Solvent-free synthesis, spectral correlations and antimicrobial activities of some aryl e 2-propen-1-ones

Article abstract of DOI:10.1016/j.saa.2013.04.048

Totally 38 aryl E 2-propen-1-ones including nine substituted styryl 4-iodophenyl ketones have been synthesised using solvent-free SiO ₂-H₃PO₄ catalyzed Aldol condensation between respective methyl ketones and substituted benzaldehydes under microwave irradiation. The yields of the ketones are more than 80%. The synthesised chalcones were characterized by their analytical, physical and spectroscopic data. The spectral frequencies of synthesised substituted styryl 4-iodophenyl ketones have been correlated with Hammett substituent constants, F and R parameters using single and multi-linear regression analysis. The antimicrobial activities of 4-iodophenyl chalcones have been studied using Bauer-Kirby method.

Full text of DOI:10.1016/j.saa.2013.04.048

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
Contents lists available at SciVerse ScienceDirect
Spectrochimica Acta Part A: Molecular and
Biomolecular Spectroscopy
journal homepage: www.elsevier.com/locate/saa
Solvent-free synthesis, spectral correlations and antimicrobial activities
of some aryl E 2-propen-1-ones
K. Sathiyamoorthi a, V. Mala a, S.P. Sakthinathan a, D. Kamalakkannan a, R. Suresh a,
G. Vanangamudi a, , G. Thirunarayanan b
⇑
a PG & Research Department of Chemistry, Government Arts College, C-Mutlur, Chidambaram 608 102, India
b Department of Chemistry, Annamalai University, Annamalainagar 608 002, India
h i g h l i g h t s
g r a p h i c a l a b s t r a c t
ꢀ
Green aldol condensation gives more
than 85% yield of a series of E 2-
propen-1-ones.
ꢀ
These aryl E 2-propen-1-ones were
characterized by their analytical and
spectral data.
ꢀ
ꢀ
Hammett spectral linearity has been
studied for 40-iodophenyl chalcones.
Antimicrobial activities of 40-
iodophenyl chalcones have also been
studied.
a r t i c l e i n f o
a b s t r a c t
Article history:
Totally 38 aryl E 2-propen-1-ones including nine substituted styryl 4-iodophenyl ketones have been syn-
thesised using solvent-free SiO2–H3PO4 catalyzed Aldol condensation between respective methyl ketones
and substituted benzaldehydes under microwave irradiation. The yields of the ketones are more than
80%. The synthesised chalcones were characterized by their analytical, physical and spectroscopic data.
The spectral frequencies of synthesised substituted styryl 4-iodophenyl ketones have been correlated
with Hammett substituent constants, F and R parameters using single and multi-linear regression anal-
ysis. The antimicrobial activities of 4-iodophenyl chalcones have been studied using Bauer–Kirby
method.
Received 10 November 2012
Received in revised form 8 April 2013
Accepted 10 April 2013
Available online 19 April 2013
Keywords:
Solvent-free synthesis
Styryl 4-iodophenyl ketones
SiO2–H3PO4 catalyst
Aldol condensation
IR and NMR spectra
Antimicrobial activities
Ó 2013 Elsevier B.V. All rights reserved.
Introduction
and acyl compounds. Thermal condensation reactions have been
found to be sluggish and time-consuming with poor yields. However
Numerous greener solvent-free [1,2] synthetic methods avail-
able for synthesis of organics. These solvent free reactions involving
the formation of carbon-carbon bond and carbon-heteroatom bond
are important and interesting in green synthesis. Based on this the
Aldol [3], Crossed-Aldol [4], Knoevenagel [5], Mannich [6], Michael
[7] and Wittig [8] reactions have been applied for synthesising iso-
meric biologically active compounds such as chalcones, alkenes
in microwave conditions, the reaction is faster, giving appreciable
yield involving easier process of isolation of the products. Scientists
and Chemists have used microwave irradiation technique for solid
phase green synthesis [8,9]. Numerous green catalysts such as fly-
ash:sulphuric acid [1], silica-sulphuric acid [10,11] anhydrous zinc
chloride [12], ground chemistry catalysts-grinding the reactants
with sodium hydroxide [13], aqueous alkali in lower temperature
[14], solid sulphonic acid from bamboo [15], barium hydroxide [16],
anhydrous sodium bicarbonate [17], microwave assisted synthesis
[18], Fly-ash:water [19], triphenylphosphite [20], alkali earth metals
⇑
Corresponding author. Tel.: +91 4144 230730.
E-mail address: drgvsibi@gmail.com (G. Vanangamudi).
1386-1425/$ - see front matter Ó 2013 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.saa.2013.04.048

246
K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
[21], KF/Al2O3 [22] and sulfated titania [23] and silicotungstic acid [24]
have been reported for the synthesis of many number of organic com-
pounds. Chalcones possess various multipronged activities such as
antimicrobial [25], antidepressants [26], antiplosmodial [27], anti-aids
[28] and insect antifeedant activities [29]. Spectral data is useful for
prediction of ground state equilibration of organic molecules such as
s-cis and s-trans isomers of alkenes, alkynes, benzoyl chlorides, sty-
recording NMR spectra, operating at 400 MHz has been utilized for
recording 1H spectra and 100 MHz for 13C spectra in CDCl3 solvent
using TMS as internal standard. Mass spectra were recorded on a
SIMADZU GC-MS2010 Spectrometer using Electron Impact (EI)
techniques.
Preparation of SiO2–H3PO4 catalyst
renes and a, b-unsaturated ketones [27,29]. The Quantitative structure
activity relationship and quantitative structure property relationships
were used for finding the structure of molecule, quantitative and qual-
itative analysis [27–29]. Their use in structure parameter correlations
becomes popular for studying biological activities[30], normal co-ordi-
nate analysis [31] and transition states of reaction mechanisms [32].
Infrared spectroscopy is a powerful tool technique for the qualitative
and quantitative study of natural and synthetic molecules [33]. IRspec-
troscopy can provide information about the nature, concentration and
structure of samples at the molecular level [34]. A great deal of work
In a 50 mL Borosil beaker, 2 g of silica (10–20l) and 2 mL of
ortho phosphoric acid were taken and mixed thoroughly with glass
rod. This mixture was heated on a hot air oven at 85 °C for 1 h,
cooled to room temperature, stored in a borosil bottle and tightly
capped. This was characterized by infrared spectra and SEM
analysis.
Infrared spectral data of SiO2–H3PO4 are m
(cmꢁ1): 3437(PAOH);
2932, 2849 (PAOAH); 1747, (O@PAOH); 1091(P@O), 800(PAO);
464[50].
has been devoted to the reactivity of a,b-carbonyl compounds particu-
The SEM images of pure SiO2 and SiO2–H3PO4 at two different
magnifications are shown in Fig. 1a–d. Fig. 1a and b depicted that
the crystallinity is found to be more in SiO2. The spherical shaped
particles are clearly seen at both magnifications in Fig. 1a and b.
Fig. 1a reveals that the globular structure of pure silica (round
shaped particle). This also seen from Fig. 1c and d that some of
the particles are slightly corroded by H3PO4 (indicated by arrow
mark) and this may be due to dissolution of SiO2by H3PO4. This will
further confirmed by Fig. 1d, the well-shaped particles of pure SiO2.
Fig. 1b is aggregated to Fig. 1d due to presence of H3PO4.
larly, the theoretical study of substituent effects has been studied on
long range interactions in the b-sheet structure [35] of oligopeptides,
enone–dienol tautomerism [36]. Literature study reveals QSAR study
of substituted benzo[a] phenazines [37], cancer agents, Diels-Alder
reactions [38], density functional theory [39], gas phase reactivity of al-
kylallylsulphides[40] and rotational barriers in selenomides [41]. San-
telli et.al. [42] have studied the quantitative structural relationships in
a, b-unsaturated carbonyl compounds between the half wave reduc-
tion potential, the frontier orbital energy and the Hammett p values.
r
Dhami and Stothers [43] have extensively studied the 1H nmr spectra
of a large number of acetophenones and styrenes with a view to estab-
lish the validity of the additivity of substituent effect in aromatic
shielding first observed by Laturber [44]. Savin and co-workers [45]
have studied the NMR data of unsaturated ketones of the type RC6H4-
ACH@CHACOCH3 and sought Hammett correlations for the ethylenic
protons. Solcaniova [46] and co-workers have measured 1H and 13C
NMR spectra of substituted styrenes, styryl phenyls and they obtained
good Hammett correlations for the olefinic protons and carbons. At
present, scientists [2,3,5,9,12,27] have paid more interest to correlate
the group frequencies of spectral data with Hammett substituent con-
stants to explain the substituent effects of organic compounds. Re-
cently Thirunarayanan co-workers [2a,3,4,9,12,47–49] investigated
elaborately the single and multi-regression analysis of substituent ef-
fects on alpha and beta hydrogen and carbons of some pyrrolyl, naph-
thyl and furyl chalcones. However there is no information available in
the literature for the synthesis of chalcones using green catalyst SiO2–
H3PO4 by crossed-aldol condensation, correlation study of infrared and
NMR spectroscopic data with Hammett equation and antimicrobial
activities in the past with substituted styryl 4-iodo phenyl ketones.
Therefore the authors have taken efforts to synthesized some substi-
tuted styryl 4-iodophenyl ketones by condensation of 4-iodoaceto-
phenone with various substituted benzaldehydes, studied the
quantitative structure property relationship from the group fre-
quencies and studied their antimicrobial activities.
General procedure for synthesis of substituted styryl4-
iodophenylketones
An appropriate mixture of 4-iodoacetophenone (2 mmol) and
substituted benzaldehydes (2 mmol) and SiO2–H3PO4(0.5 g) taken
in 50 mL corning glass tube and tightly capped. The reaction mixture
was subjected to microwave irradiation at 460W for 8–10 min in a
microwave oven (Scheme 1) (LG Grill, Intellowave, MicrowaveOven,
160–800 W) and then cooled to room temperature. Added 10 mL of
dichloromethane, the organic layer has been separated by filtration
and on evaporation yields the solid product. The solid, on recrystal-
lization with benzene-hexane mixture (1:1) afforded glittering pale
yellow solid. About 10 mL of dichlorometh-ane was added, the or-
ganic layer was removed by filtration and the catalyst was recovered
as solid. The catalyst was washed with ethyl acetate (10 mL) and
heated at 110 °C, then it was reused for further runs.
Results and discussion
In our organic chemistry research laboratory, we attempts to
synthesize aryl chalcone derivatives by crossed-aldol condensation
of electron withdrawing as well as electron donating group substi-
tuted acetophenone and benzaldehydes in the presence of vigorous
acidic catalyst SiO2–H3PO4 in microwave irradiation. Hence the
authors have synthesized the chalcone derivatives by the reaction
between 2 mmol of aryl iodo ketones, 2 mmol substituted benzalde-
hydes in microwave irradiation with 0.5 g of SiO2–H3PO4 catalyst
(Scheme 1). During the course of this reaction SiO2–H3PO4 catalyses
aldol-condensation between aryl ketone and aldehydes and elimi-
nation of water gave the chalcones. The yields of the chalcones in
this reaction are more than 85%. The proposed general mechanism
of this reaction is given in Fig. 2. Further we have investigated this
reaction with equimolar quantities of the 4-iodoacetophenone and
benzaldehyde. In this reaction the obtained yield was 87%. The effect
of catalyst in this reaction was studied by varying the catalyst quan-
tity from 0.1 g to 1 g. As the catalyst quantity is increased from 0.1 g
to 1 g, the percentage of yield of product is increased from 85% to
Experimental
General
All chemicals used were purchased from Sigma–Aldrich and E-
Merck chemical companies. Melting points of all chalcones were
determined in open glass capillaries on SUNTEX melting point
apparatus and are uncorrected. The UV spectra of all synthesized
chalcones were recorded in ELICO-BL222 SPECTROMETER (kmax
nm) in spectral grade methanol. Infrared spectra (KBr, 4000–
400 cmꢁ1) were recorded on AVATAR-300 Fourier transform spec-
trophotometer. Bruker AV400 NMR spectrometer has been used for

K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
247
Fig. 1. SEM images of pure SiO2 and H3PO4: (a) Pure SiO2 (5
lm); (b) pure SiO2 (20
l
m); (c) SiO2–H3PO4 (5
lm) (
– corroded); (d) SiO2–H3PO4 (20
lm) (
– corroded).
O
O
H
O
CH3
H
SiO2-H3PO4
MW, 460W
H
I
I
X
X
(30-38)
X= H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4- OCH3, 4-CH3
Scheme 1. Synthesis of substituted styryl 4-iodophenyl chalcones.
87%. Further increase the catalyst amount there is no significant
increasingof thepercentage of product. This catalyticeffect is shown
in (Fig. 3). The optimum quantity of catalyst loading was found to be
0.4 g. We have carried out this reaction with various substituted ke-
tones and benzaldehydes. The results, analytical and mass spectral
data are summarized in Table 1. There is no significant effect of sub-
stituents on the condensation reaction. The reusability of this cata-
lyst was studied the aldol reaction of 4-iodoacetophenone with
benzaldehyde and is presented in Table 2. From Table 2, first two
runs gave 87% product. The third, fourth and fifth runs of reactions
gave the yields 86.5%, 86.5% and 86% of chalcones. There was no
appreciable loss in its effect of catalytic activity was observed up
to fifth run. The complete spectroscopic data of selective compounds
(entries 30–38) are summarized below.
144.00(Cb), 189.44(CO), 137.28(C1), 132.31(C2, C6), 138.03(C3, C5),
100.20(C4), 133.62ðC0 Þ, 129.89ðC0 ; C0 Þ, 129.93ðC0 ; C0 Þ, 121.90ðC0 Þ.
1
2
6
3
5
4
(E)-1-(4-iodophenyl)-3-(4-chlorophenyl)prop-2-en-1-one(32):
IR(KBr, cm1)
831.32(CHop), 1056.99(CH@CHop), 536.21(C@Cop); 1H NMR(400MHz,
CDCl3, ppm) d = 7.579(1H, , d), 7.879(1H, b,d), 7.264–7.787(8H, m,
Ar-H); 13C NMR(CDCl3, ppm); d = 121.81(C
), 143.95(Cb),
m = 1666.50(COs-cis), 1598.31(COs-trans), 1105.21(CHip),
a
a
189.25(CO); 138.02(C1), 129.35(C2,C6), 129.70(C3,C5), 100.48(C4),
133.19ðC01Þ, 127.44ðC20 ; C60 Þ, 138.02ðC03; C50 Þ, 129.93ðC04Þ.
(E)-1-(4-iodophenyl)-3-(2-fluorophenyl)prop-2-en-1-one(33):
IR(KBr, cmꢁ1
)
m
= 1660.71(COs-cis), 1602.90(COs-trans), 1095.60
(CHip), 813.96(CHop), 1002.98(CH@CHop), 511.14(C@Cop); 1H
NMR(400 MHz, CDCl3, ppm) d = 7.745(1H, , d), 7.883(1H, b, d),
7.127–7.928(8H, m, Ar-H); 13C NMR(100 MHz, CDCl3, ppm)
a
(E)-1-(4-iodophenyl)-3-phenylprop-2-en-1-one(30): IR (KBr, cmꢁ1
= 1627.92(COs-cis), 1597.10(COs-trans), 1122.57(CHip), 756.10(CHop),
1002.98(CH@CHop), 551.64(C@Cop); 1H NMR(400 MHz, CDCl3,
)
d = 122.68(Ca), 138.00(Cb), 189.61(CO), 137.20(C1), 132.09(C2),
m
137.95(C3), 100.85(C4), 138.00(C5), 132.18(C6), 123.84ðC01Þ,
160.46ðC02Þ, 116.21ðC30 Þ, 129.77ðC40 Þ, 124.58ðC50 Þ, 129.80ðC06Þ.
(E)-1-(4-iodophenyl)-3-(4-fluorophenyl)prop-2-en-1-one(34):
ppm): d = 7.740(1H,
a, d), 7.877(1H, b, d), 7.263–7.867(9H, m, Ar-
H); 13C NMR(100 MHz CDCl3, ppm): d = 121.48(C ), 145.47(Cb),
IR(KBr, cmꢁ1
)
m
= 1654.92(COs-cis), 1593.20(COs-trans), 1103.31
a
189.75(CO), 137.50(C1), 129.96(C2, C6), 144.03(C3, C5), 100.63(C4),
(CHip), 823.60(CHop), 987.55(CH@CHop), 514.99(C@Cop), 1H
134.60ðC01Þ, 128.55ðC20 ; C60 Þ, 130.81ðC03; C50 Þ, 121.48ðC04Þ.
NMR(400 MHz CDCl3, ppm) d = 7.393(1H, a, d), 7.78(1H, b, d),
(E)-1-(4-iodophenyl)-3-(4-bromophenyl)prop-2-en-one(31):
IR
7.096–7.801(8H, m, Ar-H); 13C NMR(100 MHz, CDCl3, ppm)
(KBr, cmꢁ1
798.53(CHop), 1010.70(CH@CHop), 543.93(C@Cop); 1H NMR(400 MHz,
CDCl3, ppm): d = 7.564(1H, , d), 7.878(1H, b, d), 7.264–7.768(8H
m, Ar-H); 13C NMR(100MHz, CDCl3, ppm): d = 121.90(C ),
)
m
= 1654.72(COs-cis), 1604.77(COs-trans), 1103.28(CHip),
d = 121.14(C ), 144.13(Cb),189.50(CO), 137.39(C1), 130.99(C2,C6),
a
137.99(C3,C5), 100.75(C4), 130.95 ðC0 Þ, 129.92 ðC0 ; C0 Þ, 116.24
1
2
6
a
ðC03; C05Þ, 162.96 ðC04Þ.
a

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K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
PA
S
SPA
O
O
O
O
O
CH3
CH2
H
SPA
MW, 460W
I
I
I
X
X
O
PA
CH3
S
O
O
O
OH
I
I
X
I
X
O
H
H
I
X
(entry 30; X=H)
Fig. 2. Synthesis of substituted styryl 4-iodophenyl ketones by silica-phosphoric acid catalyzed aldol condensation.
ppm) d = 120.81(Ca), 141.09(Cb), 190.41(CO), 137.86(C1), 132.04
(C2), 139.74(C3, C5), 100.32(C4), 111.28(C01; C30 ), 158.90(C20 ),
122.31(C05), 129.40(C40 ), 130.03(C06).
(E)-1-(4-iodophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one(37):
IR(KBr, cmꢁ1
)
m
= 1640.37(COs-cis), 1593.22(COs-trans), 1134.10
(CHip), 812.03(CHop), 1006.84(CH@CHop), 524.64(C@Cop); 1H NMR
(400 MHz, CDCl3, ppm) d = 7.425(1H, , d), 7.799(1H, b, d), 7.224–
7.815(8H, m, Ar-H), 3.864(3H, s,-OCH3); 13C NMR(100 MHz, CDCl3,
a
ppm) d = 120.45(C ), 145.59(Cb), 189.33(CO), 137.65(C1), 129.94
a
(C2, C6), 131.98(C3, C5), 100.48(C4), 128.60(C0 ), 128.60(C0 ; C0 ),
1
2
6
137.88(C03; C50 ), 145.59(C04).
(E)-1-(4-iodophenyl)-3-tolylphenyl–prop-2-en-1-one(38): IR(KBr,
(cmꢁ1
= 1653(COs-cis), 1591.30(COs-trans), 1114.90(CHip),
815.89(CHop), 1018.41(CH@CHop), 530.42(C@Cop); 1H NMR
)
m
(400 MHz CDCl3, ppm) d = 6.943(1H a, d), 7.604(1H, b, d), 2.401(s,
3H, CH3,); 13C NMR(100 MHz CDCl3, ppm) d = 119.12(C ),
a
145.33(Cb), 189.74(CO), 137.88(C1), 129.89(C2, C6), 130.38(C3, C5),
100.18(C4), 134.60(C0 ), 127.44(C0 ; C0 ), 137.88(C0 ; C0 ), 130.13(C0 ).
Weight of catalyst (g)
1
2
6
3
5
4
Fig. 3. Effect of catalyst loading.
Spectral linearity
In the present study the spectral linearity of chalcones has been
studied by evaluating the substituent effects [2a,3,4,9,12,27,29,47–
50] on the group frequencies. The assigned group frequencies of all
(E)-1-(4-iodophenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one(35):
IR(KBr, cmꢁ1
= 1670.35(COs-cis), 1578.00(COs-trans), 1111.00
(CHip), 815.89(CHop), 1004.91(CH@CHop), 592.15(C@Cop); 1H
NMR(400 MHz, CDCl3, ppm) d = 7.668(1H, , d), 7.837(1H, b, d),
7.124–7.839(8H, m, Ar-H), 4.867(1H, s, AOH); 13C NMR(100 MHz,
)
m
chalcones line infrared carbonyl stretches
deformation modes of vinyl part CHout of plane
>C@C<out
(cmꢁ1), NMR chemical shifts d(ppm) of H , Hb,
m
COs-cis
s-trans, the
and
a
,
in-plane, CH@CH and
of planes
a
CDCl3, ppm) d = 121.81(C ), 143.95(Cb), 189.25(CO), 137.94(C1),
a
129.76(C2, C6), 144.03(C3, C5), 101.15(C4), 134.60(C01), 128.55
C , Cb, CO are assigned and these frequencies are correlated with
a
(C02; C06), 130.81(C30 ; C50 ), 143.48(C04).
various substituent constants.
(E)-1-(4-iodophenyl)-3-(2-methoxyphenyl)prop-2-en-1-one(36):
IR(KBr,cmꢁ1
)
m
= 1660.71(COs-cis), 1589.34(COs-trans), 1109.50(CHip),
815.90(CAHop), 1008.77(CH@CHop), 534.328(C@Cop); 1H NMR
(400 MHz CDCl3, ppm) d = 7.554(1H, , d), 8.113(1H, b, d), 6.943–
7.851(8H, m, Ar-H), 3.923(s, 3H, OCH3); 13C NMR(100 MHz, CDCl3,
UV–Vis and IR spectral study
The measured absorption maxima (kmax nm) of these chalcones
are presented in Table 3. These values are correlated with Ham-
mett substituent constants and F and R parameters using single
a

K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
249
Table 1
Analytical and mass spectral data of chalcones synthesized by SiO2–H3PO4 catalyzed aryl methyl ketones and substituted benzaldehydes reaction of the type
ArCOCH3 + Ar0CHO ? ArCOCH@CHAr0 under microwave irradiation.
Entry Ar
Ar0
Product
MW Yield M.p. (°C)
Mass (m/z)
(%)
1
2
3
C6H5
C6H5
C6H5COCH@CHC6H5
C6H5COCH@CHC6H4Cl
C6H5COCH@CHC10H7
208 86
242 86
273 85
55–56
(55–58)[1]
114–115
(112–114) [1]
104–105
–
–
–
C6H5
C6H5
4-ClC6H4
C10H7(1-
Naph)
(104-105) [1]
122–123
(122) [1]
164-165
(164) [1]
120–121
(119–120) [1]
98–99
4
5
6
7
8
C6H5
4-OHC6H4
C6H5COCH@CHC6H4OH
291 84
291 84
213 82
223 82
294 82
–
–
–
–
–
C6H5
4-OCH3C6H4 C6H5COCH@CHC6H4OCH3
C4H3(3-Furyl) 4-NH2C6H4COCH@CHC4H3O
4-NH2C6H5
4-NH2C6H4
4-NH2C6H4
C6H5
4-
4-NH2C6H4COCH@CHC6H5
(98–99) [1]
90–91
4-
N(C2H5)2C6H4 NH2C6H4COCH@CHC6H4N(C2H5)2
(90–91) [1]
98–99
(98–99) [1]
99–100
9
4-NH2C6H4
2,6-Cl2C6H3 4-NH2C6H4COCH@CHC6H3Cl2
291 80
83
–
–
10
4-ClC6H4 C6H5 4-
ClC6H4COCH@CHC6H5 242
(98–100) [1]
49–50
(49–50) [1]
80–82
(80–81) [1]
100–101
(100–101) [1]
63–64
(63–64) [1]
100–102
(100–102) [1]
103–104
(103–104) [1]
122–123
(122–123) [1]
113–114
(113–114) [1]
98–99
(98) [1]
104–105
(104–105) [1]
67–68
(67–68) [1]
123–124
(123–124) [1]
150–151
(150–151) [1]
153–154
(153–154) [1]
80–81
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
4-F-C6H4
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
4-BrC6H4
4-FC6H4COCH@CHC6H5
2,4-Cl2C6H3COCH@CHC6H5
3,4-Cl2C6H3COCH@CHC6H5
4-(OH)C6H4COCH@CHC6H5
C10H7COCH@CHC6H5
226 83
276 84
276 84
226 84
258 84
396 55
292 44
310 83
284 84
258 84
310 85
284 84
296 80
284 85
198 85
210 84
204 85
308 82
292 86
334 87
413 86
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
2, 4-Cl2C6H3
3, 4-Cl2C6H3
4-(OH)C6H4
C10H7
(1-Naph)
4-BrC10H6
(1-Naph)
4-ClC10H6
(1-Naph)
4-OCH3C10H6
(1-Naph)
4-BrC10H6COCH@CHC6H5
4-ClC10H6COCH@CHC6H5
4-OCH3C10H6COCH@CHC6H5
4-CH3C10H6COCH@CHC6H5
C10H7COCH@CHC6H5
4-CH3C10H6
(1-Naph)
C10H7
(2-Naph)
6-OCH3C10H6
(2-Naph)
6-CH3C10H6
(2-Naph)
6-OCH3C10H6COCH@CHC6H5
6-CH3C10H6COCH@CHC6H5
C13H9COCH@CHC6H5
C
13H9
(2-Fluorene)
12H9
C
C12H9COCH@CHC6H5
(Biphenyl)
C4H3O(2-Furyl)
C4H3OCOCH@CHC6H5
(80–81) [1]
137–138
(137–138) [1]
112–113
(112–113) [1]
124–125
(124–125) [1]
107–110
5-CH3C4H2N
(2-Pyrrole)
C4H3S(2-Thienyl)
5-CH3C4H2NCOCH@CHC6H5
C4H3SCOCH@CHC6H5
C14H9(Anthracene)
C14H9 COCH@CHC6H5
5-BrC4H2S
(2-Thienyl)
4-IC6H4
5-BrC4H2SCOCH@CHC6H5
4-I-C6H4COCH@CHC6H5
4-I-C6H4COCH@CHC6H4Br-4
(106–107) [1]
86–87[51]
334[M+], 256, 230, 207, 203,
131,103,77
4-IC6H4
173–174
413[M+], 415[M2+], 285, 257, 231, 209,
203, 181, 155,126.
32
33
34
35
36
4-IC6H4
4-IC6H4
4-IC6H4
4-IC6H4
4-IC6H4
4-ClC6H4
2-FC6H4
4-FC6H4
4-OHC6H4
4-I-C6H4COCH@CHC6H4Cl-4
4-I-C6H4COCH@CHC6H4F-2
4-I-C6H4COCH@CHC6H4F-4
4-I-C6H4COCH@CHC6H4OH-4
369 80
352 85
352 80
350 84
108–109
72–74
111–112
98–99
241, 231, 209, 203, 181, 155,127
352[M+], 257, 231, 225, 203, 127, 121.
352[M+], 257, 231, 225, 203, 127,121.
350[M+], 257, 231, 223, 203, 147, 93.
364[M+], 257, 237, 231, 203, 161, 133,
129, 107
2-OCH3C6H4 4-I-C6H4COCH@CHC6H4OCH3-2 364 85
73–74
(continued on next page)

250
K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
Table 1 (continued)
Entry Ar
Ar0
Product
MW Yield M.p. (°C)
Mass (m/z)
(%)
37
38
4-IC6H4
4-IC6H4
4-OCH3C6H4 4-I-C6H4COCH@CHC6H4OCH3-4 364 88
78–79[52]
135–136
364[M+], 257, 237, 231, 203, 161, 133,
129,107
348[M+], 257, 231, 221, 203, 145, 127,
117, 91
4-CH3C6H4
4-I-C6H4COCH@CHC6H4CH3-4
348 80
Table 2
Reusability of catalyst on condensation of 4-iodoacetophenone(2 mmol) and benz-
aldehydes (2 mmol) under microwave irradiation (entries 30–38).
O
H
Run
1
2
3
4
5
Yield
87
87
86.5
86.5
86
H
I
O
CH3
and multi-linear regression analysis [11,12,26–29]. Hammett cor-
relation involving the group frequencies and absorption maxima,
the form of the Hammett equation employed is
Fig. 4. The resonance-conjugative structure.
k ¼
q
r
þ ko
ð1Þ
These data have been correlated with Hammett substituent
constants and Swain–Lupton constants [53] (see Table 4.). In this
correlation the structure parameter Hammett equation employed
is as shown in the following equation:
where ko is the frequency for the parent member of the series.
The results of statistical analysis[2,3,5,9,12,27–29,47–50] of
these values with Hammett substituent constants, F and R param-
eters, the Hammett
r constants correlated satisfactorily with
r = 0.969. The remaining parameters were failing in the correlation.
This is due to the polar, filed, resonance and inductive effects of the
substituents were weak for predicting the reactivity on the absorp-
tion. This is evident with resonance conjugative structure shown in
Fig. 4. The multi regression analysis of these frequencies of all ke-
tones with inductive, resonance and Swain–Lupton’s [53] con-
stants produce satisfactory correlations as evident in
m
¼
q
r
þ
m0
ð4Þ
where
the corresponding quantity of unsubstitued system;
substituent constant, which in principle is characteristics of the
substituent and is a reaction constant which is depend upon the
m
is the carbonyl frequencies of substituted system and
m
0 is
r
is a Hammett
q
nature of the reaction.
The results of single parameter statistical analysis of carbonyl
ðnmÞ
k
¼ 300:506ðꢂ15:572Þ þ 40:321ðꢂ14:968ÞrI
ꢁ 6:259ðꢂ4:557ÞrR ðR
¼ 0:942; n ¼ 9; P > 90%Þ
max
frequencies with Hammett
poor correlations (see Table 4). A satisfactory correlation was
found for s-trans conformers with , (r = 0.983) and
+(r = 0.987)
r constants, F and R parameters gave
r
r
ð2Þ
ð3Þ
values. The remaining parameters were fail in correlations. The
failure in correlation is due the conjugation between the substitu-
ent and the carbonyl group in chalcones as shown in Fig. 4.
A satisfactory correlation obtained for CHin-plane modes with
ðnmÞ
k
¼ 300:086ðꢂ15:911Þ þ 12:221ðꢂ3:362ÞF
ꢁ 25:691ðꢂ4:469ÞR ðR
¼ 0:939; n ¼ 9; P > 90%Þ
max
Hammett
r (r = 0.956), r+(r = 0.946), rI(r = 0.963), constants and
F (r = 0.968) parameter. The remaining Hammett substituent con-
stants gave poor correlation due to the conjugation. A satisfactory
correlation was found for CHout-plane modes with Hammett
IR spectral study
The carbonyl stretching frequencies (cmꢁ1) of s-cis and s-trans
isomers of present study are presented in Table 3 and the corre-
sponding conformers are shown in Fig. 5. The stretching frequen-
cies for carbonyl absorption are assigned based on the
assignments made by Hays and Timmons [54] for s-cis and s-trans
conformers at 1690 and 1670 cmꢁ1, respectively.
rR(r = 0.900), constant and R (r = 0.900) parameter. The remaining
parameters were fail in correlations. A satisfactory correlation ob-
tained for CH@CH out of plane with Hammett rR constant, F and R
parameters gave satisfactory correlation co-efficients r = 0.900,
r = 0.902 and r = 0.900. The C@C out of plane modes with Hammett
rR constant, F and R parameter correlation is satisfactorily with the
Table 3
The UV (kmax, nm) absorption and IR (m
, cmꢁ1) spectroscopic data of substituted styryl 4-iodophenyl ketones (entries 30–38).
Entry
X
kmax
COs-cis
COs-trans
CHip
CHop
CH@CHop
C@Cop
30
31
32
33
34
35
36
37
38
H
4-Br
4-Cl
2-F
318
321
320
312
316
349
301
327
267
1627.92
1654.72
1666.50
1660.71
1654.92
1670.35
1660.71
1640.37
1653.01
1597.10
1604.77
1598.31
1602.90
1593.20
1578.00
1589.34
1593.22
1591.33
1122.57
1103.28
1105.21
1095.60
1103.31
1111.00
1109.50
1134.10
1114.90
756.10
798.53
813.32
813.96
823.60
815.89
815.90
812.03
815.89
1002.98
1010.70
1056.99
1002.98
987.55
1004.91
1008.77
1006.84
1018.41
551.64
543.93
536.21
511.14
514.99
592.15
534.28
524.64
530.42
4-F
4-OH
2-OCH3
4-OCH3
4-CH3

K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
251
O
O
H
H
I
H
I
X
s-trans
X
s-cis
Fig. 5. The s-cis and s-trans conformers of substituted styryl 4-iodophenyl ketones.
Table 4
Results of statistical analysis of infrared m r, , rI,
(cmꢁ1) COs-cis, COs-trans, CHip, CHop, CH@CHop and C@Cop substituted styryl 4-iodophenyl ketones (entries 30–38) with Hammett r+
rR constants and F and R parameters.
Frequency
COs-cis
Constants
r
I
q
s
n
Correlated derivatives
r
0.745
0.801
0.811
0.751
0.801
0.855
1654.36
1654.26
1644.51
1645.25
1645.69
1643.88
0.173
14.04
14.04
11.97
12.42
12.30
12.16
9
9
9
9
9
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl,2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
r+
rI
rR
F
ꢁ0.474
32.120
ꢁ29.069
23.857
ꢁ26.117
R
COs-trans
r
0.983
0.987
0.833
0.798
0.825
0.752
0.956
0.964
0.963
0.825
0.968
0.817
0.815
0.825
0.745
0.900
0.805
0.900
0.824
0.802
0.800
0.900
0.902
0.900
0.801
0.804
0.824
0.900
0.900
0.900
1595.23
1596.95
1590.31
1598.37
1590.97
1600.23
1110.03
1108.12
1121.68
1114.83
1121.92
1114.25
806.75
26.568
13.411
12.677
13.315
8.888
15.033
ꢁ25.979
ꢁ14.198
ꢁ34.689
12.084
ꢁ29.951
7.995
ꢁ12.656
ꢁ9.905
45.556
ꢁ62.995
40.010
ꢁ55.732
20.372
3.394
4.68
4.12
8.08
8.04
8.21
7.57
10.21
9.50
9.54
9
8
9
9
9
9
7
7
8
9
8
9
9
9
9
8
9
8
9
9
9
8
8
8
9
9
9
8
8
8
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-CH3
r+
rI
rR
F
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl,2-F, 4-F,4-OH, 2-OCH3, 4-CH3
H, 4-Br, 4-Cl,2-F, 4-F,4-OH,2 -OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F,4-OH, 2-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F,4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
4-Br, 4-Cl,2-F, 4-F,4-OH,2-OCH3,4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
4-Br, 4-Cl,2-F, 4-F,4-OH,2-OCH3,4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F,4-OH, 2-OCH3, 4-CH3
R
r
CHip
r+
rI
rR
F
12.10
9.04
R
r
12.22
21.40
20.95
19.01
16.36
18.46
15.66
19.62
20.29
20.38
18.81
19.95
18.22
23.36
23.25
24.52
25.39
23.47
25.78
CHop
r+
rI
rR
F
805.21
793.27
787.51
792.71
R
r
784.89
CH@CHop
1011.92
1011.82
1010.97
1022.00
1016.48
1024.73
536.14
533.63
548.45
543.98
551.38
r+
rI
rR
F
0.513
34.706
ꢁ14.748
33.928
ꢁ40.339
ꢁ19.863
ꢁ35.022
20.028
ꢁ37.645
1.855
R
r
C@Cop
r+
rI
rR
F
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-CH3
R
538.45
r = correlation coefficient;
q = slope; I = intercept; s = standard deviation; n = number of substituents.
ðcmꢁ1
s-cis
Þ
r values of 0.900, 0.900, 0.900 respectively. The remaining Ham-
mett substituent constants gave poor correlation due to the conju-
gation between the substituent and the vinyl group in chalcones as
shown in Fig. 5.
m
CO
CO
¼ 1642:023ðꢂ8:451Þ ꢁ 23:500ðꢂ4:403ÞrI
ꢁ 16:356ðꢂ4:723ÞrR
ðR ¼ 0:956; n ¼ 9; P > 95%Þ
ð5Þ
ð6Þ
In view of the inability of some of the
individually satisfactory correlations, it was thought that worth-
while to seek multiple correlations involving either I and rR con-
r constants to produce
ðcmꢁ1
s-cis
Þ
m
¼ 1642:235ðꢂ8:628Þ þ 14:240ðꢂ2:803ÞF
ꢁ 17:316ðꢂ2:946ÞR
ðR ¼ 0:955; n ¼ 9; P > 95%Þ
r
stants or Swain–Lupton’s [53], F and R parameters. The correlation
equations for s-cis, s-trans and deformation modes are given in

252
K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
ðcmꢁ1
Þ
Table 5
m
m
m
CO
¼ 1594:593ðꢂ4:406Þ þ 27:548ðꢂ12:725ÞrI
s-trans
NMR chemical shifts d(ppm) of substituted styryl 4-iodophenyl ketones (entries 30–
40).
þ 28:217ðꢂ12:891ÞrR
ðR ¼ 0:971; n ¼ 9; P > 95%Þ
ð7Þ
ð8Þ
Entry
X
dH
dHb
X
dC
dCb
dCO
X
a
a
30
31
32
33
34
35
36
H
7.740 7.877
7.564 7.878
7.579 7.879
7.745 7.883
7.393 7.780
–
–
–
–
–
121.48 145.47 189.75
121.90 144.00 189.44
121.81 143.95 189.25
122.68 138.00 189.61
121.14 144.13 189.50
–
–
–
–
–
–
ðcmꢁ1
s-trans
Þ
CO
¼ 1597:200ðꢂ3:374Þ þ 26:243ðꢂ8:135ÞF
þ 31:251ðꢂ8:582ÞR
ðR ¼ 0:984; n ¼ 9; P > 95%Þ
4-Br
4-Cl
2-F
4-F
4-OH
2-
OCH3
4-
OCH3
4-CH3
7.668 7.837 4.867 121.81 143.95 189.25
7.554 8.113 3.923 120.81 141.09 190.41 55.60
7.425 7.799 3.864 120.45 145.59 189.33 55.47
6.943 7.604 2.401 119.12 145.33 189.74 21.61
ðcmꢁ1Þ
CH
¼ 1120:261ðꢂ6:852Þ ꢁ 39:614ðꢂ9:787ÞrI
ꢁ 9:345ðꢂ2:046ÞrR
ðR ¼ 0:965; n ¼ 9; P > 95%Þ
ip
37
38
ð9Þ
ðcmꢁ1Þ
m
m
m
m
m
m
m
CH
CH
CH
¼ 1118:732ðꢂ6:143Þ ꢁ 38:842ðꢂ14:812ÞF
þ 16:010ðꢂ5:625ÞR
ðR ¼ 0:974; n ¼ 9; P > 95%Þ
ip
Logd ¼ Logd0 þ
q
r
ð17Þ
ð10Þ
ð11Þ
where d0 is the chemical shift of unsubstitued ketones.
ðcmꢁ1Þ
¼ 785:136ðꢂ11:710Þ þ 17:281ðꢂ13:814ÞrI
ꢁ 53:646ðꢂ34:257ÞrR
ðR ¼ 0:967; n ¼ 9; P > 95%Þ
The assigned H and Hb proton chemical shifts (ppm) are corre-
lated with various Hammett sigma constants. The results of statis-
tical analysis [2,3,5,9,12,27–29,47–49] are presented in Table 6.
a
op
The obtained correlations were poor for H and Hb with Hammett
a
r
constants, F and R parameters. The failure in correlation for both
ðcmꢁ1
Þ
¼ 783:298ðꢂ11:295Þ þ 13:794ðꢂ7:233ÞF
ꢁ 47:207ðꢂ28:728ÞR
ðR ¼ 0:970; n ¼ 9; P > 95%Þ
the proton chemical shifts and is due to the reasons stated in ear-
lier and the conjugative structure shown in Fig. 4.
op
Application of Swain–Lupton’s [53]treatment to the relative
ð12Þ
ð13Þ
ð14Þ
ð15Þ
ð16Þ
chemical shifts of H and Hb with F and R values is successful with
a
resonance, inductive and fail with F and R parameter generates the
multiregression equations
ðcmꢁ1
Þ
CH@CH
¼ 1018:391ðꢂ13:247Þ þ 26:304ðꢂ18:253ÞrI
op
þ 48:935ðꢂ18:754ÞrR
ðR ¼ 0:945; n ¼ 9; P > 90%Þ
dðHppmÞ ¼ 7:375ðꢂ0:177Þ þ 1:459ðꢂ0:511ÞrI
a
þ 0:910ðꢂ0:517ÞrR
ðcmꢁ1
Þ
ðR ¼ 0:935; n ¼ 9; P > 90%Þ
ð18Þ
ð19Þ
CH@CH
¼ 1024:015ðꢂ13:383Þ þ 6:232ðꢂ2:267ÞF
op
þ 7:779ðꢂ34:039ÞR
ðR ¼ 0:945; n ¼ 9; P > 90%Þ
dðHppmÞ ¼ 7:416ðꢂ0:183Þ þ 0:331ðꢂ0:044ÞF
a
þ 1:060ðꢂ0:670ÞR
ðcmꢁ1
Þ
Þ
ðR ¼ 0:932; n ¼ 9; P > 90%Þ
C@C
¼ 548:681ðꢂ17:927Þ ꢁ 34:223ðꢂ11:767ÞrI
þ 51:515ðꢂ52:444ÞrR
ðR ¼ 0:931; n ¼ 9; P > 90%Þ
op
ðppmÞ
d
¼ 7:749ðꢂ0:092Þ þ 0:955ðꢂ0:265ÞrI
Hb
ꢁ 0:229ðꢂ0:026ÞrR
ðR ¼ 0:946; n ¼ 9; P > 90%Þ
ðcmꢁ1
ð20Þ
C@C
¼ 544:890ðꢂ16:482Þ ꢁ 55:748ðꢂ19:741ÞF
op
ꢁ 32:598ðꢂ11:923ÞR
ðR ¼ 0:949; n ¼ 9; P > 90%Þ
ðppmÞ
Hb
d
¼ 7:801ðꢂ0:102Þ þ 0:049ðꢂ0:002ÞF
ꢁ 0:078ðꢂ0:002ÞR
ðR ¼ 0:922; n ¼ 9; P > 90%Þ
ð21Þ
1H NMR spectral study
The 1H NMR spectra of synthesized chalcones were recorded in
deuteriochloroform solutions employing tetramethylsilane (TMS)
as internal standard. The signals of the ethylenic protons were as-
signed from their spectra. They were calculated as AB or AA0 or BB0
systems respectively. The lower chemical shifts (ppm) obtained for
13C NMR spectral study
Spectral analysts,
organic
chemists
and
scientists
[2,3,5,9,12,27–29,47–50] have made extensive study of 13C NMR
spectra for a large number of different ketones and styrenes. The
assigned vinyl C , Cb and carbonyl carbon chemical shifts are pre-
H
a
and higher chemical shifts (ppm) obtained for Hb in this series
a
sented in Table 5. The results of statistical analysis are given in Ta-
of ketones. The vinyl protons give an AB pattern and the b-proton
doublets were well separated from the signals of the aromatic pro-
tons. The assigned vinyl proton chemical shifts d(ppm) of all ke-
tones were presented in Table 5.
ble 6. The C chemical shifts(ppm) gave satisfactory correlation
a
with Hammett substituent constants
chemical shifts (ppm) of Cb carbon with Hammett
and R parameters were gave poor correlation with negative
r(r = 0.945), r
+(0.908). The
r
constants, F
In nuclear magnetic resonance spectra, the proton or the 13C
chemical shifts (d) depends on the electronic environment of the
nuclei concerned. The assigned vinyl proton chemical shifts
(ppm) have been correlated with reactivity parameters using Ham-
mett equation in the form of
q
val-
ues. This is due to reasons stated earlier with the resonance conju-
gative structure shown in Fig. 4. The carbonyl carbon chemical
shifts (ppm) of all ketones gave poor correlation with Hammett
r
constants, F and R parameters.

K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
253
Table 6
Results of statistical analysis of infrared d(ppm) of ethylenic protons, carbons and carbonyl carbons of substituted styryl 4-iodophenyl ketones (entries 30–38) with Hammett
rR constants and F and R parameters.
r,
r+
, rI,
Frequency
Constants
r
I
q
s
n
Correlated derivatives
dðHppmÞ
r
0.813
7.517
0.131
0.26
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
a
r+
rI
rR
F
0.842
0.834
0.824
0.835
0.814
7.553
7.373
7.438
7.404
7.454
0.201
0.454
0.23
0.24
0.25
0.24
0.26
9
9
9
9
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
ꢁ0.238
0.297
R
ꢁ0.144
dðppmÞ
r
0.798
7.846
ꢁ0.097
0.13
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
Hb
r+
rI
rR
F
0.822
0.825
0.844
0.821
0.798
7.862
7.784
7.762
7.816
7.807
0.057
0.216
0.13
0.13
0.12
0.14
0.13
9
9
9
9
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
ꢁ0.280
0.093
R
ꢁ0.108
dðCppmÞ
r
0.945
121.31
1.849
0.98
7
H, 4-Br, 4-Cl, 2-F, 4-F, 2-OCH3, 4-OCH3
a
r+
rI
rR
F
0.908
0.864
0.812
0.860
0.781
121.51
120.28
121.95
120.38
120.94
1.276
3.125
0.84
0.84
1.08
0.87
1.08
7
9
9
9
9
H, 4-Br, 4-Cl, 2-F, 4-F, 2-OCH3, 4-OCH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
ꢁ0.919
2.355
R
ꢁ0.742
dðCppmÞ
r
0.842
143.42
ꢁ1.952
2.58
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
b
r+
rI
rR
F
0.846
0.849
0.857
0.859
0.845
143.04
145.26
145.59
145.51
145.29
ꢁ2.206
ꢁ5.737
6.686
2.32
2.28
2.16
2.11
2.34
9
9
9
9
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
ꢁ5.539
R
4.476
ðppmÞ
r
0.833
189.56
ꢁ0.479
0.36
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
d
CO
r+
rI
rR
F
0.803
0.829
0.829
0.825
0.803
189.58
189.73
189.47
189.71
189.60
ꢁ0.027
ꢁ0.491
-0.362
ꢁ0.354
0.049
0.38
0.37
0.37
0.37
0.38
9
9
9
9
9
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
H, 4-Br, 4-Cl, 2-F, 4-F, 4-OH, 2-OCH3, 4-OCH3, 4-CH3
R
r = correlation coefficient;
q = slope; I = intercept; s = standard deviation; n = number of substituents.
The Swain Lupton’s [53] parameter correlations were satisfacto-
rily obtained within these carbon chemical shifts and the regres-
sion equations are given in
Antimicrobial activities
Chalcones possess a wide range of biological activities such as
antibacterial [55], antifungal [55], antiviral [56], antifeedant [57],
anticancer [55], antimalarial [58], antituberclosis [59], antiAIDS
[60] and antioxidant [61] activities. These multipronged activities
present in different chalcones are examined against respective mi-
crobes – bacteria’s and fungi.
dCaðppmÞ ¼ 120:449ðꢂ0:596Þ þ 3:693ðꢂ1:723ÞrI
þ 1:078ðꢂ0:745ÞrR ðR
¼ 0:967; n ¼ 9; P > 95%Þ
ð22Þ
ð23Þ
ð24Þ
dCðappmÞ ¼ 120:605ðꢂ20:623Þ þ 2:958ðꢂ1:503ÞF
þ 1:086ðꢂ0:585ÞR ðR
Antibacterial sensitivity assay
Antibacterial sensitivity assay was performed using Kirby–Bau-
er [62] disc diffusion technique. In each Petri plate about 0.5 mL of
the test bacterial sample was spread uniformly over the Solidified
Mueller Hinton agar using sterile glass spreader. Then the discs
with 5 mm diameter made up of Whatmann No. 1 filter paper,
impregnated with the solution of the compound (15 mg per
1 mL) were placed on the medium using sterile forceps. The plates
were incubated for 24 h at 37 °C by keeping the plates upside down
to prevent the collection of water droplets over the medium. After
24 h, the plates were visually examined and the diameter values of
the zone of inhibition were measured. Triplicate results were re-
corded by repeating the same procedure.
The antibacterial screening effect of synthesized chalcones is
shown in Fig. 6, Plates (1–10). The zone of inhibition is compared
using Table 7. A good antibacterial activity has been possessed
by all substituents on the microorganisms in general. All the com-
pounds except those with 4-Cl and 4-OCH3 substituents, showed
good activities on micrococcus luteus species. All the compounds
except those with H and 2-F substituents, showed good activities
against Escherichia coli. The compounds with 4-F, 4-OH and 4-
OCH3 substituents have improved antibacterial activity against
¼ 0:964; n ¼ 9; P > 95%Þ
dCðbppmÞ ¼ 146:021ðꢂ14:520Þ ꢁ 3:094ðꢂ0:390ÞrI
þ 5:013ðꢂ1:447ÞrR ðR
¼ 0:965; n ¼ 9; P > 95%Þ
dCðbppmÞ ¼ 145:833ðꢂ11:539Þ ꢁ 4:648ðꢂ1:711ÞF
þ 1:603ðꢂ0:415ÞR ðR
¼ 0:961; n ¼ 9; P > 95%Þ
ð25Þ
ð26Þ
dCOðppmÞ ¼ 189:604ðꢂ20:242Þ ꢁ 0:954ðꢂ0:069ÞrI
ꢁ 0:878ðꢂ0:070ÞrR ðR
¼ 0:952; n ¼ 9; P > 95%Þ
dCOðppmÞ ¼ 189:664ðꢂ20:272Þ ꢁ 0:497ðꢂ0:065ÞF
ꢁ 1:258ðꢂ0:603ÞR ðR
¼ 0:920; n ¼ 9; P > 90%Þ
ð27Þ

254
K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
PLATE-1
PLATE-3
PLATE-5
PLATE-2
PLATE-4
PLATE-6
PLATE-7
PLATE-8
PLATE-9
PLATE-10
Fig. 6. Antibacterial activity of substituted styryl 4-iodophenyl ketones-petri dishes.

K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
255
Table 7
The antibacterial activities of styryl 4-iodophenyl ketones (entries 30–38).
Table 8
Antifungal activities of substituted styryl 4-iodophenyl ketones (entries 30–38).
Entry
X
Zone of inhibition (mm)
Gram positive bacteria
S. No.
X
Zone of Inhibition (mm)
Gram negative
bacteria
A. niger
Pen. Scup
30
31
32
33
34
35
36
37
38
H
4-Br
4-Cl
2-F
6
–
11
9
B. subtilis M. luteus S. aureus E. coli P. aeruginosa
–
–
30
31
32
33
34
35
36
37
38
H
4-Br
4-Cl
2-F
7
–
8
7
7
–
7
–
8
7
–
7
8
–
8
–
7
8
–
4-F
7
8
8
–
8
7
4-OH
2-OCH3
4-OCH3
4-CH3
Miconazole
DMSO
7
–
6
–
12
11
10
–
7
8
–
–
4-F
8
7
7
8
4-OH
2-OCH3
4-OCH3
4-CH3
12
13
12
11
10
7
–
7
8
8
–
12
–
13
–
7
8
8
7
7
Ampicillin 19
DMSO
17
–
13
–
16
–
14
–
–
column chart reveals that only a few compounds under investiga-
tion have excellent antifungal activity against all the two fungal
species namely Aspergillus niger, and pen.scup. The Chalcones with
AH, 4-Br, 4-F, 4-OH, 2-OCH3 and 4-OCH3 substituents have shown
appreciable antifungal activity against pen.scup. Compound con-
taining 2-F substituent alone has shown good activity against A.
niger.
Pseudomonas aerogenosa. The compounds with 4-F and 4-CH3 sub-
stituents showed moderate activity against Staphylococcus aureus.
All the compounds except those with 4-Br substituent, showed
very good activities on Bacillus subtillis species.
Antifungal sensitivity assay
Antifungal sensitivity assay was performed using Kirby–Bauer
[62] disc diffusion technique. PDA medium was prepared and ster-
ilized as above. It was poured (ear bearing heating condition) in the
Petri-plate which was already filled with 1 mL of the fungal spe-
cies. The plate was rotated clockwise and counter clock-wise for
uniform spreading of the species. The discs were impregnated with
the test solution. The test solution was prepared by dissolving
15 mg of the chalcone in 1 mL of DMSO solvent. The medium
was allowed to solidify and kept for 24 h. Then the plates were
visually examined and the diameter values of zone of inhibition
were measured. Triplicate results were recorded by repeating the
same procedure.
Conclusions
We have developed an efficient crossed-aldol condensation for
synthesis of chalcones using a versatile solid SiO2–H3PO4 acid cat-
alyst. The yield of the reaction is more than 85%. The effects of sub-
stituent on the group frequencies and the antimicrobial activities
of 40-iodophenyl chalcones have been studied.
Acknowledgement
The authors thank DST NMR Facility, Department of Chemistry
and CSIL, Annamalai University, Annamalainagar-608002, for
recording NMR spectra of all compounds and SEM analysis of
catalyst.
The antifungal activities of substituted chalcones synthesized in
the present study are shown in Fig. 7 for Plates (1–4) and the zone
of inhibition values of the effect is given in Table 8. The clustered
PLATE-1
PLATE-2
PLATE-3
PLATE-4
Fig. 7. Antifungal activity of substituted styryl 4-iodophenyl ketones-petri dishes.

256
K. Sathiyamoorthi et al. / Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 112 (2013) 245–256
[31] A. Sharma, V.P. Gupta, A. Virdi, Indian J. Pure Appl. Phys. 40 (2005) 246.
References
[32] G.K. Dass, Indian J. Chem. 40 (A) (2001) 23.
[33] P.R. Griffiths, J.M. Chalmers, Handbook of Vibrational Spectroscopy, vol. 4,
John-Wiley & Sons Inc., Chinchester, 2002. 2576.
[34] C. Pellerin, I. Pelletier, Lab Plus International, vol. 19, Reed Elsevier
[1] G. Thirunarayanan, P. Mayavel, K. Thirumurthy, Spectrochim. Acta 91A (2012)
18.
[2] (a) K. Ranganathan, R. Arulkumaran, D. Kamalakkannan, R. Sundararajan, S.P.
Sakthinathan, S. Vijayakumar, R. Suresh, G. Vanangamudi, K. Thirumurthy, P.
Mayavel, G. Thirunarayanan, Int. J. Pharm. Med. Bio.Sc. 1 (1) (2012) 62;
(b) M.R. Jayapal, N.Y. Sreedha, Asian J. Pharm. Clin. Res. 4 (1) (2011) 106;
(c) G. Thirunarayanan, J. Indian Chem. Soc. 84 (2008) 447.
[3] G. Thirunarayanan, M. Gopalakrishnan, G. Vanangamudi, Spectrochim. Acta
67A (2007) 1106.
[4] G. Thirunarayanan, P. Ananthakrishna Nadar, Asian J. Chem. 3–4 (2002) 1518.
[5] G. Venkat Reddy, G. Maitraie, D. Narsaiah, B. Rambahu, R. Rao, Synth. Commun.
31 (18) (2001) 2881.
[6] S. Kobayashi, H. Kiyohara, M. Yamaguchi, J. Am. Chem. Soc. 133 (2011) 708.
[7] W. Li, W. Wu, J. Yang, X. Liang, J. Ye, Synthesis (2011) 1085.
[8] S.H. Leung, S.A. Angel, J. Chem. Edn. 81 (2004) 1492.
[9] G. Thirunarayanan, J. Korean Chem. Soc. 52 (4) (2008) 369.
[10] G. Thirunarayanan, G. Vanangamudi, Arkivoc 12 (2006) 58.
[11] P. Salehi, M. Dabiri, M.A. Zolfigol, M.A.B. Fard, J. Braz. Chem. Soc. 15 (5) (2004)
773.
[12] G. Thirunarayanan, P. Ananthakrishna Nadar, J. Indian Chem. Soc. 83 (2006)
1107.
[13] D.R. Palleros, J. Chem. Educ. 81 (9) (2004) 1345.
[14] S.A. Basaif, T.R. Sobahi, A.K. Khalil, M.A. Hassan, Bull. Korean Chem. Soc. 26 (11)
(2005) 1677.
[15] Q. Xu, Z. Yang, D. Yin, F. Zhang, Catal. Commun. 9 (1) (2008) 1579.
[16] P. Kumar, S. Kumar, K. Husain, A. Kumar, Bioorg. Med. Chem. 18 (2011) 4965.
[17] Z. Zhang, Y.W. Dong, G.W. Wang, Chem. Lett. 32 (10) (2003) 966.
[18] H.E. Blackwell, Curr. Opinion Chem. Biol. 10 (3) (2006) 203.
[19] G. Thirunarayanan, Proceedings of the 46th Annual Convention of Chemists
and International Conference on Recent Research Trends in Chemical Sciences’’
No. ORG OP5, 2009, pp.C13.
[20] B.F.G. Johnson, J. Lewis, G.R. Stephenson, E.J.S. Vichi, J. Chem. Soc. Dalton Trans.
(1978) 369.
[21] N.S. Fernandes, M.A.S. CarvalhoFilho, R.A. Mendes, C.B. Meliosand, M.
Ionashiro, J. Thermal Anal. Calorim. 76 (2010) 193.
[22] Y. Xiuying, P. An-shun, J. Linyi Teachers Coll. 23 (2004) 621.
[23] B. Krishnakumar, R. Velmurugan, M. Swaminathan, Catal. Commun. 12 (5)
(2011) 375.
[24] J.K. Rajput, G. Kaur, Tetrahedron Lett. 53 (2012) 646.
[25] M. Sivakumar, S. Phrabusreeneivasan, V. Kumar, M. Doble, Bioorg. Med. Chem.
Lett. 17 (10) (2007) 3169.
[26] X. Liu, M.L. Go, Bioorg. Med. Chem. 14 (2006) 153.
[27] K. Ranganathan, K. Arulkumaran, D. Kamalakkannan, G. Vanangamudi, G.
Thirunarayanan, Iup. J. Chem. 4 (2) (2011) 60.
[28] J. Deng, T. Sanchez, Q.A.M. Lalith, Bioorg. Med. Chem. 15 (14) (2007) 4985.
[29] K. Ranganathan, R. Suresh, D. Kamalakkannan, R. Arulkumaran, R.
Sundararajan, S.P. Sakthinathan, S. Vijayakumar, G. Vanangamudi, K.
Thirumurthy, P. Mayavel, G. Thirunarayanan, Int. Lett. Chem. Phys.
Astronom. 4 (2012) 66.
Publications, UK, 2005. p. 108.
´
´
[35] V. Horvath, Z. Varga, A. Kovacs, J. Mol. Struct. (Theochem.) 755 (1-3) (2005)
247.
[36] Y.H. Wang, J.W. Zou, B. Zhang, Y.X. Lu, H.X. Jin, Q.S. Yu, J. Mol. Struct.
(Theochem.) 755 (1–2) (2005) 31.
[37] J.C. Chen, L. Qian, W.J. Wu, L.M. Chen, K.C. Zheng, J. Mol. Struct. (Theochem.)
755 (1–3) (2005) 167.
[38] E. Dumont, P. Chaquin, J. Mol. Struct. (Theochem.) 758 (2-3) (2006) 161.
[39] K. Senthilkumar, M. Sethu Raman, P. Kolandaivel, J. Mol. Struct. (Theochem.)
758 (2–3) (2006) 107.
[40] M. Izadar, M.R.J. Gholami, J. Mol. Struct. (Theochem.) 755 (1–2) (2006) 11.
[41] D. Kaur, P. Sharma, P.V. Bharatam, N. Dogra, J. Mol. Struct. (Theochem.) 755 (1-
3) (2006) 41.
[42] M. Santelli, M. Delphine, E.A. Douniazad, P. Helena, J. Mol. Struct. (Theochem.)
755 (1-3) (2006) 113.
[43] K.S. Dhami, J.B. Stothers, Canadian J. Chem. 43 (1963) 479.
[44] P.C. Lauterber, J. Am. Chem. Soc. 83 (1961) 1846.
[45] V.I. Savin, R.G. Gainullina, V.V. Zuereu, J.P. Kitaev, Zh. Org. Khim. 11 (1975) 169.
[46] E. Solcaniova, S. Toma, Org. Magn. Reson. 14 (1980) 181.
[47] D. Kamalakkannan, G. Vanangamudi, R. Arulkumaran, K. Thirumurthy, P.
Mayavel, G. Thirunarayanan, Elixir Org. Chem. 46 (2012) 8157.
[48] S.P. Sakthinathan, G. Vanangamudi, G. Thirunarayanan, Spectrochim. Acta 95
(A) (2007) 693.
[49] G. Thirunarayanan, G. Vanangamudi, M. Subramanian, U. Umadevi, S.P.
Sakthinathan, R. Sundararajan, Elixir Org. Chem. 39 (2011) 4643.
[50] P. Janaki, K.G. Sekar, G. Thirunarayanan, Org. Chem.: Indian J. 9 (1) (2013) 68.
[51] M.G. Ahmed, U.K.R. Romman, S.M. Ahmed, K. Akhter, Bangladesh J. Sci. Ind.
Res. 42 (1) (2007) 45.
[52] A.N. Choudhary, V. Juyal, Int. J. Pharm. Pharm. Sci. 3 (3) (2011) 125128.
[53] C.G. Swain, E.C. Lupton Jr., J. Am. Chem. Soc. 90 (1968) 4328.
[54] W.P. Hays, C.J. Timmons, Spectrochim. Acta 24A (1968) 323.
[55] M. Sivakumar, S. Phrabusreeneivasan, V. Kumar, M. Doble, Bioorg. Med. Chem.
Lett. 17 (10) (2007) 3169.
[56] K.L. Lahtchev, D.I. Batovska, St. P. Parushev, V.M. Ubiyvock, A.A. Sibirny, Eur. J.
Med. Chem. 43 (1) (2008) 1.
[57] I. El-Subbagh Hussein, S.M. Abu-Zaid, M.A. Mahran, A. BadriaFarid, A.M. Al-
Obaid, J. Med. Chem. 43 (2002) 2915.
[58] A. Modzelewska, C. Pettit, G. Achanta, N.E. Davidson, P. Huang, S.R. Khan,
Bioorg. Med. Chem. 14 (2006) 3491.
[59] J.N. Dominguez, C. Leon, J. Rodrigues, J. IL Farmaco. 60 (4) (2005) 307.
[60] Y.M. Lin, Y. Zhon, M.T. Flavin, M. Zhon, W. Ne, F.C. Chen, Bioorg. Med. Chem. 10
(8) (2002) 2795.
[61] M.W. Weber, L.A. Hunsaker, S.F. Abcouwer, L.M. Decker, D.L. Vander Jagat,
Bioorg. Med. Chem. 13 (2005) 381.
[62] A.W. Bauer, W.M.M. Kirby, J.C. Sherris, M. Truck, Am. J. Clin. Pathol. 45 (1996)
493.
[30] C.M. Deiva, N.B. Pappano, N.B. Debattista, Rev. Microbiol. 29 (1998) 307.