Synthesis, growth and vibrational spectroscopic study of a novel coumarinoylthiazole

Article abstract of DOI:10.1016/j.saa.2012.07.123

An efficient route was developed for the synthesis of novel 3-(2-morpholinyl-4-phenylthiazol-5-oyl)coumarin (MPTC). FT-IR spectrum of MPTC was recorded and analyzed. The crystal structure data are also described. The vibrational wavenumbers were computed theoretically using the Gaussian03 package of programs using HF/6-31G(d) and B3LYP/6-31G(d) levels of theory. The data obtained from vibrational wave number calculations are used to assign vibrational bands observed in the infrared spectra of MPTC. The first hyperpolarizability, infrared absorption band intensities and intensities of raman active bands are reported. The calculated first hyperpolarizability is comparable with the values reported for compounds of similar structure. The structural parameters of MPTC obtained from XRD studies are in agreement with the calculated values. The unit cell parameters of crystals of MPTC are: a = 8.6017(10) A, b = 9.9735(5) A, c = 13.3870(13) A, α = 111.123(6)°, β = 90.102(9)°, γ = 110.246(6)°, and Z = 2,1.397 Mg/m³.

Full text of DOI:10.1016/j.saa.2012.07.123

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 1125–1132
Contents lists available at SciVerse ScienceDirect
Spectrochimica Acta Part A: Molecular and
Biomolecular Spectroscopy
journal homepage: www.elsevier.com/locate/saa
Synthesis, growth and vibrational spectroscopic study of a novel
coumarinoylthiazole
R. Reshmy a,c, D. Sajan b, K. Kurien Thomas a, A. Sulekha c, K.N. Rajasekharan d, S. Selvanayagam e,
Ö. Alver f,
⇑
a Department of Chemistry, Bishop Moore College, Mavelikara 690110, Alappuzha, Kerala, India
b Department of Physics, Bishop Moore College, Mavelikara 690110, Alappuzha, Kerala, India
c Department of Chemistry, S.N. College, Kollam 691001, Kerala, India
d Department of Chemistry, University of Kerala, Kariavattom Campus, Thiruvananthapuram, Kerala, India
e Department of Physics, Kalasalingam University, Krishnankoil 626126, Tamil Nadu, India
f Plant, Drug and Scientific Research Centre, Anadolu University, Eskißsehir, Turkey
g r a p h i c a l a b s t r a c t
h i g h l i g h t s
"
An efficient route was developed for
the synthesis of novel 3-(2-
morpholinyl-4-phenylthiazol-5-
oyl)coumarin (MPTC).
Vibrational spectra.
DFT analysis.
Molecular structure.
XRD analysis.
"
"
"
"
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 23 June 2012
Received in revised form 16 July 2012
Accepted 23 July 2012
Available online 4 August 2012
An efficient route was developed for the synthesis of novel 3-(2-morpholinyl-4-phenylthiazol-5-oyl)cou-
marin (MPTC). FT-IR spectrum of MPTC was recorded and analyzed. The crystal structure data are also
described. The vibrational wavenumbers were computed theoretically using the Gaussian03 package of
programs using HF/6-31G(d) and B3LYP/6-31G(d) levels of theory. The data obtained from vibrational
wave number calculations are used to assign vibrational bands observed in the infrared spectra of MPTC.
The first hyperpolarizability, infrared absorption band intensities and intensities of raman active bands are
reported. The calculated first hyperpolarizability is comparable with the values reported for compounds of
similar structure. The structural parameters of MPTC obtained from XRD studies are in agreement with the
calculated values. The unit cell parameters of crystals of MPTC are: a = 8.6017(10) Å, b = 9.9735(5) Å,
Keywords:
Coumarin
Thiazole
Crystal structure
FT-IR
c = 13.3870(13) Å,
a
= 111.123(6)°, b = 90.102(9)°,
c
= 110.246(6)°, and Z = 2,1.397 Mg/m3.
Ó 2012 Elsevier B.V. All rights reserved.
FT-Raman
Introduction
compounds [1]. The remarkable ability of heterocyclic nuclei to
serve both as biomimetics and as valuable pharmacophores has lar-
gely contributed to their unique value as key structural elements of
numerous drugs [2]. The varied biological activities of thiazoles and
coumarins have stimulated extensive research on their synthesis.
The reported bioactivities of these compounds include analgesic,
anaesthetic, antiallergic, anti-inflammatory, immunoregulatory,
Heterocyclic ring systems are a common structural motif in the
vast majority of pharmaceutically significant natural and synthetic
⇑
Corresponding author. Tel.: +90 222 335 05 80/3668.
E-mail address: ozguralver@anadolu.edu.tr (Ö. Alver).
1386-1425/$ - see front matter Ó 2012 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.saa.2012.07.123

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R. Reshmy et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 1125–1132
blood cholesterol lowering, anthelminitic, anti-tissuessive, antitu-
mour, antitubercular, antiarthiritic, immunosuppressive, psychoac-
tive, and several other activities [3,4], in addition to their technical
applications as fluorescent and solvatochromic dyes. Coumarins
serve as fluorogenic derivatization reagents for high-performance
liquid chromatographic analyses [5,6], fluorescence probes for
drug-protein binding studies [7] and fluorescence ionophores [8].
Warfarin, a coumarin derivative, is clinically prescribed drug, used
for the prophylaxis of thrombosis, embolism and certain cardiac
conditions [9]. Many coumarins bearing thiazole moieties are re-
ported to exhibit analgesic and anti-inflammatory activities [10–
13].
127.5, 128, 129, 129.5, 136.0, 152.5, 165.0, 169.0, 172.6, 173.0,
174.0, 180.0.
Crystal growth and X-ray structure determinations
Orange coloured, polygon shaped, crystals of the compound,
suitable for X-ray diffraction studies, were grown from a solution
of DMF by using a slow evaporation technique (Fig. 1). All mea-
surements were made on a Rigaku Mercury CCD X-ray diffractom-
eter by using graphite monochromated MoKR radiation
(k = 0.71070 A°). Single crystals of MPTC were mounted with
grease at the top of a glass fiber.
In the work reported herein, we have developed a convenient
synthetic access to 3-(2-morpholinyl-4-phenylthiazol-5-oyl)cou-
marin (MPTC) and have obtained crystals suitable for single crystal
X-ray diffraction studies. The MPTC crystal thus obtained was
found to belong to a triclinic crystal system with P-1 space group.
The atomic coordinates and equivalent isotropic displacement
parameters, bond lengths and bond angles, torsion angles were
measured. Detailed vibrational spectral studies, supported by den-
sity functional theory (DFT) calculations have been carried out to
elucidate the correlation between the molecular structure and
NLO property by investigating the intramolecular charge transfer
(ICT) interaction, the nature of the hydrogen bonds present and
the static first hyperpolarizability of MPTC.
Cell parameters were refined on observed reflections by using
the program CrystalClear (Rigaku MSC, Ver. 1.3, 2001). The col-
lected data were reduced by the program CrystalClear and an
absorption correction (multiscan) was applied. The reflection data
for MPTC were also corrected for Lorentz polarization effects. The
intensity data were collected at 150(2) K by the x/q-scan mode.
The cell refinement was done using the CrysAlis RED software
[16]. The structure was solved by direct methods with the program
SHELXS-97 and refined by full matrix least squares on F2 using
SHELXL-97 [17]. The graphical tool used was Diamond version
3.1f [18] and mercury [19]. Full crystallographic data (cif .le) relat-
ing to the crystal structure have been deposited with the Cam-
bridge Crystallographic Data Centre as CCDC 743681. All non-
hydrogen atoms in the molecule were refined anisotropically,
while some of the disordered atoms were refined isotropically.
The hydrogen atoms were placed at calculated positions. Summary
of the key crystallographic information are listed in Table 1.
X-ray data for MPTC was collected at room temperature on an
Experimental section
All chemicals from Aldrich and used without further purifica-
tion. Melting points were determined open capillary method using
an immersion bath of paraffin. Thin layer chromatography was
performed using silica gel-G (E. Merck, India) coated on glass plates
and the spots were visualised under UV-light. Synthesis was con-
ducted in a domestic microwave oven. NMR spectra were recorded
on a Brucker WM-400 (400 MHz) and JEOL GSX spectrometers, and
mass spectra were run on a JEOL GCMATE II GC-MS spectrometer.
FTIR spectra were measured on a Perkin-Elmer RXI spectrometer in
KBr matrix at a resolution of 2 cmꢀ1. The Raman spectra were re-
Enraf-Nonius diffractometer with CuKa radiation using x/2h scan
mode. The lattice parameters were determined from the least-
squares refinement of 25 well-centered reflections in the range
20° 6 h 6 30°. Two standard reflections for every 100 reflections
were periodically checked during data collection and they showed
no significant intensity variations. Cell refinement and data reduc-
tion were carried out using CAD-4 EXPRESS and XCAD4. The inten-
sities were corrected for Lorentz and polarization effects.
corded using
a Bruker RFS/100 NIR-FT Raman spectrometer
equipped with Ge diode detector and a Nd-YAG laser of 1064 nm
with an output of 150 mW was used as source of excitation. Spec-
tra were collected by 1000 repetitive scans over 30 min duration to
improve the signal-to-noise ratio. A correction according to the
fourth-power scattering factor was performed, but no correction
was made to the instrumental response. The upper limit for the Ra-
man shift is 3500 cmꢀ1 owing to detector sensitivity and the lower
Raman shift limit was around 50 cmꢀ1owing to the Rayleigh line
cutoff by the notch filter.
Computational details
Quantum chemical calculations have been performed at the
B3LYP/6-31G (d, p) to derive the optimized geometry and vibra-
tional wavenumbers of normal modes of MPTC (Fig. 2) using
Gaussian’03 program package [20]. Molecular geometries were
Synthesis of MPTC
3-Bromoacetylcoumarin [14] and N-benzoyl-N0,N0-diethylthiou-
rea [15] (1 mmol each) were dissolved in a minimum quantity of
dry acetone and microwave (180 W) irradiated for 30 s. The reac-
tion mixture was then poured into ice cold water, the pH was ad-
justed to 6 and the precipitate thus formed was filtered, dried and
recrystallized from ethanol–water (1:3) system.
Yield = 75%, MP = 118 °C, IR (K Br) cmꢀ1 = 3243, 2969,
2847,2156, 1720, 1665, 1602, 1581, 1523,1454, 1441, 1356,
1324, 1268,1241, 1222, 1148, 1114, 956, 875, 846,758, 710, 587;
1H NMR (400 MHz, DMSO-d6): d 3.61–3.63(t, 4H), 3.72–3.74(t,
4H), 6.99–7.03 (m, 3H, Ar–H), 7.19–7.29(m, 4H, Ar–H), 7.54–7.58
(m, J = 7.5 Hz, 2H), 7.99 (m, 1H); 13C NMR (125 MHz, DMSO-d6):
d 23.0, 25.0, 37.0, 49.0, 113.0, 122.8, 123.2, 124.8, 125.0, 127.0,
Fig. 1. Single crystal of the compound MPTC.

R. Reshmy et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 1125–1132
1127
Table 1
count for systematic errors caused by basis set incompleteness,
neglect of electron correlation and vibrational anharmonicity.
The vibrational modes were assigned on the basis of PED analysis
using VEDA 4 program [22] and its visualization interface. Normal
coordinate analysis of MPTC has been carried out to obtain a more
complete description of the molecular motions involved in the fun-
damentals. The Raman activities (Si) calculated by the Gaussian-03
program have been converted to relative Raman intensities (Ii)
using the following relationship derived from the basic theory of
Raman scattering [23–25].
Summary of crystal data and structure refinement for MCPT.
Empirical formula
Formula weight
Temperature
Wavelength
Crystal system
Space group
C23 H18 N2 O4
418.45
292(2) K
1.54180 Å
Triclinic
P1
S
Unit cell dimensions
a = 8.6017(10) Å;
b = 9.9753(5) Å; b = 90.102(9)°
a = 111.123(6)°
c = 13.3870(13) Å;
994.73(16) Å3
2
1.397 Mg/m3
1.731 mm-1
436
c = 110.246(6)°
Volume
Z
Density (calculated)
Absorption coefficient
F(000)
Crystal size
Theta range for data collection
Index ranges
Reflections collected
Independent reflections
Completeness to theta = 64.93°
Refinement method
Data / restraints / parameters
Goodness-of-fit on F2
Final R indices [I>2sigma(I)]
R indices (all data)
Extinction coefficient
Largest diff. peak and hole
4
fðmo
ꢀ
miÞ Si
Ii ¼
ð1Þ
i is
mi½1 ꢀ expðꢀhc Þꢁ
mi
kT
0.30 ꢂ 0.20 ꢂ 0.20 mm3
In the equation, m m
o is the exciting frequency (in cmꢀ1 units),
3.58–64.93°.
the vibrational wavenumber of the ith normal mode, h c and k are
universal constants, and f is the suitably chosen common scaling
factor for all the peak intensities.
0 6 h 6 10, ꢀ11 6 k 6 10, ꢀ15 6 l 6 15
3638
3301 [R(int) = 0.0670]
97.4%
Full-matrix least-squares on F2
3301/0/272
1.099
R1 = 4.6%, wR2 = 11.7%
R1 = 5.2%, wR2 = 12.2%
0.054(2)
0.289 and ꢀ0.255 e. Åꢀ3
Results and discussions
Synthesis of MPTC
The synthesis of MPTC was done using a microwave assisted
technique starting from 3-bromoacetylcoumarin [14] and N-ben-
zoyil-N,N0-morpholinylthiourea [15] (Scheme 1).
fully optimized by Berny’s optimization algorithm using redundant
internal co-ordinates and confirmed to be minimum energy con-
formations. The self-consistent field equation has been solved iter-
atively to reach the equilibrium geometry corresponding to the
saddle point on the potential energy surface (PES) and the analytic
second derivative of energy leads to the vibrational wave numbers.
The optimum geometry was determined by minimizing the energy
with respected to all geometrical parameters without imposing
molecular symmetry constraints.
Crystal growth and crystal structure determination
The lattice of MPTC crystals was determined to be triclinic in
nature with P1 symmetry. The crystal data and structural refine-
ment parameters are given above in Table 1. The ORTEP plot
(Fig. 3) of MPTC was drawn at 30% probability thermal displace-
ment ellipsoids with the atom numbering scheme. All the bond
lengths are normal and agree with the reported literature values.
The sum of the valence angle around N2 is 355.4° indicating no sig-
nificant pyramidalization of this nitrogen atom.
The calculated harmonic vibrational wave numbers were uni-
formly scaled down by using the scale factor 0.9613 [21], to ac-
Fig. 2. Structure of the molecule.

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R. Reshmy et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 1125–1132
O
O
O
S
O
O
O
N
Br
Dry Acetone
N
H
N
S
N
+
15 Sec.
MW
O
O
O
Scheme 1.
Fig. 3. ORTEP plot of molecule drawn at 30% probability level. Dashed line indicates CH. . .S intramolecular hydrogen bond.
The benzopyran ring is planar with a maximum deviation of
0
0.030(2) ÅA for atom C16 and its attached oxygen atom O3 deviates
0
0.033(3) ÅA from this plane. The fused benzene and pyran ring
makes a dihedral angle of 2.5(1)°. The thiazole and phenyl rings
0
are also coplanar, with a maximum0 deviation of 0.022(2) ÅA for
atom C2 in thiazole ring and 0.008(2) ÅA for atom C19 in phenyl ring.
The dihedral angles between benzopyran ring system with thiazole
and phenyl rings are 74.4(1) and 62.5(1)°, respectively; and that
between the thiazole ring and the phenyl ring is 33.5(1)°.
The morpholine ring adopts a chair conformation, as confirmed
0
0
by the puckering parameters q2 = 0.083(3) ÅA, q3 = ꢀ0.526(3) ÅA,
0
QT = 0.532(3) ÅA and h = 171.1(3)°. The atoms C4, C5, C6 and C7 of
the morpholine ring lie in a plane, whereas N2 and O1 deviate by
0
0.545(2) and ꢀ0.665(3) ÅA from this plane.
Interestingly, the crystalline structure is stabilized by intramo-
lecular C–H. . .S hydrogen bond involving atoms H7A and S1 (Fig. 3),
in addition to the van der Waals forces. The pattern of the hydro-
gen bonding and the packing of the molecules in the crystal are
shown in Fig. 4 and Fig. 5. In the observed structure, C–H. . .O
hydrogen bonds stabilize the packing of the molecules in the crys-
tal. Atom C17 at (x, y, z) interacts with O1 at (1ꢀx,ꢀy,1ꢀz) through
hydrogen atom H17, which forms a C–H. . .O hydrogen bond. This
hydrogen bond forms a dimer comprising R22(22) ring (Fig. 4). In
addition to this dimer, C5–H5B. . .O2 hydrogen bond links symme-
try related molecules with a symmetry position of (x, 1ꢀy, z), form-
ing a C(11) chain motif of C–H. . .O hydrogen bond in the unit cell.
This chain along with the dimers is shown in Fig. 5.
The comparison of the experimental bond parameters with the
theoretical data were presented in Table 2 followed by atomic
coordinates and equivalent isotropic displacement parameters in
Table 3. The C10–O3 bond length of 1.226(2) Å indicates the mole-
cule exists in the keto form in the solid-state [26]. The C19–N1 bond
length of 1.317(3) Å confirms its significant double-bond character.
The bond length between C7–O2 is 1.194(3) Å, a double bond and
C7–O1 is 1.382(3) Å a single bond indicates the presence of couma-
Fig. 4. Molecular packing viewed along ‘a’ axis, showing intermolecular C–H. . .O
hydrogen bonds as dashed lines forms a R22 (22) dimmers in the unit cell. For the
sake of clarity, H atoms not involved in hydrogen bonds have been omitted.
rin moiety. According to literature [27–31], the changes in bond
@
length in C O and C–N are consistent with the observation that
@
@
hydrogen bond decreases the double bond character of C O and
@
increases the double-bond characteristics of the C–N bond.
Vibrational spectral analysis
The normal mode analysis of MPTC is significantly more diffi-
cult due to large number of fundamental modes. The detailed

R. Reshmy et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 1125–1132
1129
Table 3
Atomic coordinates (ꢂ104) and equivalent isotropic displacement parameters
(A2 ꢂ 103) of MPTC molecule.U (eq) is defined as one third of the trace of the
orthogonalized Uij tensor.
Atoms
x
y
z
U (eq)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
ꢀ2120(3)
ꢀ3764(3)
ꢀ4513(3)
ꢀ3628(3)
ꢀ1952(2)
ꢀ1236(3)
1381(3)
612(3)
ꢀ941(2)
1527(3)
1845(2)
2041(2)
2100(2)
2774(3)
2864(3)
2310(3)
1671(3)
1566(3)
2369(3)
2615(3)
3635(4)
358(4)
ꢀ1350(3)
ꢀ1496(3)
ꢀ864(3)
ꢀ78(3)
98(2)
8967(2)
9036(2)
8505(2)
7908(2)
7828(2)
8357(2)
7680(2)
7092(2)
7195(2)
6237(2)
6157(2)
6862(2)
8049(2)
8677(2)
9794(2)
10292(2)
9679(2)
8567(2)
5363(2)
5090(2)
4446(3)
2999(2)
3541(2)
6405(1)
4707(1)
8292(1)
7701(2)
5530(1)
3317(2)
4864(1)
64(1)
72(1)
69(1)
55(1)
43(1)
49(1)
58(1)
45(1)
43(1)
48(1)
45(1)
44(1)
45(1)
52(1)
63(1)
70(1)
67(1)
55(1)
50(1)
66(1)
74(1)
78(1)
70(1)
51(1)
62(1)
61(1)
95(1)
69(1)
87(1)
52(1)
ꢀ566(2)
251(3)
892(2)
865(2)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(17)
C(18)
C(19)
C(20)
C(21)
C(22)
C(23)
N(1)
N(2)
O(1)
O(2)
O(3)
O(4)
S(1)
1328(2)
2804(2)
4284(2)
4854(2)
4289(2)
4897(3)
6080(3)
6670(3)
6068(3)
4730(2)
7081(3)
7920(3)
5696(3)
4688(3)
5350(2)
5518(2)
ꢀ468(2)
317(3)
Fig. 5. Molecular packing showing intermolecular C–H. . .O hydrogen bonds as
dashed lines forms a R22 (22) dimmers and C(11) chain in the unit cell. For the sake
of clarity, H atoms not involved in hydrogen bonds have been omitted.
vibrational assignments of fundamental modes along with the cal-
culated infrared and Raman intensities and normal modes descrip-
tion (characterized by PED) are reported in Table 4.
For visual comparison, the observed and simulated FT-IR and
FT-Raman spectra are presented in Figs. 6 and 7. The values ob-
tained from the calculated spectra were found to be close the
experimental values with reasonable accuracy. H-atoms involved
in intermolecular H- bonds show deviation in the simulated spec-
tra when compared with the experimental spectra. This deviation
is attributed to the fact that the theoretical spectrum was obtained
in gas phase without considering the inter molecular H-bonding
effects.
2348(4)
2298(2)
2663(3)
396(2)
2794(2)
1871(2)
3124(3)
2112(1)
328(2)
7098(2)
2793(1)
Table 2
Experimental and theoretical bond length, bond angle and torsion angles of MPTC (for the sake of clarity, H atoms are not involved).
Coordinatea
Calc.
Exp.
Coordinatea
Calc.
1.088
1.087
1.087
1.085
1.085
1.094
1.102
1.101
1.091
Exp.
0.930
0.930
0.930
0.930
0.930
0.970
0.970
0.970
0.970
Coordinatea
Calc.
Exp.
R(48,40)
R(40,36)
R(36,47)
R(47,22)
R(22,34)
R(22,21)
R(34,20)
R(21,19)
R(19,20)
R(20,23)
R(23,24)
R(24,26)
R(26,30)
R(19,17)
R(17,18)
R(17,12)
R(12,13)
R(13,16)
R(13,15)
R(15,3)
R(2,3)
R(1,2)
R(9,12)
R(4,9)
R(3,4)
R(5,6)
R(1,6)
R(1,7)
R(2,8)
R(5,10)
1.422
1.526
1.468
1.359
1.320
1.763
1.370
1.770
1.391
1.479
1.404
1.393
1.397
1.457
1.229
1.510
1.468
1.207
1.393
1.365
1.396
1.391
1.356
1.439
1.407
1.387
1.404
1.086
1.085
1.087
1.416
1.493
1.471
1.347
1.317
1.733
1.364
1.743
1.386
1.477
1.392
1.380
1.375
1.446
1.226
1.498
1.456
1.194
1.382
1.378
1.382
1.377
1.335
1.438
1.392
1.369
1.386
0.930
0.930
0.930
R(9,14)
R(30,33)
R(26,31)
R(24,27)
R(25,29)
R(40,H1)
R(40,H2)
R(36,H1)
R(36,H2)
R(37,H1)
R(37,H2)
R(35,H1)
A(12,13,16)
A(12,13,15)
A(12,9,4)
A(2,3,4)
A(2,1,6)
A(H1,40,H2)
A(H1,36,H2)
A(H1,37,H2)
A(H1,35,H2)
A(26,24,H)
126.07
116.18
121.29
121.37
120.77
108.73
108.37
108.76
108.18
120.50
119.99
120.03
118.67
120.03
54.21
126.10
116.95
120.87
121.90
120.60
107.80
108.40
107.90
108.10
119.70
119.90
119.60
119.60
119.70
54.5
1.094
1.102
1.101
1.094
0.970
0.970
0.970
0.970
A(23,25,H)
A(12,9,H)
A(4,9,H)
A(1,6,H)
R(35,H2)
A(37,48,40)
A(35,37,48)
A(35,47,36)
A(22,47,35)
A(21,22,34)
A(19,21,22)
A(22,34,20)
A(19,20,34)
A(24,23,20)
A(24,23,25)
A(26,30,28)
A(24,26,30)
A(17,19,20)
A(17,19,21)
A(18,17,19)
A(12,17,18)
A(9,12,13)
110.62
111.46
115.22
122.11
115.04
88.23
111.53
115.74
119.51
119.02
119.74
120.17
135.34
115.25
121.04
118.19
120.71
109.50
112.10
115.36
120.07
115.59
88.65
110.61
115.67
116.64
118.61
119.80
120.30
136.32
114.26
119.68
117.55
121.19
D(47,36,40,48)
D(47,35,37,48)
D(47,22,34,20)
D(20,34,22,21)
D(34,20,23,24)
D(20,23,24,26)
D(23,24,26,30)
D(34,20,19,17)
D(21,19,17,18)
D(20,19,17,18)
D(19,17,12,13)
D(17,12,13,15)
D(9,12,13,16)
D(9,4,3,2)
53.78
177.07
0.87
39.80
178.89
0.91
53.30
177.90
0.40
32.20
177.30
1.00
173.68
15.71
178.60
18.10
167.12
124.43
168.81
173.12
178.67
0.08
159.90
131.90
166.08
174.30
178.90
0.20
D(3,4,5,6)
D(1,2,3,15)
179.42
178.90
a
Coordinate descriptions are carried out by the numbers in Fig. 2 R, A, and D characters represent bond length (Å), angle (0) and dihedral angle (0) type of coordinates,
respectively.

1130
R. Reshmy et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 1125–1132
Table 4
Comparison of the experimental and calculated vibrational wavenumbers (cmꢀ1) of MPTC.
M.
aT.E.D.(P10%)
bExp.
Scaled waven.
B3LYP
mt
mb
Raman IR
ma
IIR
24.03
11.55
4.45
41.49
12.30
88.71
m134
m132
m131
m127
m125
m124
m120
m119
m118
m116
m114
m113
m109
m107
m100
t
t
t
t
t
t
t
t
t
t
t
t
33ꢀ30(44) +
32ꢀ28(45) +
t
t
29ꢀ25(21) +
t
32ꢀ28(20)
3067
3056 3050
3041 3040
3063
3207
3196
3191
3123
3113
3023
31ꢀ26(35)
3052
3047
2982
2973
2887
1749
1646
1621
1605
1564
1524
1474
1463
1356
1319
1296
1271
1211
1156
1143
1116
1107
1076
1028
993
932
916
841
791
767
751
729
714
700
651
647
603
585
565
505
448
10ꢀ5(56) +
43ꢀ37(55) +
39ꢀ35(94)
41ꢀ36(72) +
16ꢀ13(85)
18ꢀ17(89)
12ꢀ9(35)
t
11ꢀ6(18) +
t
t
14ꢀ9(18)
3020
2950
2936
3030 3035
2974 2971
2933 2961
2900 2875
1724 1738
1622 1613
1606 1604
1578 1591
1547 1549
1512 1508
1473 1475
1445 1467
1358 1355
1329 1313
1308 1294
1271 1274
1205 1209
1167 1162
1134 1135
1120 1116
1097 1102
1076 1074
1038 1035
45ꢀ50(40)
t
46ꢀ40(11)
1729
1831 461.25
1702 246.20
1592
1570
1676
1660
1617
70.14
3.97
46.58
26ꢀ24(20) +
t
28ꢀ25(19)
6ꢀ1(17) +
t
12ꢀ9(14) +
t
2ꢀ1(11)+
t
4ꢀ3(11)
47ꢀ22(27) +
t
34ꢀ22(15)
1513
1470
1445
1576 724.18
1524 181.09
6.31
76.06
1364 190.03
1340 160.60
d 41ꢀ36ꢀ42(22)
20ꢀ19(25)
d 12ꢀ9ꢀ14(25) +
34ꢀ20(9) + d 43ꢀ37ꢀ48(6) + d 45ꢀ40ꢀ48(6)
17ꢀ12(8) + 19ꢀ17(7) + d 2ꢀ1ꢀ7(5)
t
1513
1402
t
12ꢀ9(15) +
t
13ꢀ12(14) + d 14ꢀ9ꢀ4(11)
*
m95
t
1320
1306
*
m93
d 10ꢀ5ꢀ4(9) + d 6ꢀ5ꢀ10(8) +
t
t
m91
m86
m83
m81
m80
m78
m76
t
t
24ꢀ23(12)
5ꢀ4(20) +
1314
1252
1195
1182
36.56
15.01
42.13
38.40
t
15ꢀ3(16) + d 12ꢀ9ꢀ14(11)
30ꢀ26(11)d 30ꢀ26ꢀ31(10) + d 31ꢀ26ꢀ24(10)
1221
1156
d 33ꢀ30ꢀ28(16) + d 33ꢀ30ꢀ26(15) +
t
t
t
t
t
34ꢀ20(13)
6ꢀ5(15) +
t
2ꢀ1(12) + d 8ꢀ2ꢀ1(11)
1154 109.29
13ꢀ12(13)
1145
1113
1063
1027
964
40.32
8.67
28ꢀ25(18) +
t
26ꢀ24(16)
1083
1002
*
m74
d 48ꢀ37ꢀ35(6) + d 40ꢀ36ꢀ42(6)
13.40
52.25
11.91
15.02
15.35
m70
m65
m63
t
s
t
t
40ꢀ36(22) +
14ꢀ9ꢀ4ꢀ5(17) +
37ꢀ35(14)
t
37ꢀ35(17)
1003
937
910
856
800
778
760
731
710
692
660
640
609
577
559
501
436
409
989
934
915
840
795
767
752
729
712
701
656
649
609
590
571
509
451
409
s
17ꢀ12ꢀ9ꢀ14(17) +
s
13ꢀ12-9ꢀ14(11)
s
14ꢀ9ꢀ4ꢀ3(10)
911
855
947
870
*
m56
48ꢀ40(9) +
t
47ꢀ36(6)
16ꢀ13ꢀ12ꢀ17(10)
31ꢀ26ꢀ24ꢀ23(8) +
4ꢀ3(7) + 18ꢀ17ꢀ12ꢀ13(6) +
5ꢀ4ꢀ3ꢀ2(6) + 13ꢀ15-3ꢀ4(5) +
4ꢀ3(5) + 21ꢀ19(5)
33ꢀ30ꢀ28ꢀ25(6) + 33ꢀ30ꢀ26ꢀ24(6) +
m53
d 18ꢀ17ꢀ12(11) +
s
818 108.37
*
m52
s
t
s
t
s
s
32ꢀ28ꢀ25ꢀ23(7) +
s
28ꢀ30-26ꢀ31(6)
s
26ꢀ30ꢀ28ꢀ32(5) +
s
33ꢀ30ꢀ28ꢀ25(5)
793
777
754
738
724
673
669
624
605
584
522
463
423
5.74
18.28
17.23
10.61
38.33
31.72
6.90
35.96
19.92
15.43
4.86
*
m51
s
s
s
21ꢀ19ꢀ17ꢀ18(6)
s
20ꢀ19ꢀ17ꢀ12(6) + d 13ꢀ12ꢀ17(5)
762
708
662
612
*
m49
s
4ꢀ3ꢀ2ꢀ1(5)
*
m48
t
*
m46
s
t
13ꢀ12(5)
*
m43
d 20ꢀ34ꢀ22(6) + d 26ꢀ30ꢀ28(5)
m42
t
t
s
22ꢀ21(14)
*
m40
13ꢀ12(8) + -d 15ꢀ13ꢀ16(7) + d 6ꢀ5ꢀ(7)+d 3ꢀ2ꢀ1(6)
36ꢀ47ꢀ22ꢀ34(10)
m38
*
m37
d18ꢀ17ꢀ12(7)
d 37ꢀ48ꢀ40(9) +
d 15ꢀ13ꢀ12(6)
556
494
*
m34
t
21ꢀ19(6) + d 34ꢀ22ꢀ21(5)
*
m30
3.59
0.29
m28
s
30ꢀ26ꢀ24ꢀ23(18) +
s
30ꢀ28ꢀ25ꢀ23(18)
410
409
ma, Wavenumbers are scaled by SQM methodology.
m
m
b, Dual scaling factors were used, 0.955 above 1800 cmꢀ1, 0.967 under 1800 cmꢀ1 [20].
t, Unscaled wavenumbers.
IR, infrared.
IIR, Infrared intensities.
Waven, wavenumbers.
M, Mode.
Exp, Experimental.
m
, d, s, Stretching, bending and torsion, respectively.
a
Our vibrational wavenumbers assignments on the basis of total energy distribution (TED) calculations.
Our experimental IR wavenumbers.
b
*
T.E.D P 5.
3100–2800 cmꢀ1 spectral region
the coumarin ring. The calculated wave numbers of the above
mode is 3038 cmꢀ1 which is attributed to C–H stretching of the
coumarin ring attached to C5, C6 and C9 atoms. The vibrations aris-
ing from the pyranone ring is in the C–H stretching region.
The intense band at 3067 cmꢀ1 observed in Raman spectra is
attributed to the aromatic C–H stretching modes of the phenyl
ring. However, DFT predicts that the high intensity of this band
is reproduced mainly by the normal modes attributed to C–H
stretching of the phenyl rings attached to C30, C25 and C28 atoms.
The weak bands in IR at 3056 and 3041 cmꢀ1 are assigned to the
aromatic CꢀH stretching modes mode. The bands at 3030 cmꢀ1
in IR and 3028 cmꢀ1 in Raman are assigned to C–H stretching of
1750–1000 cmꢀ1 spectral region
Strong IR absorption bands at 1724 and 1729 cmꢀ1 in Raman
spectrum correspond to the carbonyl vibration in the pyranone
ring; the corresponding theoretical band with comparable inten-

R. Reshmy et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 1125–1132
1131
Fig. 6. (a) Theoretical IR and (b) Experimental IR of MPTC.
Fig. 8. Correlation diagram between the experimental and calculated vibrational
wavenumbers.
symmetric vibration the value of which is calculated as
1515 cmꢀ1. The medium intense bands in IR spectrum at 1380
and 1323 cmꢀ1 are predominantly C–C stretching bands of ben-
zene. The spectral distinction between CH2 groups involving C36
and C40 can be observed for bending vibrations. The scissoring
vibrations involving C36 and C40 can be observed in IR bands at
1473 and 1458 cmꢀ1 respectively. Other wagging vibrations are
mixed with the C–N in stretching vibrations of the thiazole ring
and CH2 twisting. The CH2 twisting modes involving C37 and C40
is observed as medium band in IR spectra at 1329 and medium
band in Raman spectra at 1326 cmꢀ1, which is coupled with the
C–N in stretching vibrations.The C–C stretching vibration at wave
numbers 1358 cmꢀ1 is coupled with the C–C–H bending modes,
which can be inferred from results of computations as well. The
medium bands at 1271 and 1248 cmꢀ1 in IR spectrum attributed
to ring stretching mode of coumarin ring.
Fig. 7. (a) Theoretical Raman and (b) Experimental Raman of MPTC.
sity is at 1760 cmꢀ1. In MPTC, the C O bond in the pyranone part is
@
@
@
@
conjugated with C3 C4 and C9 C12 double bonds. The increase in
@
@
single bond character due to conjugation lowers the wave number
of carbonyl and double bond absorptions. The orbital interaction
energy for n (LP1O4) ! rꢃ (C13–O15) is 156.0 kJ molꢀ1 and for n
(LP1 O15) ! pꢃ (C13–C12) is 66.74 kJ molꢀ1. In MPTC, the carbonyl
@
stretching (C17 O18) wave number has decreased from the com-
@
puted value of 1636 cmꢀ1, predicted by DFT, to the experimental
values at 1622 cmꢀ1 in IR spectrum. It is evident from the B3LYP
calculation that the band is downshifted by 14 cmꢀ1 for the pyra-
none carbonyl because of strong conjugation between the pyra-
none ring, thiazole ring and carbonyl group. The C–C ring
stretching vibrations have resulted in characteristic bands in both
the observed IR and Raman spectra, covering the spectral range
from 1610 to 1300 cmꢀ1. In MPTC, the ring mode manifests as
strong bands in Raman and infrared spectrum at 1592 and
1604 cmꢀ1 respectively, which are localized on the benzene part
of the molecule. These vibrations corresponds to the eg mode of
Below 1000 cmꢀ1 spectral region
The normal modes 10a, 11, 17a and 17b which allow C–H out-
of-plane bending vibrations are expected in the region 960–
780 cmꢀ1 [32–34]. The mode 10a is observed in the IR at
811 cmꢀ1 and in the Raman spectrum at 815 cmꢀ1 and is down-
shifted from the calculated wave number (832 cmꢀ1; 12% PED) as
a consequence of H-bonding interactions. The strong band ob-
served in the IR at 801 cmꢀ1 and the medium band at 838 cmꢀ1 Ra-
man spectrum is assigned to 11 modes. The radial skeletal (6a and
benzene at 1610 cmꢀ1
. The band in infrared spectrum at
1547 cmꢀ1 is attributed to C–C stretching. The medium intense
bands in Raman and infrared spectrum at 1578 and 1575 cmꢀ1
respectively, which are predominantly a C–C stretching of benzene.
The weak band at 1512 cmꢀ1 in the IR and a weak band at
1513 cmꢀ1 in the Raman spectrum are attributed to C N–C anti-
@
@

1132
R. Reshmy et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 1125–1132
[7] A. Takadate, T. Masuda, C. Tajima, M. Irikura, S. Goya, Analyt. Sci. 11 (1995) 97–
101.
[8] T. Masuda, C. Murata, A. Takadate, T. Tanaka, M. Irikura, S. Goya, Abstract of
papers, The 55th Symposium on Analytical Chemistry, Toyama, 1994, 251.
[9] A.M. Holbrook, J.A. Pereira, R. Labiris, Arch. Intern. Med. 165 (10) (2005) 1095–
1106.
[10] R.G. Kalkhambkar, G.M. Kulkarni, H. Shivkumar, R. Nagendra Rao, Eur. J. Med.
Chem. 42 (2007) 1272–1276.
[11] M.V. Kulkarni, V.D. Patil, S. Nanjappa, V.N. Biradar, Arch. Pharm. (Weinheim)
314 (314) (1981) 435–439.
[12] S.S. Hanmantgad, M.V. Kulkarni, V.D. Patil, Nat. Acad. Sci. Lett. (India) 7 (1984)
77–79.
[13] G.M. Kulkarni, M.V. Kulkarni, V.D. Patil, Rev. Roum. Chim. 35 (1990) 549–554.
[14] K.T. Vasudevan, M.V. Puttaraja, M.V. Kulkarni, Acta Cryst. C47 (1991) 775–777.
[15] K.K. Thomas, R. Reshmy, K.S. Ushadevi, J. Indian Chem. Soc. 84 (2007) 1016–
1019.
6b) and the out-of-plane skeletal (4,16a and 16b) vibrations are
listed in Table 4.
In general, B3LYP/6-31G(d) level of calculation with the dual
scaling factors and SQM methodology used in this study provided
reasonable agreement with the experimental findings. The correla-
tion values between the experimental and calculated vibrational
wave numbers are found to be 0.99980 ðmaÞ and 0.99978 ðmbÞ and
presented in Fig. 8. The results obtained in this study also indicate
that B3LYP/6-31G(d) method is reliable and it is helpful for the
understanding of vibrational spectrum and structural parameters
of MPTC.
[16] CrysAlis CCD and CrysAlis RED Versions 1.171.29.2 (CrysAlis 171. NET), Oxford
Diffraction Ltd., Abingdon, Oxfordshire, England, 2006.
Conclusions
[17] G.M. Sheldrick, Acta Crystallogr. A 64 (2008) 112–122.
[18] K. Brandenburg, Diamond Version 3.1f, Crystal Impact GbR, Bonn, Germany,
2008.
The synthesis, crystal structure data, and FT-IR spectrum of a
new coumarinoylthiazole viz. 3-(2-morpholinyl-4-phenylthiazol-
5-oyl)coumarin (MPTC) were reported. The molecular geometry
and wave numbers of MPTC were calculated using HF/6-31G(d)
and B3LYP/6-31G(d) basis. Optimized geometrical parameters of
MPTC are in agreement with the crystal structure data obtained
from XRD studies. The extended p-electron delocalization over
coumarin and phenyl moieties is responsible for the non-linearity
of the molecule. The Infrared intensities and Raman activities are
reported and the present study has shown that MPTC would be a
worthwhile subject for future studies of non-linear optics. The
compound is enantiomorphic polar. An interesting feature of the
crystal packing is the formation of a 1-fold symmetry axis with vir-
tually no symmetry and no mirrored planes.
[19] C.F. Macrae, P.R. Edgington, P. McCabe, E. Pidcock, G.P. Shields, R. Taylor, M.
Towler, J. van de Streek, J. Appl. Crystallogr. 39 (2006) 453–457.
[20] M. Frisch, G.W. Trucks, H.B. Schlegel, G.E. Scuseria, M.A. Robb, J.R. Cheeseman,
J.A. Montgomery, T. Vreven, K.N. Kudin, J.C. Burant, J.M. Millam, S.S. Iyengar, J.
Tomasi, V. Barone, B. Mennucci, M. Cossi, G. Scalmani, N. Rega, G.A. Petersson,
H. Nakatsuji, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T.
Nakajima, Y. Honda, O. Kitao, H. Nakai, M. Klene, X. Li, J.E. Knox, H.P. Hratchian,
J.B. Cross, C. Adamo, J. Jaramillo, R. Gomperts, R.E. Stratmann, O. Yazyev, A.J.
Austin, R. Cammi, C. Pomelli, J.W. Ochterski, P.Y. Ayala, K. Morokuma, G.A.
Voth, P. Salvador, J.J. Dannenberg, V.G. Zakrzewski, S. Dapprich, A.D. Daniels,
M.C. Strain, O. Farkas, D.K. Malick, A.D. Rabuck, K. Raghavachari, J.B. Foresman,
J.V. Ortiz, Q. Cui, A.G. Baboul, S. Clifford, J. Cioslowski, B.B. Stefanov, G. Liu, A.
Liashenko, P. Piskorz, I. Komaromi, R.L. Martin, D.J. Fox, T. Keith, M.A. Al-
Laham, C.Y. Peng, A. Nanayakkara, M. Challacombe, P.M.W. Gill, B. Johnson, W.
Chen, M.W. Wong, C. Gonzalez, J.A. Pople, Gaussian03, Revision C.02, Gaussian,
Inc., Wallingford, CT, 2004.
[21] J.B. Foresman, E. Frisch (Eds.), Exploring Chemistry with Electronic Structure
Methods: A Guide to Using Gaussian, Gaussian Inc., Pittsburg, PA, 1996.
[22] P. Flukiger, H.P. Luthi, S. Portmann, J. Weber, MOLEKEL 4.3, Swiss Center for
Scientific Computing, Manno, Switzerland, 2000.
Acknowledgement
[23] S. Portmann, H.P. Luthi, Chimia 54 (2000) 766–770.
We are thankful to the financial support provided by UGC, New
Delhi, India (F. No. 34-378/2008/SR).
[24] J.A. Faniran, H.F. Shurvell, Can. J. Chem. 46 (1968) 2089–2093.
[25] K. Balcı, S. Akyüz, Vib. Spectrosc. 48 (2008) 215–221.
[26] J. Baker, A.A. Jarzecki, P. Pulay, J. Phys. Chem. A 102 (1998) 1412–1424.
[27] R.C. Maurya, M.N. Jaiswal, R. Verma, B. Shukla, Synth. React. Inorg. Met.-Org.
Chem. 28 (1998) 1265–1281.
References
[28] E.D. Stevens, Acta Crystallogr. B 34 (1978) 544–551.
[1] V. Polshettiwar, R.S. Varma, Tetrahedron Lett. 48 (2007) 7343–7346.
[2] R.S. Varma, J. Heterocycl. Chem. 36 (1999) 1565–1571.
[3] R.O. Kennedy, R.D. Thornes, Coumarins: Biology, Applications and Mode of
Action, John Wiley & Sons, New York, 1997.
[29] T. Otterson, Acta Chim. Scand. A 29 (1975) 939–942.
[30] Q. Gao, G.A. Jeffrey, J.R. Ruble, R.K. McMullan, Acta Crystallogr. B 47 (1991)
742–747.
[31] J.L. Katz, B. Post, Acta Crystallogr. 13 (1960) 528–624.
[32] K.S. Thanthiriwatte, K.M.N. de Silva, J. Mol. Struct. 617 (2002) 169–174.
[33] C.L. Honeybourne, R.J. Ewen, K.J. Alkins, in: R.A. Hann, D. Bloor (Eds.), Inorganic
Materials for Non-linear Optics, Royal Society of Chemistry, Burlington House,
London, 1989.
[4] M.V. Kulkarni, G.M. Kulkarni, C.H. Lin, C.M. Sun, Curr. Med. Chem. 23 (2006)
2795–2818.
[5] A. Takadate, M. Irikura, T. Suehiro, H. Fujino, S. Goya, Chem. Pharm. Bull. 33
(1985) 1164–1169.
[6] A. Takadate, I. Yagashiro, M. Irikura, H. Fujino, S. Goya, Chem. Pharm. Bull. 37
(1989) 373–376.
[34] M.M. Bader, T. Hamada, A. Kakuta, J. Am. Chem. Soc. 114 (1992) 6475–6479.