A green method for the electroorganic synthesis of new 1,3-indandione derivatives

Article abstract of DOI:10.1248/cpb.54.1391

This is an environmentally friendly method in the field of electroorganic reactions under controlled potential electrolysis, without toxic reagents at a carbon electrode in an undivided cell which involves the (EC) mechanism reaction and comprises two ste

Full text of DOI:10.1248/cpb.54.1391

October 2006
Chem. Pharm. Bull. 54(10) 1391—1396 (2006)
1391
A Green Method for the Electroorganic Synthesis of New 1,3-Indandione
Derivatives
Abdolmajid Bayandori MOGHADDAM, Mohammad Reza GANJALI,* Parviz NOROUZI, and
Maryam LATIFI
Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran; P. O. Box 14155–6455, Tehran, Iran.
Received May 22, 2006; accepted July 11, 2006
This is an environmentally friendly method in the field of electroorganic reactions under controlled potential
electrolysis, without toxic reagents at a carbon electrode in an undivided cell which involves the (EC) mechanism
reaction and comprises two steps alternatively; (i) electrochemical oxidation and (ii) chemical reaction. In partic-
ular, the electrochemical oxidation of 4-tert-butylcatechol, 4-methylcatechol and 2,3-dihydroxybenzoic acid in the
presence of 2-phenyl-1,3-indandione has been studied in a water–acetonitrile (90 : 10) mixture. The research in-
cludes the use of a variety of experimental techniques, such as cyclic voltammetry, controlled-potential electroly-
1
sis, and spectroscopic identification of products (FT-IR, H-NMR, and MS spectrometry).
Key words electro-organic reaction; ortho-dihydroxybenzene; quasi-reversible process; (EC) mechanism; 2-phenyl-1,3-indan-
dione
1,3-Indandione derivatives present anticoagulant proper- o-quinone-4-tert-butyl (2a) and vice versa within a quasi-
ties and the synthesis and pharmacological properties of 1,3- reversible two-electron and two-proton process (DEpꢀ
1—6)
23,24)
A1 C1
indandione derivatives have been investigated.
0.186 V).
A peak current ratio (I /I ) of nearly unity,
P P
On the other hand, it has been reported that ortho- and particularly during the repetitive potential recycle, can be
para-hydroquinones and their quinone derivatives are abun- considered as a criterion for the stability of o-quinone pro-
dant in nature and play important roles in many biological duced on the electrode surface under the experimental condi-
7
—11)
25,26)
systems.
In addition, many chemicals of this category tions. In other words, any hydroxylation
or dimeriza-
reactions are too slow to be observed on the time
auto-oxidation via the radical formation inhibition. These scale of the cyclic voltammetry.
compounds exhibit a wide variety of physiological and phar- The oxidation of 4-tert-butylcatechol (1a) in the presence
2
7,28)
demonstrate an antioxidant activity and are able to prevent tion
12)
13)
29)
macological properties. They participate in normal cell of 2-phenyl-1,3-indandione (3) (pK ꢀ4.1) as a nucleophile
a
functions such as neurotransmitters. Furthermore, natural was studied in detail. Figure 1, CV b presents the cyclic
pyrocatechols extracted from plants (catechins and other voltammogram obtained for a 0.25 mM solution of 1a in the
polyphenols from green tea) have been found to illustrate an- presence of 0.25 mM 3. The corresponding voltammogram
14)
ticancer properties.
exhibits one anodic peak at 0.364 V (A ) vs. the reference
1
For these reasons, knowledge of the redox properties of electrode, where the cathodic counterpart of the anodic peak
these compounds is important for a better understanding of A1 decreases. In this condition, the positive shift of the A1
their behavior in biological environments. Redox properties peak in the presence of 2-phenyl-1,3-indandione (3) (from
of some derivatives of these compounds in aqueous solutions 0.291 V in CV a to 0.364 V in CV b) is attributed to the thin
1
5—22)
is documented.
We thought that synthesis of a new 1,3-indandione deriva- insulating it.
tives with both structures of 1,3-indandione and hydro- It is seen that proportionally to the augmentation of the po-
film formation of the product (5a) on the electrode surface,
15)
quinone would be useful from the point of view of pharma- tential sweep rate, the height of C peak increases (Fig. 2). A
1
ceutical properties. This idea prompted us to development of similar situation is observed when the concentration ratio of
a facile and environmentally friendly reagentless electro- 2-phenyl-1,3-indandione (3) to 1a decreased. A plot of the
C1 A1
chemical method for the synthesis of some new 1,3-indan- peak current ratio (IP /IP ) vs. the scan rate confirms the re-
dione derivatives in aqueous solutions with high atomic activity of o-quinones (2a) towards 3, appearing as an in-
economy under ambient conditions and in an undivided cell crease in the height of the cathodic peak C at higher scan
1
using a graphite electrode and delineates the application of rates (Fig. 2, curve I).
electrochemical studies in the design of an electrochemical
method for the synthesis of new 1,3-indandione derivatives mination of the number of transferred electrons in aqueous
5a—c). solution, containing 0.25 mmol of 1a and 0.25 mmol of 3 at
Electroorganic Reactions of 4-tert-Butylcatechol (1a) 0.25 V vs. the RE. It is illustrated that proportionally to the
Controlled-potential coulometry was performed for deter-
(
and 4-Methylcatechol (1b) Figure 1, CV a displays the advancement of coulometry, all anodic and cathodic peaks
typical successive cyclic voltammogram (CV) of 0.25 mM 4- decrease and disappear when the charge consumption be-
ꢁ
tert-butylcatechol (1a) in aqueous media (H O : AN, 90 : 10), comes about 2e per molecule of 1a.
2
containing phosphate buffer (pHꢀ7.0, cꢀ0.15 M). This figure
A cyclic voltammogram (CV) of 0.25 mM 4-methylcate-
demonstrates one anodic peak (A ) (at 0.291 V) and one cor- chol (1b) in aqueous solution (H O : AN, 90 : 10) shows one
1
2
responding cathodic peak (C ) (at 0.105 V), which corre- anodic (A at 0.335 V) and the corresponding cathodic peak
1
1
sponds to the transformation of 4-tert-butylcatechol (1a) to (C at 0.023 V) which correspond to the 4-methylcatechol
1
∗
To whom correspondence should be addressed. e-mail: Ganjali@khayam.ut.ac.ir
© 2006 Pharmaceutical Society of Japan

1
392
Vol. 54, No. 10
Chart 1
intermediate 4b. In this figure, voltammogram a is related to
the electrochemical oxidation of 2-phenyl-1,3-indandione
with an irreversible oxidation peak. Controlled-potential
coulometry for determination the number of transferred
electrons was performed in aqueous solution containing
0
.125 mmol of 1b and 0.125 mmol of 3 at 0.30 V vs. RE. It
ꢁ
shown that consumption about 2e per molecule of 1b.
Electroorganic Reactions of 2,3-Dihydroxybenzoic Acid
(
1c) Figure 4, CV a displays the typical successive cyclic
voltammogram (CV) of 0.25 mM 2,3-dihydroxybenzoic acid
1c) in aqueous solution (H O : AN, 90 : 10), containing
(
2
phosphate buffer (pHꢀ7.0, cꢀ0.15 M). This CV demon-
strates one anodic peak (A ) (at 0.441 V) and one correspon-
2
ding cathodic peak (C ) (at 0.012 V), which corresponds to
2
the transformation of 2,3-dihydroxybenzoic acid (1c) to o-
Fig. 1. Comparative Cyclic Voltammograms of 0.25 mM 4-tert-Butylcate- quinone-3-carboxilic acid (2c) and vice versa within a quasi-
chol without (a) and with (b) 2-Phenyl-1,3-indandione, at a Glassy-Carbon
reversible two-electron and two-proton process (DEpꢀ
2
Electrode (Sꢀp mm ) in Aqueous Solution (H O : AN, 90 : 10) Containing
23,24)
2
0
.429 V).
of Phosphate Buffer (pHꢀ7.0, cꢀ0.15 M)
ꢁ1
CV b presents the cyclic voltammogram obtained for a
Scan rate: 150 mV·s
.
0
.25 mM solution of 1a in the presence of 0.25 mM 3. The
corresponding voltammogram exhibits two anodic peaks at
1b)/o-quinone-4-methyl (2b) couple within a quasi-re- 0.214 V (A ) and 0.501 V (A ) vs. the reference electrode,
(
1
2
versible two-electron and two-proton process (Fig. 3, CV b). where the cathodic counterpart of the anodic peak A de-
2
Figure 3, c and d shows the cyclic voltammograms (CVs) of creases. In this condition, a first irreversible peak A (Fig. 4,
1
0
.25 mM 1b in the presence of 0.25 mM 3, the voltammogram CVs b and c) is related to the electrochemical oxidation of 2-
exhibits cathodic counterpart of the anodic peak A decreases phenyl-1,3-indandione (3). The positive shift of the A peak
1
2
and a new cathodic peak C is related to electroreduction of in the presence of 2-phenyl-1,3-indandione (3) (from 0.441 V
0

October 2006
1393
Fig. 2. Typical Cyclic Voltammograms of 0.25 mM 4-tert-Butylcatechol in the Presence of 0.25 mM 2-Phenyl-1,3-indandione, at a Glassy-Carbon Electrode
2
(
Sꢀp mm ) in Aqueous Solution (H O : AN, 90 : 10) Containing of Phosphate Buffer (pHꢀ7.0, cꢀ0.15 M) in Different Scan Rates
(
2
C1 A1
I) Variation of the peak current ratio (IP /IP ) versus scan rate.
Fig. 3. Comparative Cyclic Voltammograms of 0.25 mM 4-Methylcatechol without (b) and with (c and d) 2-Phenyl-1,3-indandione, (a) Cyclic Voltammo-
2
gram of 0.25 mM 2-Phenyl-1,3-indandione, at a Glassy-Carbon Electrode (Sꢀp mm ) in Aqueous Solution (H O : AN, 90 : 10) Containing of Phosphate
2
Buffer (pHꢀ7.0, cꢀ0.15 M)
ꢁ1
ꢁ1
Scan rates: a, b, c at 250 mV·s and d at 500 mV·s
.
Fig. 4. Comparative Cyclic Voltammograms of 0.25 mM 2,3-Dihydroxy-
benzoic Acid without (a) and with (b) 2-Phenyl-1,3-indandione, (c) Cyclic
Fig. 5. Continuous Cyclic Voltammograms of 0.25 mM 2,3-Dihydroxyben-
zoic Acid in the Presence of 0.25 mM 2-Phenyl-1,3-indandione, at a Glassy-
2
Voltammogram of 0.25 mM 2-Phenyl-1,3-indandione, at a Glassy-Carbon
Carbon Electrode (Sꢀp mm ) in Aqueous Solution (H O : AN, 90 : 10) Con-
2
2
Electrode (Sꢀp mm ) in Aqueous Solution (H O : AN, 90 : 10) Containing
taining of Phosphate Buffer (pHꢀ7.0, cꢀ0.15 M)
2
of Phosphate Buffer (pHꢀ7.0, cꢀ0.15 M)
Scan rate: 250 mV·sꢁ1
.
ꢁ1
Scan rate: 500 mV·s
.

1
394
Vol. 54, No. 10
Fig. 6. Typical Cyclic Voltammograms of 0.25 mM 2,3-Dihydroxybenzoic Acid in the Presence of 0.25 mM 2-Phenyl-1,3-indandione, at a Glassy-Carbon
2
Electrode (Sꢀp mm ) in Aqueous Solution (H O : AN, 90 : 10) Containing of Phosphate Buffer (pHꢀ7.0, cꢀ0.15 M) in Different Scan Rates
(
2
A2 1/2
1/2
ꢁ1/2
C2 A2
I) Variation of the peak current function (IP /n ) (mA s mV ) versus scan rate. (II) Variation of the peak current ratio (IP /IP ) versus scan rate.
Fig. 7. Cyclic Voltammograms of 5b at a Glassy Carbon Electrode
Fig. 8. Cyclic Voltammograms of 5c at a Glassy Carbon Electrode
2
2
(
Sꢀp mm ) in 0.05 M LiClO –AN
(Sꢀp mm ) in 0.05 M LiClO –AN
4
4
in CV a to 0.501 V in CV b) is attributed to the thin film for- in the activity of respective o-quinone toward the side reac-
mation of the product (5c) on the electrode surface, insulat- tions such as polymerization reaction. In spite of the fact that
15)
ing it. This can be inferred from Fig. 5 during the course of the rate of polymerization reaction increases with augmenta-
continuous cyclic voltammograms. tion of pH, because the needs to the formation of enolate
It is seen that proportionally to the augmentation of the po- anion from 2-phenyl-1,3-indandione through acid dissocia-
tential sweep rate, the height of C peak increases (Fig. 6). A tion reaction, electrochemical synthesis of 5a—c was carried
2
similar situation is observed when the concentration ratio of out in pHꢀ7.0.
2-phenyl-1,3-indandione (3) to 1a decreased. In this figure,
At the end of this section, a brief discussion about the an-
anodic peak A corresponds to the oxidation of 2-phenyl-1,3- odic oxidation of 2-phenyl-1,3-indandione (3) during the
1
indandione (3). The current function for the A peak electrolysis progress seems to be interesting. It should be
2
A2 1/2
(
IP /v ) changes only slightly with the scan rate increase taken into consideration that although 2-phenyl-1,3-indan-
(
Fig. 3, curve I). In fact, such behaviour is indicative of an dione (3) has an oxidation peak in 0.214 V (Fig. 4, CV c), the
30,31)
EC mechanism.
On the other hand, a plot of the peak oxidation of 1a—c were more intensive than the oxidation of
C2 A2
current ratio (IP /IP ) vs. the scan rate confirms the reactiv- 3 and circumvent during the preparative reaction, which the
ity of o-quinones (2a) towards 3, appearing as an increase in resultants led to the new 1,3-indandione derivatives forma-
the height of the cathodic peak C at higher scan rates (Fig. tion as final products (5a—c). The cause of this phenomenon
2
3, curve II).
is the greater anodic current of 1c (Fig. 4, CV a) in compari-
Controlled-potential coulometry for determination the son with that of 3 (Fig. 4, CV c) for the same concentration
number of transferred electrons was performed in aqueous and scan rate in the comparative cyclic voltammograms. The
solution containing 0.125 mmol of 1c and 0.125 mmol of 3 at oxidation form of 3 does not present any reaction with the
ꢁ
0
.40 V vs. RE. It shown that consumption about 2e per mol- electrochemically generated o-quinones. The oxidation of 3
ecule of 1c.
decreases the yield of products in the preparative reaction.
The existence of –COOH group with electron-withdraw-
Finally, we obtained the cyclic voltammograms of 5b and
ing character at molecular ring (1c) causes an augmentation 5c at glassy carbon electrode in acetonitrile solution that in-

October 2006
1395
Table 1. Electroanalytical and Preparative Data
Peak potentials (V)
Conversion
Applied potential Purification
Product
A1
A2
C1
C2
C0
yield (%)
1a→5a
1b→5b
1c→5c
0.364
0.411
0.214
—
—
0.501
0.026
0.046
—
—
—
ꢁ0.010
—
0.095
—
0.250 V
0.300 V
0.400 V
H O : AN
52
77
61
2
H O : AN
2
H O : AN
2
KBr
max
(
100), 273 (10), 255 (10), 165 (25), 110 (20), 76 (15), 44 (25). FT-IR n
volves a transfer of two electrons and two protons to provide
the associated hydroquinones (Figs. 7, 8).
ꢁ1
cm : 3475 (OH, br), 3300—2003 (OH, br, carboxylic acid), 1741 (CꢀO),
699 (CꢀO), 1618, 1595, 1444 (Ar), 1380, 1340, 1236 (C–O), 925, 771,
96. H-NMR (DMSO-d , 500 MHz) d: 5.44 (1H, s, catechol ring proton),
.46 (1H, s, catechol ring proton), 7.26—7.30 (5H, m, Ar protons), 7.69—
.74 (4H, m, Ar protons), 7.94 (1H, s, hydroxy proton), 8.21 (1H, s, hydroxy
1
6
6
7
1
6
Experimental
Apparatus All of the electrochemical experiments were performed with
the aid of a setup, comprising a PC PIII Pentium 300 MHz microcomputer
equipped with a data acquisition board (PCL-818PG, PC-Labcard Co.) and a
proton), 17.61 (1H, br, carboxilic acid proton).
32)
custom made potentiostat. The working electrode (WE) used in the
Acknowledgements The financial support provided by the Tehran Uni-
2
voltammetry experiment was a glassy carbon electrode (disc, Sꢀp mm ). A
versity Research Affairs is gratefully acknowledged by the authors.
platinum wire was used as the counter electrode (CE). Moreover, the used
WE in controlled-potential coulometry was a carbon rod (4 mm in diameter References
and 3 cm in length). In addition, the macroscale electrolysis was an assembly
of three carbon rods (8 mm in diameter and 4 cm in length). The WE poten-
tials were measured versus the Ag|AgCl|KCl, sat. as a reference electrode.
The cyclic voltammograms of 5b and 5c obtained in acetonitrile (AN) con-
1) Link K. P., Circulation, 19, 97—107 (1959).
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taining 0.05 M LiClO as a supporting electrolyte and the working electrode
4
ꢂ
(
WE) potentials were measured versus the Ag|0.01 M Ag couple in the elec-
trolyte solution as a reference electrode.
Also, the NMR spectra were recorded on a Bruker FT-NMR-80 AC, the
IR spectra were recorded on a Shimadzu FT-IR-4300 Spectrophotometer.
MS spectra were obtained using a HP (Agilent Technology) GC-6890, MS-
6) Beauregard J. R., Tusing T. W., Hanzal R. F., J. Agric. Food Chem., 3,
124—127 (1955).
5
973 (EI at 20 eV and 70 eV). The melting point of the products were ob-
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tained with the use of an electrothermal melting point model 9200.
Reagents Furthermore, 4-tert-butylcatechol, were reagent-grade mate-
rial and phosphate salts was of pro-analysis grade from Merck. In addition,
2-phenyl-1,3-indandione, 4-methylcatechol and 2,3-dihydroxybenzoic acid
were reagent-grade materials from Aldrich and LiClO , AgNO and HPLC-
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4
3
grade acetonitrile (Fluka) were used as received. These chemicals were used
without further purification. All experiments were carried out at room tem-
perature.
Electroorganic Synthesis of Products (5a—c) In a typical procedure,
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1
(
00 ml mixture of water–acetonitrile (90 : 10) containing of phosphate buffer
pHꢀ7.0, cꢀ0.15 M) was pre-electrolyzed at the chosen potential (Table 1),
in an undivided cell; subsequently, 2 mmol of 4-tert-butylcatechol (1a), 4-
methylcatechol (1b) or 2,3-dihydroxybenzoic acid (1c), and 2-phenyl-1,3-in- 13) Antonio L., Grillasca J., Taskinen J., Elovaara E., Burchell B., Piet M.,
dandione (3) (2 mmol) were added to the cell. The electrolysis was stopped
when the current reached a value that was less than 5% of the initial value.
Ethell B., Ouzzine M., Fournel S., Magdalou J., Drug Metab. Dispos.,
30, 199—207 (2002).
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carbon anode was washed in acetone in order to reactivate it. At the end of 15) Bayandori Moghaddam A., Kobarfard F., Fakhari A. R., Nematollahi
electrolysis, the precipitated solid was collected by filtration and purification
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2
1
acterized by using FT-IR, H-NMR, and MS.
(1987).
Products Characteristics 2-(2-tert-Butyl-4,5-dihydroxyphenyl)-2-
phenyl-2H-indene-1,3-dione (C H O , 5a): mp >205 °C. MS (70 eV):
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161—166 (2006).
2
5
22
4
ꢂ
ꢂ
ꢂ
m/zꢀ387 [Mꢂ1] (20), 386 [M] (90), 371 [MꢁCH ] (100), 235 (5), 221
3
KBr
ꢁ1
(
5), 165 (15), 105 (20), 77 (10). FT-IR nmax cm : 3463 (OH, br), 3058
3
(C–H, sp ), 1737 (CꢀO), 1695 (CꢀO), 1596, 1521 (Ar), 1441, 1429 (tert),
1
1
1
307, 1263, 1213 (C–O), 1039, 698. H-NMR (DMSO-d , 500 MHz) d:
6
.18 (9H, s, tert-butyl), 5.88 (1H, s, catechol ring proton), 6.15 (1H, s, cate-
chol ring proton), 7.35—7.41 (5H, m, Ar protons), 7.97—7.99 (4H, m, Ar
protons), 8.02 (1H, s, hydroxy proton), 8.07 (1H, s, hydroxy proton).
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2
-(4,5-Dihydroxyphenyl-2-methylphenyl)-2-phenyl-2H-indene-1,3-dione
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New York, 2001, p. 31.
ꢂ
ꢂ
(
(
C H O , 5b): mp >205 °C. MS (70 eV): m/zꢀ345 [Mꢂ1] (20), 344 [M]
22
16
4
KBr
max
100), 308 (15), 239 (15), 221 (10), 165 (20), 105 (10), 76 (20). FT-IR n
ꢁ
1
cm : 3490 (OH, br), 3367 (OH, br), 1741 (CꢀO), 1699 (CꢀO), 1606,
1
1
5
516 (Ar), 1361, 1290, 1255, 1051 (C–O), 771, 611. H-NMR (DMSO-d ,
6
00 MHz) d: 1.67 (3H, s, Me), 6.04 (1H, s, catechol ring proton); 6.51 (1H,
s, catechol ring proton); 7.24—7.41 (5H, m, Ar protons); 8.01—8.07 (4H,
m, Ar protons), 8.64 (1H, s, hydroxy proton), 8.87 (1H, s, hydroxy proton).
5
-(2,3-Dihydro-1,3-dioxo-2-phenyl-1H-inden-2-yl)-2,3-dihydroxybenzoic 25) Young T. E., Griswold J. R., Hulbert M. H., J. Org. Chem., 39, 1980—
ꢂ
Acid (C H O , 5c): mp ꢃ205 °C. MS (20, 70 eV): m/zꢀ330 [MꢁCO ]
1982 (1974).
22
14
6
2

1
396
Vol. 54, No. 10
2
2
2
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