Ultrasound-assisted synthesis of aromatic 1,2-diketones from oximinoketones under neutral conditions in aqueous media

Article abstract of DOI:10.1016/j.ultsonch.2011.05.011

We report a convenient, neutral, and facile methodology for the synthesis of aromatic 1,2-diketones from the corresponding oximinoketones in the presence of I₂/SDS/water system under ultrasound-assisted conditions. Furthermore, a series of comp

Full text of DOI:10.1016/j.ultsonch.2011.05.011

Ultrasonics Sonochemistry 19 (2012) 125–129
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Ultrasonics Sonochemistry
journal homepage: www.elsevier.com/locate/ultsonch
Ultrasound-assisted synthesis of aromatic 1,2-diketones from oximinoketones
under neutral conditions in aqueous media
⇑
Hossein Mehrabi
Department of Chemistry, Vali-e-Asr University of Rafsanjan, Rafsanjan 77176, Iran
a r t i c l e i n f o
a b s t r a c t
Article history:
We report a convenient, neutral, and facile methodology for the synthesis of aromatic 1,2-diketones from
the corresponding oximinoketones in the presence of I2/SDS/water system under ultrasound-assisted
conditions. Furthermore, a series of compounds were synthesized and characterized by melting point,
IR, NMR, MS, and elemental analysis. Utilization of easy reaction conditions, very high to excellent yields,
and short reaction times makes this manipulation potentially very useful.
Received 23 January 2011
Received in revised form 28 April 2011
Accepted 14 May 2011
Available online 27 May 2011
Ó 2011 Elsevier B.V. All rights reserved.
Keywords:
Ultrasound-assisted
Oximinoketones
1,2-Diketones
Sodium dodecyl sulfate (SDS)
1. Introduction
dramatic increase in the temperature and pressure during col-
lapse of the cavities are the most important effects of ultrasound
A great deal of effort has gone into the efficient preparation of
1,2-diketones, due to their biological activity and usefulness as
precursors for many useful organic transformations [1–4]. While
a wide variety of methods are described in the literature for the
preparation of 1,2-diketones [5–13], there are no literature exam-
ples of the synthesis of 1,2-diketones from oximinoketones.
Although the oxime compounds can be deprotected to the corre-
sponding carbonyl compounds by using a number of efficient re-
agents [14–20], this strategy is not free from drawbacks.
Development of a better reagent in water under neutral conditions
is desirable.
Organic reactions in aqueous media have attracted increasing
interest currently because of environmental issues and a better
understanding of biochemical processes. Water offers many practi-
cal and economic advantages as a reaction solvent, including low
cost, safe handing and environmental compatibility [21,22].
The application of ultrasound in organic synthesis has been
increasing because of its advantages, including a shorter reaction
times, milder reaction conditions, and higher yields in compari-
son to classical methods [23–25]. Since in this technique the
reaction is carried out normally at lower temperature relative
to the usually thermal methods, the possibility of occurrence of
undesired reactions is reduced, and, as a result of a cleaner reac-
tion, the workup is easier. The generation of many cavities and a
[26,27].
Recently, a new system of I2/SDS/water has been used for the
deprotection of oximes and imines to the corresponding carbonyl
compound [28]. Herein we propose to use this system both with
and without ultrasonic irradiation in the preparation of aromatic
1,2-diketones from their corresponding oximinoketones [29–31]
under neutral conditions in aqueous media (Scheme 1).
2. Experimental
2.1. General considerations
The chemicals used in this work were purchased from Merck
and Aldrich chemical companies. Melting points were determined
using a Mettler FP5 apparatus and are uncorrected. IR spectra were
determined using KBr pellets on a Shimadzu recording spectropho-
tometer, Model 435. 1H and 13C NMR (500 and 125 MHz) spectra
were recorded on a Bruker 500 spectrometer in CDCl3 with TMS
as an internal standard. Mass spectra were taken by a Platform II
from Micromass and Elemental analyses were performed using a
Carlo Erba EA 1108 instrument. The ultrasonic device used was
an UP 400 S instrument from Dr. Hielscher GmbH (with a fre-
quency of 24 or 48 kHz and a nominal power of 400 W). The reac-
tion flask was located in the ultrasonic bath, where the surface of
reactants is slightly lower than the level of the water. The reaction
temperature was controlled by the addition or removal of water
from the ultrasonic bath.
⇑
Tel.: +98 391 3202161; fax: +98 391 3202165.
E-mail address: mehraby_h@yahoo.com
1350-4177/$ - see front matter Ó 2011 Elsevier B.V. All rights reserved.
doi:10.1016/j.ultsonch.2011.05.011

126
H. Mehrabi / Ultrasonics Sonochemistry 19 (2012) 125–129
To investigate the effect of irradiation frequency on the yields of
O
O
SDS/I2/Water
u.s/25-30 oC
reactions, the model reaction was sonicated at 24 and 48 kHz with
electric power rating of 480 W. The yields of product were 84% and
82%, respectively (Table 1, Entries 7 and 12). This indicates that for
the two frequencies of ultrasound irradiation examined, there is no
difference in the reaction yield.
R'
R'
R
R
NH2OH
+
NOH
O
1 (a-j)
2 (a-j)
From the results above, the best conditions were selected as fol-
lows: oximinoketones 1 a-j (1 mmol), iodine (0.05 g, 0.2 mmol),
SDS (0.06 g, 0.2 mmol), water (15 mL), irradiation frequency
24 kHz and 25–30 °C. Under these reaction conditions, a series of
experiments for the synthesis of 1,2-diketones 2 a-j were com-
pleted with and without ultrasound respectively. The results are
summarized in Table 2.
As shown in Table 2, the synthesis of 1,2-diketones 2 a-j via
the reaction of oximinoketones 1 a-j by I2/SDS/water system
can be carried out in 80–93% yield within 30–40 min under
ultrasound irradiation, while without ultrasonic irradiation the
products were obtained in 30–57% yield within 120–160 min.
It is apparent that ultrasonic irradiation accelerates these trans-
formations.
To explore the scope and limitations of this reaction, we ex-
tended the procedure to alkyl and aryl groups. We found that the
reaction proceeded efficiently with various aryl groups to give
1,2-diketones. However, no alkyl 1,2-diketones were obtained
from reactions with alkyl groups, even under ultrasonic irradiation.
Electronic effects and the nature of substituents on the aromatic
ring did show effects in terms of reaction time under the reaction
conditions mentioned above. When aromatic aldehydes containing
electron-donating groups (such as methoxyl, or dimethylamino
group) were employed, a longer reaction time was required than
those of electron-withdrawing groups (such as halide groups) on
aromatic rings (Table 2).
Cavitation is the origin of sonochemistry. As ultrasound passes
through a liquid, the liquid can produce bubbles. These bubbles
can undergo a violent collapse, which generates very high pres-
sures and temperatures, inducing molecular fragmentation, and
highly reactive species are locally produced. In addition, ultra-
sound is known to generate extremely fine emulsions from mix-
tures of immiscible liquids to enhance mass transfer from one
phase into the other. One of the main consequences of these emul-
sions is the dramatic increase in the interfacial contact area be-
tween the reactants and an increase in the region over which
any reaction between species dissolved in the different liquids
can take place [26,27]. All of these can cause the reaction to take
place rapidly.
Scheme 1.
2.2. General procedure for the synthesis of aromatic 1,2-diketones
under ultrasound irradiation
To a magnetically stirred mixture of oximinoketone (1 mmol) in
H2O (15 mL) that was exposed to ultrasonic irradiation, iodine
(0.05 g, 0.2 mmol) and SDS (0.06 g, 0.2 mmol) were added at room
temperature for 5 min, During the sonication, the temperature of
the reaction mixture was raised to 30 °C by the addition or removal
of circulating water. The progress of the reaction was followed by
TLC (eluent: ethyl acetate/n-hexane, 4:1). The reaction went to
completion after 25–35 min. The product was extracted with
diethyl ether (2 ꢀ 15 mL), the organic layer was washed with brine
(2 ꢀ 15 mL), dried over anhydrous Na2SO4, concentrated, and puri-
fied by column chromatography on neutral alumina to afford the
pure product.
3. Results and discussion
We examined this reaction in the absence and presence of I2
and sodium dodecyl sulfate (SDS). It was found that when the reac-
tion was carried out without I2 or SDS, no reaction occurred (Table
1, Entries 1 and 2). Therefore, both of I2 and SDS are necessary for
this reaction.
To optimize the reaction conditions, the reaction of oximinoke-
tone 1a and the I2/SDS system was selected as the model reaction
at 25–30 °C under ultrasound irradiation.
To find the optimum amounts of I2/SDS, the yields of the model
reaction using various amounts of I2/SDS were obtained and com-
pared. The results were summarized in Table 1.
From these results, it can be concluded that the optimum
amounts of I2/SDS were 0.2:0.2 mol%. The desired product was ob-
tained in 84% yield within 35 min. (Table 1, Entry 7).
The effect of ultrasound irradiation on the reaction was also ob-
served. As shown in Table 1, under silent conditions by using stir-
ring for 150 min, the model reaction gave 2a in 45% yield (Table 1,
Entry 13). Under ultrasound irradiation, 2a was obtained in 84%
yield within 35 min (Table 1, Entry 7).
Regarding the mechanism of the reaction, it is proposed
that the surfactant promotes micelle formation from iodine and
the oximinoketone in water, in which the electrophilic iodine
activates hydration of the carbon–nitrogen double bond, possibly
via an iodonium ion, that suffers attack by water to form
1,2-diketone compounds and iodine in the reaction mixture
(Scheme 2).
Table 1
Effect of reaction conditions on the reaction of oximinoketone 1a and I2/SDS system
under ultrasound.
Entry Molar ratio of
Frequency
(kHz)
Time
(min)
Isolated yield
(%)
1a:I2:SDS
1
2
3
4
5
6
7
8
1:0.0:0.1
1:0.1:0.0
1:0.1:0.1
1:0.1:0.2
1:0.1:0.3
1:0.2:0.1
1:0.2:0.2
1:0.2:0.3
1:0.3:0.1
1:0.3:0.2
1:0.3:0.3
1:0.2:0.2
1:0.2:0.2
24
24
24
24
24
24
24
24
60
60
40
40
40
35
35
35
35
35
35
35
150
–
–
4. Conclusion
60
63
62
78
84
82
76
79
75
82
45
In conclusion, we have developed a facile, neutral and efficient
approach for the synthesis of aromatic 1,2-diketones from corre-
sponding oximinoketones in water under ultrasonic irradiation.
The salient features of the reaction are the following: (1) Ultrasonic
irradiation accelerates these transformations in comparison with
silent conditions. (2) Iodine is an efficient catalyst in the presence
of SDS for the cleavage of the C@N bond. (3) In this system contam-
ination by other products is avoided. (4) The workup procedure is
simple, yields are high to excellent and the reaction times are
short.
9
24
24
24
10
11
12
13
48
Stirringa
a
Yield are related to isolated pure products.

H. Mehrabi / Ultrasonics Sonochemistry 19 (2012) 125–129
127
Table 2
Synthesis of aromatic 1,2-diketones through I2/SDS/water system.
Entry
1
R
R0
Product
Yield (%)a (Time/min)b
84 (35)
Yield (%)a (Time/min)c
45 (150)
C6H5–
6-Phenanthridine
O
N
O
2a
2
p-MeC6H4–
6-Phenanthridine
81 (35)
42 (130)
O
N
O
Me
2b
3
p-FC6H4–
6-Phenanthridine
89 (30)
52 (120)
O
N
O
2c
F
4
p-ClC6H4–
6-Phenanthridine
91 (30)
50 (120)
O
N
O
O
Cl
2d
5
p-Me2NC6H4–
6-Phenanthridine
80 (40)
30 (160)
N
O
Me2N
MeO
2e
6
p-MeOC6H4–
6-Phenanthridine
90 (40)
45 (150)
O
N
O
2f
7
8
C6H5–
2-Quinoline
2-Quinoline
82 (35)
57 (130)
O
N
O
2g
p-MeC6H4–
81 (35)
51 (130)
O
N
O
Me
2h
(continued on next page)

128
H. Mehrabi / Ultrasonics Sonochemistry 19 (2012) 125–129
Table 2 (continued)
Entry
9
R
R0
Product
Yield (%)a (Time/min)b
93 (30)
Yield (%)a (Time/min)c
55 (120)
p-FC6H4–
2-Quinoline
O
N
O
2i
F
10
p-MeOC6H4–
2-Quinoline
88 (40)
48 (150)
O
N
O
2j
MeO
a
b
c
Yield are related to isolated pure products.
Reaction was performed in the presence of I2/SDS/water system under ultrasound irradiation.
Reaction was performed in the presence of I2/SDS/water system under silent conditions.
Anal. Calcd for C22H15NO2: C, 81.21; H, 4.65; N, 4.30. Found: C,
81.14; H, 4.66; N, 4.27.
O
O
R'
-
R'
NH2OH
+
R
R
O
NOH
4.1.3. 1-(4-Fluoro-phenyl)-2-phenanthridin-6-yl-ethane-1,2-dione
(2c)
+ I2
Yellow powder, M.p.158–160 °C. IR (KBr) (m
max/cmꢁ1): 3058,
O
O
1710, 1688, 1593. MS: m/z (%) = 329 (M+, 52), 301 (100), 283
(72), 178 (54), 151 (23). 1H NMR (500 MHz, CDCl3): d = 7.13 (2H,
R'
+
N
R'
I+
I I
R
R
O
3
3
H
OH
N
-
I
d, JHH = 7.4 Hz), 7.47 (1H, t, JHH = 6.8 Hz), 7.62 (1H, t,
H
O
3JHH = 6.7 Hz), 7.66 (1H, d, JHH = 7.1 Hz), 7.68 (1H, t, 3JHH = 6.7 Hz),
3
HO
+ H2O
3
3
R'
I+
I
7.73 (1H, t, JHH = 6.9 Hz), 7.76 (1H, d, JHH = 7.3 Hz), 7.82 (2H, d,
R
O
3JHH = 7.4 Hz), 8.07 (1H, d, JHH = 7.4 Hz), 9.37 (1H, d, JHH = 7.5 Hz)
ppm. 13C NMR (125 MHz, CDCl3): d = 117.8, 122.9, 124.0, 126.7,
127.8, 128.1, 128.4, 129.5, 129.8, 130.4, 130.8, 131.2, 133.8,
137.9, 148.3, 158.2, 167.8, 187.5, 194.4 ppm. Anal. Calcd for
3
3
H
N
HO
-
H
Scheme 2.
C21H12FNO2: C, 76.59; H, 3.67; N, 4.25. Found: C, 76.71; H, 3.65;
N, 4.28.
4.1. Spectral Data
4.1.1. 1-Phenanthridin-6-yl-2-phenyl-ethane-1,2-dione (2a)
4.1.4. 1-(4-Chloro-phenyl)-2-phenanthridin-6-yl-ethane-1,2-dione
(2d)
Yellow powder, M.p. 173–175 °C. IR (KBr) (m
max/cmꢁ1): 3054,
Yellow powder, M.p.167–169 °C. IR (KBr) (m
max/cmꢁ1): 3049,
1704, 1691, 1585. MS: m/z (%) = 311 (M+, 43), 283 (100), 255
(53), 178 (48), 133 (28). 1H NMR (500 MHz, CDCl3): d = 7.39 (1H,
1708, 1694, 1582. MS: m/z (%) = 345 (M+, 29), 317 (100), 289
(51), 178 (47), 167 (37). 1H NMR (500 MHz, CDCl3): d = 7.45 (1H,
3
3
t, JHH = 6.9 Hz), 7.42 (2H, t, JHH = 7.1 Hz), 7.57 (1H, t,
3
3
t, JHH = 6.9 Hz), 7.48 (2H, d, JHH = 7.6 Hz), 7.61 (1H, t,
3JHH = 6.8 Hz), 7.65 (1H, t, 3JHH = 6.8 Hz), 7.67 (1H, d, 3JHH = 7.4 Hz),
3JHH = 6.8 Hz), 7.65 (1H, d, 3JHH = 7.2 Hz), 7.69 (1H, t, JHH = 7.0 Hz),
3
3
3
7.70 (1H, t, JHH = 7.1 Hz), 7.75 (1H, t, JHH = 7.0 Hz), 7.79 (1H, d,
3JHH = 7.5 Hz), 7.88 (2H, d, 3JHH = 7.4 Hz), 8.10 (1H, d, 3JHH = 7.4 Hz),
3
3
7.71 (2H, d, JHH = 7.6 Hz), 7.74 (1H, t, JHH = 7.1 Hz), 7.79 (1H, d,
3JHH = 7.3 Hz), 8.06 (1H, d, JHH = 7.3 Hz), 9.38 (1H, d, JHH = 7.2 Hz)
ppm. 13C NMR (125 MHz, CDCl3): d = 123.6, 125.1, 127.4, 128.2,
128.5, 128.6, 129.5, 130.5, 130.6, 130.7, 131.9, 135.4, 136.7,
138.5, 142.3, 148.0, 157.7, 186.5, 195.2 ppm. Anal. Calcd for
3
3
9.32 (1H, d, JHH = 7.5 Hz) ppm. 13C NMR (125 MHz, CDCl3):
3
d = 122.5, 125.2, 126.3, 127.5, 127.7, 128.4, 129.1, 129.7, 130.1,
130.5, 132.8, 135.7, 136.3, 138.5, 147.2, 159.6, 189.2, 193.9 ppm.
Anal. Calcd for C21H13NO2: C, 81.01; H, 4.21; N, 4.50. Found: C,
80.89; H, 4.24; N, 4.55.
C21H12ClNO2: C, 72.94; H, 3.50; N, 4.05. Found: C, 72.91; H, 3.54;
N, 4.00.
4.1.5. 1-(4-Dimethylamino-phenyl)-2-phenanthridin-6-yl-ethane-1,2-
dione (2e)
4.1.2. 1-Phenanthridin-6-yl-2-p-tolyl-ethane-1,2-dione (2b)
Yellow powder, M.p. 190–192 °C. IR (KBr) (
m
max/cmꢁ1): 3036,
Yellow powder, M.p.199–200 °C. IR (KBr) (m
max/cmꢁ1): 3068,
1701, 1695, 1593. MS: m/z (%) = 325 (M+, 27), 297 (100), 272
(55), 178 (33), 147 (15). 1H NMR (500 MHz, CDCl3): d = 2.41 (3H,
1698, 1687, 1595. MS: m/z (%) = 354 (M+, 25), 326 (52), 298 (33),
178 (100), 176 (19). 1H NMR (500 MHz, CDCl3): d = 2.82 (6H, s),
3
3
3
3
s), 7.22 (2H, d, JHH = 7.6 Hz), 7.40 (1H, t, JHH = 6.9 Hz), 7.58 (1H,
6.75 (2H, d, JHH = 7.6 Hz), 7.49 (1H, t, JHH = 6.9 Hz), 7.58 (1H, t,
3
3
t, JHH = 6.8 Hz), 7.63 (1H, d, JHH = 7.2 Hz), 7.71 (2H, d,
3JHH = 6.8 Hz), 7.67 (2H, d, 3JHH = 7.6 Hz), 7.70 (1H, d, 3JHH = 7.3 Hz),
3
3
3
3
3JHH = 7.6 Hz), 7.73 (1H, t, JHH = 6.8 Hz), 7.78 (1H, t, JHH = 6.7 Hz),
7.72 (1H, t, JHH = 7.0 Hz), 7.74 (1H, t, JHH = 6.9 Hz), 7.81 (1H, d,
3
3
3
3
7.80 (1H, d, JHH = 7.3 Hz), 8.01 (1H, d, JHH = 7.3 Hz), 9.36 (1H, d,
3JHH = 7.4 Hz) ppm. 13C NMR (125 MHz, CDCl3): d = 25.7, 122.8,
123.7, 126.5, 127.8, 128.1, 128.5, 129.4, 129.7, 129.9, 130.3,
130.4, 130.8, 134.6, 137.0, 144.6, 148.1, 158.8, 187.6, 195.2 ppm.
3JHH = 7.4 Hz), 8.03 (1H, d, JHH = 7.4 Hz), 9.37 (1H, d, JHH = 7.5 Hz)
ppm. 13C NMR (125 MHz, CDCl3): d = 39.7, 113.6, 123.8, 124.7,
126.2, 127.0, 127.2, 127.3, 128.2, 129.5, 130.2, 130.5, 130.7,
131.4, 137.5, 148.3, 155.0, 157.4, 186.5, 193.6 ppm. Anal. Calcd

H. Mehrabi / Ultrasonics Sonochemistry 19 (2012) 125–129
129
for C23H18N2O2: C, 77.95; H, 5.12; N, 7.90. Found: C, 78.07; H, 5.09;
N, 7.86.
C17H10FNO2: C, 73.11; H, 3.61; N, 5.02. Found: C, 72.97; H, 3.67;
N, 5.04.
4.1.10. 1-(4- Methoxy -phenyl)-2-quinolin-2-yl-ethane-1,2-dione (2j)
4.1.6. 1-(4-Methoxy-phenyl)-2-phenanthridin-6-yl-ethane-1,2-dione
(2f)
Pale yellow powder, M.p.177–179 °C. IR (KBr) (m
max/cmꢁ1):
3062, 1708, 1690, 1594. MS: m/z (%) = 291 (M+, 36), 263 (100),
235 (35), 128 (53), 163 (14). 1H NMR (500 MHz, CDCl3): d = 3.69
Yellow powder, M.p.153–155 °C. IR (KBr) (m
max/cmꢁ1): 3045,
1703, 1695, 1580. MS: m/z (%) = 341 (M+, 43), 313 (100), 285
(22), 178 (48), 163 (17). 1H NMR (500 MHz, CDCl3): d = 3.76 (3H,
3
3
(3H, s), 6.98 (2H, d, JHH = 7.7 Hz), 7.44 (1H, t, JHH = 6.8 Hz), 7.59
3
3
3
3
(1H, t, JHH = 6.8 Hz), 7.71 (1H, d, JHH = 7.0 Hz), 7.72 (2H, d,
s), 6.98 (2H, d, JHH = 7.6 Hz), 7.44 (1H, t, JHH = 6.8 Hz), 7.58 (1H,
3JHH = 7.7 Hz), 8.07 (1H, d, 3JHH = 7.2 Hz), 8.17 (1H, d, 3JHH = 7.3 Hz),
3
3
t, JHH = 6.7 Hz), 7.68 (2H, d, JHH = 7.6 Hz), 7.69 (1H, d,
8.39 (1H, d, JHH = 7.3 Hz) ppm. 13C NMR (125 MHz, CDCl3):
3
3JHH = 7.1 Hz), 7.70 (1H, t, JHH = 6.9 Hz), 7.75 (1H, t, JHH = 6.8 Hz),
3
3
3
3
d = 60.4, 115.7, 119.8, 127.2, 128.3, 129.4, 130.1, 130.5, 130.7,
131.6, 136.3, 149.2, 157.9, 166.2, 187.4, 195.3 ppm. Anal. Calcd
for C18H13NO3: C, 74.22; H, 4.50; N, 4.81. Found: C, 74.71; H,
4.47; N, 4.70.
7.77 (1H, d, JHH = 7.3 Hz), 8.07 (1H, d, JHH = 7.3 Hz), 9.38 (1H, d,
3JHH = 7.5 Hz) ppm. 13C NMR (125 MHz, CDCl3): d = 56.3, 115.7,
123.1, 124.2, 126.6, 127.1, 127.5, 128.6, 129.4, 130.0, 130.1,
130.4, 130.8, 137.8, 148.5, 147.2, 158.2, 166.8, 186.5, 195.3 ppm.
Anal. Calcd for C22H15NO3: C, 77.41; H, 4.43; N, 4.10. Found: C,
77.29; H, 4.44; N, 4.13.
Acknowledgment
We are thankful to the Office of Graduate Studies of the Vali-e-
Asr University of Rafsanjan for the financial support.
4.1.7. 1-Phenyl-2-quinolin-2-yl-ethane-1,2-dione (2g)
Pale yellow powder, M.p.140–143 °C. IR (KBr) (m
max/cmꢁ1):
3038, 1697, 1688, 1592. MS: m/z (%) = 261 (M+, 57), 233 (100),
205 (28), 128 (67), 133 (34). 1H NMR (500 MHz, CDCl3): d = 7.40
References
3
3
(1H, t, JHH = 7.0 Hz), 7.47 (2H, t, JHH = 7.2 Hz), 7.52 (1H, t,
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7305.
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7603.
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(1997) 653.
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[17] J.M. Aizpurua, C. Palomo, Tetrahedron Lett. 24 (1983) 4367.
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[19] A. Khazaei, A.A. Manash, Synthesis (2004) 1739.
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[21] C.J. Li, Chem. Rev. 105 (2005) 3095.
3JHH = 7.1 Hz), 7.65 (1H, t, 3JHH = 6.9 Hz), 7.69 (1H, d, 3JHH = 7.3 Hz),
3
3
7.84 (2H, d, JHH = 7.5 Hz), 8.02 (1H, d, JHH = 7.4 Hz), 8.26 (1H, d,
3JHH = 7.4 Hz), 8.41 (1H, d, JHH = 7.4 Hz) ppm. 13C NMR (125 MHz,
3
CDCl3): d = 119.1, 127.1, 127.4, 129.0, 129.2, 129.7, 130.4, 130.7,
135.2, 136.5, 138.3, 149.2, 159.6, 187.7, 194.9 ppm. Anal. Calcd
for C17H11NO2: C, 78.15; H, 4.24; N, 5.36. Found: C, 78.17; H,
4.29; N, 5.33.
4.1.8. 1-Quinolin-2-yl-2-p-tolyl-ethane-1,2-dione (2h)
Pale yellow powder, M.p.165–167 °C. IR (KBr) (m
max/cmꢁ1):
3056, 1710, 1694, 1585. MS: m/z (%) = 275 (M+, 46), 247 (53),
219 (19), 128 (100), 147 (24). 1H NMR (500 MHz, CDCl3): d =
3
3
2.32 (3H, s), 7.28 (2H, d, JHH = 7.5 Hz), 7.47 (1H, t, JHH = 6.9 Hz),
3
3
7.58 (1H, t, JHH = 6.8 Hz), 7.67 (1H, d, JHH = 7.2 Hz), 7.71 (2H, d,
3JHH = 7.5 Hz), 8.07 (1H, d, 3JHH = 7.3 Hz), 8.22 (1H, d, 3JHH = 7.4 Hz),
3
8.40 (1H, d, JHH = 7.4 Hz) ppm. d = 13C NMR (125 MHz, CDCl3):
d = 23.5, 119.2, 127.0, 127.4, 129.1, 129.4, 129.5, 130.7, 130.9,
134.5, 135.2, 137.1, 148.9, 159.2, 188.2, 193.6 ppm. Anal. Calcd
for C18H13NO2: C, 78.53; H, 4.76; N, 5.09. Found: C, 78.32; H,
4.84; N, 5.14.
4.1.9. 1-(4-Fluoro-phenyl)-2-quinolin-2-yl-ethane-1,2-dione (2i)
[22] J.T. Li, M.X. Sun, Aust. J. Chem. 62 (2009) 353.
Pale yellow powder, M.p.160–162 °C. IR (KBr) (m
max/cmꢁ1):
[23] K.S. Suslick (Ed.), Ultrasound, Verlag Chemie, New York, 1988.
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Spectrum, New York and Heidelberg, (1997) p. 317.
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[26] J. Lindley, P.J. Lorimer, T.J. Mason, Ultrasonics 24 (1986) 292.
[27] R. Cella, H.A. Stefani, Tetrahedron 65 (2009) 2619.
[28] P. Gogoi, P. Hazarika, D. Konwar, J. Org. Chem. 70 (2005) 1934.
[29] H. Mehrabi, H. Loghmani-Khouzani, M.M. Sadeghi, J. Chem. Res. November
(2006) 705.
3050, 1707, 1684, 1583. MS: m/z (%) = 279 (M+, 17), 251 (100),
223 (41), 128 (82), 151 (20). 1H NMR (500 MHz, CDCl3): d = 7.13
3
3
(2H, d, JHH = 7.6 Hz), 7.40 (1H, t, JHH = 6.9 Hz), 7.62 (1H, t,
3JHH = 6.8 Hz), 7.70 (1H, d, 3JHH = 7.0 Hz), 7.81 (2H, d, 3JHH = 7.6 Hz),
3
3
8.04 (1H, d, JHH = 7.1 Hz), 8.21 (1H, d, JHH = 7.3 Hz), 8.39
3
(1H, d, JHH = 7.3 Hz) ppm. d = 13C NMR (125 MHz, CDCl3):
d = 115.6, 119.2, 127.0, 128.3, 129.1, 130.7, 130.9, 131.3, 133.5,
137.2, 148.0, 158.6, 167.8, 187.6, 194.7 ppm. Anal. Calcd for
[30] J. Safari, M. Adib, F. Sheibani, Z. Sadeghi, Turk. J. Chem. 30 (2006) 673.
[31] H. Mehrabi, Ultrason. Sonochem. 15 (2008) 279.