ISSN 1070-4272, Russian Journal of Applied Chemistry, 2008, Vol. 81, No. 9, pp. 1602!1607. + Pleiades Publishing, Ltd., 2008.
Original Russian Text + N.S. Novikova, E.D. Kilimenchuk, M.Yu. Yarkova, S.B. Meshkova, Z.M. Topilova, 2008, published in Zhurnal Prikladnoi
Khimii, 2008, Vol. 81, No. 9, pp. 1528!1532.
AND INDUSTRIAL ORGANIC CHEMISTRY
Synthesis and Mesomorphism
of 1,3-Benzenedicarboxylic Acid Derivatives
N. S. Novikova, E. D. Kilimenchuk, M. Yu. Yarkova, S. B. Meshkova, and Z. M. Topilova
Bogatskii Physicochemical Institute, National Academy of Sciences of Ukraine, Odessa, Ukraine
Received November 26, 2007
Abstract-4-Methoxy-1,3-benzenedicarboxylic acid esters and 4-(4-hexyloxybenzoylamino)phenyl 1,3-ben-
zenedicarboxylate, each containing five aromatic rings, were synthesized. The influence of the structure
of the synthesized banana-like compounds on their mesogenic activity was examined.
Much attention in chemistry of liquid crystals is
given to synthesis of molecules having a bent shape,
so-called banana-like molecules . Such compounds
can form a mesophase with ferroelectric properties
and find use as components for liquid crystal dis-
plays, increasing their speed. Therefore, revealing
a correlation between their structure and meso-
morphic properties is a topical problem.
The central fragment of banana-like compounds
is most frequently 1,3-disubstituted benzene contain-
ing the same or different functional groups. The
side fragments include four to six aromatic or het-
eroaromatic rings linked by bridging groups (ester,
azomethine, azoxy, double, or triple bond). Data on
preparation of liquid crystal banana-like compounds
with the amide linking group are lacking, whereas
rodlike mesomorphic aromatic acid amides forming
nematic and smectic phases have been reported .
There are data on rodlike and discotic liquid crystals
forming complexes with lanthanides, e.g., on substi-
tuted Schiff bases [3, 4], b-aminovinyl ketones [5, 6],
substituted diaza-18-crown-6 ethers ; some of such
complexes exhibit luminescence properties. Com-
plexes of lanthanides with banana-like liquid crystals
have not been studied. The banana-like esters of
1,3-benzenedicarboxylic and 4-bromo-1,3-benzenedi-
carboxylic acids, described in the literature , have
the structure that does not allow any complexing
activity to be expected.
The goal of this study was to prepare 1,3-ben-
zenedicarboxylic acid esters containing an amide
group as the second linking fragment and 4-meth-
oxy-1,3-benzenedicarboxylic acid esters, to examine
their mesomorphism, and to evaluate their complex-
ing power toward lanthanides.
1,3-Benzendicarboxylic and 4-methoxy-1,3-ben-
zenedicarboxylic acid derivatives were prepared by
the scheme shown below.
Chlorides of 1,3-benzenedicarboxylic and alkoxy-
benzoic acids were prepared by the standard proce-
dure  in thionyl chloride in the presence of DMF.
N-(4-Hydroxyphenyl)-4-hexyloxybenzamide I was
prepared by the modified procedure from . Its
structure was proved by mass spectrometry and IR
= 1680 cm
yloxybenzoylamino)phenoxycarbonyl]benzene II was
prepared in absolute acetone in the presence of tri-
ethylamine from isophthaloyl chloride and approp-
riate phenol I. Compound II shows no mesomorphic
properties, has high melting point, and is very diffi-
cultly soluble in the majority of solvents.
Thus, introduction of an amide group as linker
into side fragments of bent molecules negatively
affects all the characteristics, including the meso-
genic power. Therefore, we prepared 4-methoxy-1,3-
benzenedicarboxylic acid derivatives containing
exclusively ester groups in side fragments.
The starting 4-alkoxyphenols III were prepared
by the procedure given in . 4-(4-Alkoxyphenoxy-
carbonyl)phenols IV were prepared by esterification
in the presence of sulfuric acid in anhydrous benzene
. The structures of phenols IV were confirmed by
IR spectroscopy and mass spectrometry (Table 1).
phenylene]benzenes VIII were prepared from the