R.N. Singh et al. / Journal of Molecular Structure 1061 (2014) 140–149
141
fluorescent materials (fluorescent dyes, light-emitting diodes
LEDs), fluorescent probes and fluorescent sensors), indicators
and spot test reagents as well as potential chemosensors [4].
structure, photoluminescence, multiple interaction, chemical reac-
tivity and first hyperpolarizability analysis of a newly synthesized
ethyl 2-cyano-3-{5-[(4-methylbenzenesulfonyl)-hydrazonomethyl]
-1H-pyrrol-2-yl}-acrylate.
(
Sulfur shows variable oxidation states. The insertion of a sulfo-
3
nyl group, ASO
2
A in organic compound incorporates a sp site, a
tetrahedral centre, providing a center for three dimensional struc-
tures. The sulfonyl group is bifunctional, a feature which permits
greater freedom in the design of compounds for specific applica-
tions and allows more flexibility for synthetically tailoring the
physical properties. Sulfonyl group has strong acceptor properties
compare to nitro and cyanovinyl groups. If both attached substitu-
2
. Experimental details
All the chemicals were used of analytical grade. Ethyl 2-cyano-3-
(
5-formyl-1H-pyrrol-2-yl)-acrylate (1) was prepared by an earlier
reported method [26]. 4-Methylbenzenesulfonylhydrazide was
prepared by stirring the equimolar reaction mixture of 4-meth-
ylbenzenesulfonylchloride and hydrazine hydrate in ethanol. The
Mass spectrum of (3) was recorded on JEOL-Acc TDF JMS-T100LC,
Accu TOF mass spectrometer. The H NMR spectrum of ECMHPA
6
was recorded in DMSO-d on Bruker DRX-300 spectrometer using
TMS as an internal reference. The FT-IR-spectrum of ECMHPA was
recorded in KBr medium on a Bruker-spectrometer. The spectrum
was recorded using 4 scan in the region 400–4000 cm at room
temperature, with scanning speed of 30 cm min
spectral resolution of 2.0 cm . The source and detector used in
the Bruker equipment were Hg-arc and DLaTGS respectively. The
2
ent in ASO A group are different, asymmetrical molecule result
and ultimately leading to variation in properties. The increased
transparency in the visible spectrum and synthetic flexibility make
sulfonyl compounds important for some applications. The chemis-
try of arylsulfonylhydrazones having sulfonamide and azomethine
group (C@NANHASO A) has been investigated owing to their
2
strong coordinating tendency, biological activity and inhibiting
1
ꢂ1
ꢂ1
capability. Tosylhydrazones (C@NANHATs) are versatile syn-
ꢂ1
and the
thetic intermediates for construction of the CAC
r
bonds by reduc-
ꢂ1
tive coupling with alkyl lithium reagents [5] and construction of
the sp –sp CAC bond, sp–sp3 CAC bond by a Pd catalyzed cou-
pling with terminal alkyne and aryl halide [6]. They are good syn-
thons for the synthesis of olefin derivatives [7–9] and various types
of heterocyclic compounds such as benzofurans, indoles [10].
These compounds have strong coordinating ability towards metal
2
3
ꢂ5
UV–Visible absorption spectrum of ECMHPA, (1 ꢃ 10 M in DMSO)
was recorded on ELICO SL-164 spectrophotometer. The emission
ꢂ5
spectrum of ECMHPA, (1 ꢃ 10 M in DMSO) was recorded on PL
Spectrometer LS-55, Perkin Elmer, UK
2
ions due to presence of a sulfonamide (ANHASO A) acidic,
replaceable proton [11,12]. In addition, hydrazide–hydrazones ex-
hibit photochromic [13], sensitive and selective analytical behavior
2
.1. Synthesis of ethyl 2-cyano-3-{5-[(4-methylbenzenesulfonyl)-
hydrazonomethyl]-1H-pyrrol-2–yl}-acrylate
[
[
14], corrosion inhibition [15] and non-linear optical properties
16–19].
The functionalized C-vinylpyrroles are prospective new materi-
A solution of 4-methylbenzenesulfonylhydrazide (0.2134 g,
.1464 mmol) in 15 ml methanol and 0.01 ml of conc. HCl as cata-
1
lyst was added drop-wise with stirring in solution of ethyl 2-cya-
no-3-(5-formyl-1H-pyrrol-2-yl)-acrylate (0.250 g, 1.1464 mmol)
in 10 ml methanol at room temperature. After stirring for 12 h,
the precipitate was obtained. The precipitate was filtered by vac-
uum filtration, washed with methanol and dried in air, afforded
als for molecular optical switches, nano-devices, photo- and elec-
tro-conducting applications and also used as ligands for new
photo catalysts, biologically active complexes [20–23].
2
The C@NANHASO A frame provides suitability for hyperpo-
larizability leading to NLO application. Arylsulfonylhydrazones
contain asymmetric transmitter backbone with donor–acceptor
types show high tendency to form non-centrosymmetric crystals
with large macroscopic quadratic nonlinearities are found to be
important for various NLO phenomena. Organic molecules having
better NLO properties have potential applications in areas such
as optical modulation, molecular switching, optical memory, and
frequency doubling [16–19]. The structure of the molecules can
be modified in numerous ways allowing to finely tuned NLO prop-
erties for desired applications.
(
0.200 g, 45.17%) of ECMHPA, as orange color solid. Anal. calcd.
for C18 S: C 55.94%, H 4.69%, N 14.50%, obs.: C 56.02%, H
4
H
18 4 4
N O
+
.72%, N 14.44%. MS (m/z): calcd. 386.1048, obs.: 387.21 [M +1].
3
. Quantum chemical calculations
All the quantum chemical calculations are carried out with
Gaussian 09 program package [27] using DFT level of theory,
B3LYP functional and 6-31G(d,p) as basis set. Global minima for
the reactants (1 and 2) and the product (3) were obtained by stud-
ies of the potential energy curves. H NMR chemical shifts, NBO
analysis, UV–Visible and vibrational wavenumbers were calculated
2
The sulfonyl azomethine (C@NANHASO A) frame provides
1
suitability for hydrogen bonding. Hydrogen bonds are of versatile
importance in fields of chemistry and biochemistry governings
chemical reactions, supramolecular structures, molecular assem-
blies and life processes. Intra and intermolecular hydrogen bonds
are classified in two categories depending upon the nature of
atoms involved in the hydrogen bridges. Quantum theory of atoms
in molecule (QTAIM) has been used to predict the strength and nat-
ure of hydrogen bonding interactions [24].
from optimized geometry of product (3).
4. Results and discussion
4.1. Molecular geometry
Density functional theory (DFT) adequately takes into account
electron correlation contributions, which are especially important
in systems containing extensive electron conjugation and/or elec-
tron lone pairs [25]. The B3LYP hybrid functional has shown to
successfully predict a wide range of molecular properties at a
relatively low computational cost.
In particular, the interest in synthesis of ethyl 2-cyano-3-{5-[(4-
methylbenzenesulfonyl)-hydrazonomethyl]-1H-pyrrol-2-yl}-acry-
late (ECMHPA) and evaluation of properties has been due to the
above mentioned properties and applications of hydrazones. In
present paper, we report the synthesis, spectroscopic, molecular
Optimized geometry of all the reactants (1, 2) and product (3, 4)
involved in chemical reaction is shown graphically in Scheme 1 of
Supplementary material. Selected optimized geometrical parame-
ters from dimer of ECMHPA, calculated at B3LYP/6-31G(d,p) are
1
listed in Table 1. The molecule possesses C symmetry. Tosylhyd-
razonomethyl group and Cyanovinyl pyrrole ring are twisted away
from each other by N20AC24AC34AN35 torsion angle of ꢂ5.6°.
The conformation of the NANASAO linkage is anti, with torsion
angles of 169.2°, which giving a folded appearance to the
molecules. The 4-methylphenyl ring is twisted away from any
eclipsing interaction with either SAO bond, with torsion angle