,11-bis(1,2,3,6-tetrahydrobenzo)-1,4,9,12-tetra-
oxo-5,8,13,16-tetraoxa-syn-cyclohexadecane (V) and
cis-2,3 : 10,11-bis(1,2,3,6-tetrahydrobenzo)-1,4,9,12-
tetraoxo-5,8,13,16-tetraoxa-anti-cyclohexadecane (VI)
(see table).
Taking into account that compound XI shows in
the IR spectrum only one absorption band from the
1
double bonds ( C C 1644 cm ), cis,syn,cis-junction
of the cyclohexene and polyester rings therein may be
assumed.
EXPERIMENTAL
The IR spectra were recorded on Beckmann and
UR-20 spectrometers from samples pelleted with KBr.
The mass spectra (70 eV) of compounds V and VI
were recorded on an MKh-1310 spectrometer, batch
inlet temperature 235 C. The progress of reactions
and the purity of products were monitored by TLC on
Silufol plates. Mono- and dipotassium salts of cis-4-
cyclohexene-1,2-dicarboxylic acid were obtained by
potentiometric titration in 1-butanol using glass and
silver chloride electrodes; the pH was measured with
the aid of a pH-340 instrument. Standard solutions of
iodine (0.01 M) and sodium thiosulfate (0.005 M)
were used in the iodometric titration of compounds
V, VI, and IX XI. Stereoisomers V and VI were
separated by vacuum distillation followed by column
chromatography using a glass column (h = 100 mm,
1,2-Bis(2-carboxy-1,2,3,6-tetrahydrobenzoyloxy)-
ethane (VII) was synthesized in a similar way from
8.5 g (0.05 mol) of diacid III, 2.8 g (0.05 mol) of
powdered potassium hydroxide, and 4.7 g (0.025 mol)
of 1,2-dibromoethane. The properties of product VII
are given in table.
Following the above procedure, from 18.3 g
(0.05 mol) of compound VII and 9.4 g (0.05 mol) of
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 7 2002
Shabanov
