Efficient synthesis of chalcones at room temperature in the presence of potassium phosphate

Full text of DOI:10.1134/S107042800707024X

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2007, Vol. 43, No. 7, pp. 1088–1089. © Pleiades Publishing, Ltd., 2007.
Published in Russian in Zhurnal Organicheskoi Khimii, 2007, Vol. 43, No. 7, pp. 1093–1094.
SHORT
COMMUNICATIONS
Efficient Synthesis of Chalcones at Room Temperature
in the Presence of Potassium Phosphate*
a
a
a
b
D. M. Pore , Uday V. Desai , T. S. Thopate , and P. P. Wadgaonkar
a
Department of Chemistry, Shivaji University, Kolhapur, 416004, India
fax: +(91)2692333; e-mail: p_dattaprasad@rediffmail.com
b
Polymer Science and Engineering Division, National Chemical Laboratory, Pune, 411008, India
Received June 15, 2006
DOI: 10.1134/S107042800707024X
Chalcones (α,β-unsaturated aromatic ketones) are
important intermediate products in organic synthesis
1–5]; they also exhibit versatile biological activity [6–
0]. These compounds are usually synthesized by the
with p-bromoacetophenone was complete in 20 min to
afford 96% of the corresponding chalcone. The slowest
reaction was observed with p-chlorobenzaldehyde and
[
1
6
-methoxy-1,2,3,4-tetrahydronaphthalen-1-one: the
Claisen–Schmidt condensation of aromatic aldehydes
with methyl ketones in the presence of bases, such as
aluminum oxide [11], barium hydroxide [12], hydro-
talcite [13], zeolites [14], natural phosphate [15], etc.
yield of 2-(p-chlorobenzylidene)-6-methoxy-1,2,3,4-
tetrahydronaphthalen-1-one was 70% in 2 h.
General procedure for the synthesis of chal-
cones. Potassium phosphate, 0.327 g (1.5 mmol), was
added under stirring to a solution of 10 mmol of the
corresponding aldehyde and 10 mmol of ketone in
We previously found [16] that potassium phosphate
is capable of catalyzing nitroaldol condensation. We
presumed that it may also be active in the Claisen–
Schmidt condensation and examined reactions of aro-
matic aldehydes with substituted acetophenones in the
presence of K PO at room temperature. The reactions
1
5 ml of ethanol. The mixture was stirred at room
temperature until the reaction was complete (TLC) and
extracted with diethyl ether. The extract was repeatedly
washed with water and dried over anhydrous sodium
sulfate, the solvent was removed, and the residue was
purified by recrystallization from anhydrous ethanol.
All the isolated compounds were identified by com-
paring their spectral data with those reported in the
literature.
3
4
were carried out in ethanol using equimolar amounts of
the reactants and 15 mol % of potassium phosphate.
The target products were isolated in good to excellent
yields (see table). It is seen from the obtained results
that compounds having electron-withdrawing groups
reacted at a higher rate, and the corresponding chal-
cones were isolated in almost quantitative yield.
Furfurol turned out to be the most reactive: its reaction
U.V. Desai thanks the UGC, New Delhi, for finan-
cial assistance.
O
O
CHO
Me
K PO , EtOH
3 4
R
+
R'
R'
R
O
O
CHO
K PO , EtOH
3
4
+
Cl
MeO
MeO
Cl
For R and R′, see table.
*
The text was submitted by the authors in English.
1088

EFFICIENT SYNTHESIS OF CHALCONES
1089
Reactions of aromatic aldehydes with ketones in ethanol at room temperature in the presence of potassium phosphate
a
a
R
R′
4-Cl
Reaction time, min
Yield, %
R
R′
Reaction time, min
Yield, %
4
-MeO
55
40
30
30
90
60
90
55
94
89
94
96
86
83
71
81
4-Cl
4-Me
H
35
25
50
30
50
50
60
20
89
88
84
92
86
88
79
96
H
4-Cl
4-Cl
3
4
4
4
4
-O
-Cl
2
N
4-Cl
4-MeO
H
4-Cl
2
3-O N
H
-Me
-Cl
4-Cl
4-Me
H
4-MeO
4-MeO
4-MeO
2
3-O N
H
4-MeO
4-Me
4-Br
-MeO
H
Furfurol
a
Isolated product after purification.
REFERENCES
9. Bois, F., Boumendjel, A., Mariotte, A.M., Conseil, G.,
and DiPetro, A., Bioorg. Med. Chem., 1999, vol. 7,
p. 2691.
1
2
. Tomazela, D.M., Pupo, M.T., Passador, E.A.P., da Sil-
va, M.F.G.F., Vieira, P.C., Fernandes, J.B., Rodri-
gues, F.E., Oliva, G., and Pirani, J.R., Phytochemistry,
000, vol. 55, no. 6, p. 643.
. Wang, X.-S., Shi, D.-Q., and Tu, S.-J., Synth. Commun.,
002, vol. 32, no. 22, p. 3449.
1
1
0. Kidwai, M., Sapra, P., Misra, P., Saxena, R.K., and
Singh, M., Bioorg. Med. Chem. Lett., 2001, vol. 9, no.
2
2
, p. 217.
1. Varma, R.S., Kabalka, G.W., Evans, L.T., and Pag-
2
ni, R.M., Synth. Commun., 1985, vol. 15, no. 4, p. 279.
3
4
. Levai, A., Arkivoc, 2005, part (ix), p. 344.
. Ranu, B.C., Dey, S.S., and Samanta, S., Arkivoc, 2005,
part (iii), p. 44.
12. Sinsterra, J.V., Garcia-Raso, A., Cabello, J.A., and
Marinas, J.M., Synthesis, 1984, p. 502.
1
3. Liment, M.J., Corma, A., Iborra, S., and Primo, J.,
5
6
. Sandler, S.R., and Karo, W., Organic Functional Group
Preparations, New York: Academic, 1972, vol. 3, p. 372.
. Mukherjee, S., Kumar, V., Prasad, A.K., Raj, H.G.,
Bracke, M.E., Olsen, C.E., Jain, S.C., and Parmar, V.S.,
Bioorg. Med. Chem., 2001, vol. 9, p. 337.
. Dinkova-Kostova, A.T., Beygunawardana, C., and Tala-
lay, P., J. Med. Chem., 1998, vol. 41, no. 26, p. 5287.
. Ram, V.J., Saxena, A. S., Srivastava, S., and Chandra, S.,
Bioorg. Med. Chem. Lett., 2000, vol. 10, no. 19, p. 2159.
J. Catal., 1995, vol. 151, no. 1, p. 60.
14. Guida, A., Lhouty, D., Tichit, F., Figueras, P., and
Geneste, P., Appl Catal., A, 1997, vol. 164, p. 251.
1
1
5. Sebti, S., Solhy, A., Tahir, R., Boulaajaj, S., Mayo-
ral, J.A., Fraile, J.M., Kossir, A., and Oumimoun, H.,
Tetrahedron Lett., 2001, vol. 42, p. 7953.
6. Desai, U.V., Pore, D.M., Mane, R.B., Solabannavar, S.B.,
and Wadgaonkar, P.P., Synth. Commun., 2004, vol. 34,
p. 19.
7
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