A clean synthesis of 1-oxo-hexahydroxanthene derivatives in aqueous media catalyzed by TEBA

Article abstract of DOI:10.1081/SCC-200046510

A series of 1-oxo-1,2,3,4,9,10-hexahydroxanthene derivatives were synthesized from substituted salicylaldehydes and substituted 1,3-hexanedione in water at 90°C catalyzed by TEBA. The structure of the product was confirmed by X-ray analysis. Compared with other synthetic methods, this new method has the advantages of easier workup, milder reaction conditions, high yields (85 ～ 95%) and environmentally benign procedure.

Full text of DOI:10.1081/SCC-200046510

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A Clean Synthesis of
1‐Oxo‐hexahydroxanthene
Derivatives in Aqueous Media
Catalyzed by TEBA
a b
a c b
a b
Xiang‐shan Wang
, Da‐qing Shi
, Yu‐ling Li
c
c
c
,
a
Hong Chen , Xian‐yong Wei & Zhi‐min Zong
Department of Chemistry, Xuzhou Normal
University, Xuzhou, Jiangsu, 221116, China
b
The Key Laboratory of Biotechnology on Medical
Plant, Xuzhou, China
c
School of Chemical Engineering, China University
of Mining and Technology, Xuzhou, China
Published online: 05 Aug 2006.
To cite this article: Xiang‐shan Wang , Da‐qing Shi , Yu‐ling Li , Hong Chen , Xian‐yong
Wei & Zhi‐min Zong (2005): A Clean Synthesis of 1‐Oxo‐hexahydroxanthene Derivatives
in Aqueous Media Catalyzed by TEBA, Synthetic Communications: An International
Journal for Rapid Communication of Synthetic Organic Chemistry, 35:1, 97-104
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Synthetic Communications , 35: 97–104, 2005
Copyright # Taylor & Francis, Inc.
ISSN 0039-7911 print/1532-2432 online
DOI: 10.1081/SCC-200046510
A Clean Synthesis of 1-Oxo-
hexahydroxanthene Derivatives in Aqueous
Media Catalyzed by TEBA
Xiang-shan Wang
Department of Chemistry, Xuzhou Normal University, Xuzhou,
Jiangsu, China and School of Chemical Engineering, China University of
Mining and Technology, Xuzhou, China and The Key Laboratory of
Biotechnology on Medical Plant, Xuzhou, China
Da-qing Shi and Yu-ling Li
Department of Chemistry, Xuzhou Normal University, Xuzhou,
Jiangsu, China and The Key Laboratory of Biotechnology on
Medical Plant, Xuzhou, China
Hong Chen, Xian-yong Wei, and Zhi-min Zong
School of Chemical Engineering, China University of Mining and
Technology, Xuzhou, China
Abstract: A series of 1-oxo-1,2,3,4,9,10-hexahydroxanthene derivatives were syn-
thesized from substituted salicylaldehydes and substituted 1,3-hexanedione in water
at 908C catalyzed by TEBA. The structure of the product was confirmed by X-ray
analysis. Compared with other synthetic methods, this new method has the advantages
of easier workup, milder reaction conditions, high yields (85 ꢀ 95%) and environmen-
tally benign procedure.
Keywords: Hexahydroxanthene, salicylaldehyde, TEBA, water, synthesis
Chromene is an important class of compounds, which is found to possess anti-
[1]
estrogenic activity and is devoid of any agonistic activity, , is evaluated for
Received in Japan August 19, 2004
Address correspondence to Xiang-shan Wang, Department of Chemistry, Xuzhou
Normal University, Xuzhou, Jiangsu 221116, China. E-mail: xswang1974@yahoo.com

98
X. Wang et al.
[
2–5]
potassium channel opening and hypotensive activies,
vasodilator and
antimicrobial
activity, and biological activity of high-affinity retinoic acid receptor antag-
[
6]
[7]
antihypertensive activies, , b-adrenolytic activity,
[8]
[9]
onist. The increasing demands of environmental legislation have been
prompting the chemical industry to minimize or preferably eliminate waste
production in chemical manufacture. Environmental benign processes are
requested for primary prevention of pollution. One of the most promising
[10,11]
[12,13]
approaches is use water as reaction medium.
Breslow,
who
showed that hydrophobic effects could strongly enhance the rate of several
organic reactions, rediscovered the use of water as a solvent in organic
chemistry in 1980s. In recent years, there has been increasing recognition
that water is an attractive medium for many organic reactions, such as
[
14,15]
[16,17]
Diels-Alder reactions,
Claisen Rearrangement reactions,
Refor-
Compared with
organic solvent, water is less expensive, less dangerous, and environment-
[
18,19]
[20]
matsky reactions,
and Pinacol-coupling reactions.
[
21–24]
friendly. In our previous papers,
we have reported the Knoevenagel
condensation, Darzens condensation reaction and addition reaction in the
water successfully. Herein we would like to report a simple synthesis of
1
-oxo-1,2,3,4,9,10-hexahydroxanthene derivatives in water catalyzed by
TEBA.
An equimolar mixture of substituted salicylaldehyde, (1), and substituted
,3-hexanedione (2) in the presence of triethylbenzylammoium chloride
TEBA) as a cationic surfactant in a small amount of water was stirred at
08C for 3–5 h. The crude product was collected by filtration, washed with
1
(
9
water, and purified by recrystallization to give 1-oxo-1,2,3,4,9,10-hexahy-
droxanthene derivatives (3) in high yields (Scheme 1). The results are
summarized in Table 1.
Table 1 summarizes the results on this reaction. The products of 3 were
further purified by recrystallizing from 95% EtOH. The 1-oxo-1,2,3,4,9,10-
hexahydroanthene 3 were isolated in a practically pure form by simple
Buchner filtration of the final aqueous mixture. The reactions occur in a
Scheme 1.

Synthesis of 1-Oxo-hexahydroxanthene Derivatives
99
Table 1. The results on the reaction of substituted salicylaldehydes (1) and substi-
tuted 1,3-hexanedione (2)
Time
(h)
Yields
(%)
1
2
3
4
Entry
R
R
R
R
Mp(8C)(Lit)
244–246
3
3
3
3
3
3
3
a
b
c
d
e
f
H
H
H
H
H
H
H
H
H
H
Cl
H
H
H
H
H
H
5
4
4
3
4
4
5
86
87
88
85
90
90
91
245–247
235–236
245–246
254–256
255–257
216–218
H
Br
H
NO2
Cl
Cl
Br
H
Br
g
–CH 55 CH–
CH 55 CH–
[
25]
3
3
3
3
3
3
3
h
CH
3
H
H
H
Cl
H
H
H
H
H
H
4
4
4
3
4
4
4
92
95
92
91
90
95
94
206–208(203–205)
238–239
253–255
i
CH3
CH3
j
H
Br
NO
Cl
k
l
CH
CH
3
3
H
2
205–207
235–237
Cl
Br
H
m
n
CH3
CH
Br
260–262
245–248(241–243)
[
25]
3
–CH 55 CH–
CH 55 CH–
3
o
CH3
H
CH3
H
5
86
218–219
short time (3 ꢀ 5 h) with high yields. The structure of the product 3o was
1
confirmed by X-ray analysis , the structure of 3o is shown in Fig. 1.
In conclusion, we have reported a high-yield one-pot procedure at 908C in
water for the synthesis of 1-oxo-1,2,3,4,9,10-hexahydroanthene derivatives in
water. Compared to other methods, this new method has the advantage of good
yields, mild reaction conditions, easy workup, inexpensive reagents, and
environmentally friendly reaction conditions.
EXPERIMENTAL
Melting points were determined in open capillaries and are uncorrected. IR
1
spectra were recorded on a TENSOR 27 spectrometer in KBr. H NMR
spectra were obtained for solution in CDCl with Me Si as internal standard
3
4
1
X-ray crystallography for 3o: Empirical formula C H O , F ¼ 380.46,
2
4
28
4
W
˚
T ¼ 193(2)
K,
Orthorhombic,
space
group
Pbca,
a ¼ 15.559(3) A,
3
˚
˚
˚
b ¼ 11.1768(19) A, c ¼ 23.057(4) A, a ¼ b ¼ g ¼ 908, V ¼ 4009.7(11) A , Z ¼ 8,
3
21
˚
Dc ¼ 1.260 Mg/m , l(MoKa) ¼ 0.71070 A, m ¼ 0.084 mm
,
F(000) ¼ 1632.
3
hole: 0.503 and 20.213 e A
.168 , u , 27.488, R ¼ 0.0840, wR ¼ 0.1611. S ¼ 1.258, Largest diff. Peak and
2
3
.
˚

100
X. Wang et al.
Figure 1. Crystal structure of 3o.
using an Inova-400 spectrometer. Elemental analyses were carried out using
Carlo Erba 1110 analyzer. X-ray diffraction was measured on a Siemens P4
diffractometer.
General Procedure
A suspension of a mixture of substituted salicylaldehydes 1 (2 mmol), substi-
tuted 1,3-hexanedione 2 (4 mmol) and TEBA (0.1 g) was stirred in water
(10 mL) at 908C for 3–5 h. The crystalline power formed was collected by
filtration, washed with water, and recrystallized from 95% EtOH to give
pure1-oxo-1,2,3,4,9,10- hexahydroxanthene derivatives 3.
2
1
3
a: m.p. 244–2468C. IR (KBr, n, cm ): 3115, 2950, 2890, 1652, 1648,
572, 1551, 1485, 1444, 1369, 1289, 1228, 1187, 1051, 991, 974, 905, 840; H
1
1
NMR (CDCl , d, ppm): 1.81 ꢀ 2.76 (m, 12H, 6CH ), 4.64 (s, 1H, CH),
3
2
7
Anal. calcd for C H O : C 73.53, H 5.85; found C 73.45, H 5.73.
.00 ꢀ 7.03 (3, 3H, ArH), 7.13 ꢀ 7.18 (m, 1H, ArH), 10.81 (b, 1H, OH).
1
9 18 4
2
1
3
b: m.p. 218–2198C. IR (KBr, n, cm ): 3109, 2949, 2884, 1676, 1644,
598, 1481, 1378, 1211, 1219, 1189, 1071, 984, 810, 764; H NMR (CDCl , d,
3
1
1
ppm): 1.82 ꢀ 2.78 (m, 12H, 6CH ), 4.57 (s, 1H, CH), 6.90(d, J ¼ 8.4 Hz, 1H,
2
0
ArH), 7.12 (d, J ¼ 2.4 Hz, 1H, ArH), 7.55 (dd, J ¼ 8.4 Hz, J ¼ 2.4 Hz, 1H,
ArH), 10.74 (b, 1H, OH). Anal. calcd for C H ClO : C 66.19, H 4.97;
4
1
9
17
found C 65.97, H 5.08.
c: m.p. 218–2198C. IR (KBr, n, cm ): 3108, 2945, 2883, 1680, 1644,
2
1
3
598, 1480, 1378, 1270, 1219, 1188, 1147, 1070, 984, 906, 810, 763; H NMR
1
1
(
CDCl , d, ppm): 1.93 ꢀ 2.78 (m, 12H, 6CH ), 4.58 (s, 1H, CH),
3
2

Synthesis of 1-Oxo-hexahydroxanthene Derivatives
101
6
.90(d, J ¼ 8.4 Hz, 1H, ArH), 7.12 (d, J ¼ 2.4 Hz, 1H, ArH), 7.25
0
(dd, J ¼ 8.4 Hz, J ¼ 2.4 Hz, 1H, ArH), 10.72 (b, 1H, OH). Anal. calcd for
C H BrO : C 58.63, H 4.40; found C 58.40, H 4.52.
1
9
17
4
2
1
3
655, 1618, 1570, 1514, 1475, 1426, 1363, 1328, 1250, 1205, 1168, 1040,
d: m.p. 218–2198C. IR (KBr, n, cm ): 3234, 3025, 2976, 2888, 1724,
1
9
6
1
1
58, 827, 811, 740, 686; H NMR (CDCl , d, ppm): 1.90 ꢀ 2.79 (m, 12H,
3
CH ), 4.84 (s, 1H, CH), 7.01(d, J ¼ 8.8 Hz, 1H, ArH), 7.73 (d, J ¼ 2.8 Hz,
2
0
H, ArH), 7.99 (dd, J ¼ 8.8 Hz, J ¼ 2.8 Hz, 1H, ArH), 9.92 (b, 1H, OH).
Anal. calcd for C H NO : C 64.22, H 4.82, N 3.94; found C 64.13, H
1
9
17
6
4
.96, N 3.88.
e: m.p. 218–2198C. IR (KBr, n, cm ): 3140, 2940, 2867, 1718, 1655,
2
1
3
620, 1579, 1454, 1375, 1303, 1229, 1193, 1040, 993, 917, 852, 768; H NMR
1
1
(
CDCl , d, ppm): 1.91 ꢀ 2.78 (m, 12H, 6CH ), 4.51 (s, 1H, CH),
3
2
7
OH). Anal. calcd for C H Cl O : C 60.17, H 4.25; found C 60.01, H 4.30.
.10(d, J ¼ 2.4 Hz, 1H, ArH), 7.37 (d, J ¼ 2.4 Hz, 1H, ArH), 9.25 (b, 1H,
19 16 2 4
2
1
3
614, 1561, 1444, 1395, 1375, 1238, 1169, 1126, 1030, 933, 903, 876, 846,
f: m.p. 218–2198C. IR (KBr, n, cm ): 3124, 2955, 2866, 1712, 1648,
1
7
1
98; H NMR (CDCl , d, ppm): 1.92 ꢀ 2.77 (m, 12H, 6CH ), 4.50 (s, 1H,
3
2
CH), 7.40(d, J ¼ 2.4 Hz, 1H, ArH), 7.51 (d, J ¼ 2.4 Hz, 1H, ArH), 9.40
(
H 3.50.
b, 1H, OH). Anal. calcd for C H Br O : C 48.75, H 3.44; found C 48.66,
1
9
16
2
4
21
3
598, 1557, 1425, 1390, 1280, 1229, 1188, 1130, 1068, 998, 910, 806, 725; H
g: m.p. 218–2198C. IR (KBr, n, cm ): 3187, 3062, 2939, 2868, 1644,
1
1
NMR (CDCl , d, ppm): 1.73 ꢀ 2.87 (m, 12H, 6CH ), 5.22 (s, 1H, CH),
3
2
7
.25 ꢀ 7.78 (m, 5H, ArH), 11.00 (b, 1H, OH). Anal. calcd for C H O : C
2
3 20 4
7
6.65, H 5.59; found C 76.50, H 5.72.
1
4
3
3
h: m.p. 206–2088C, (Lit. m.p. 203–2058C)
21
i: m.p. 218–2198C. IR (KBr, n, cm ): 3178, 2951, 2869, 1641, 1590,
1
1
481, 1460, 1371, 1313, 1247, 1188, 1145, 1013, 985, 810, 755; H NMR
(
CDCl , d, ppm): 0.99 (s, 3H, CH ), 1.02 (s, 6H, 2CH ), 1.13 (s, 3H, CH ),
3 3 3 3
1
.98 ꢀ 2.60 (m, 8H, 4CH ), 4.61 (s, 1H, CH), 6.95(d, J ¼ 8.8 Hz, 1H,
2
0
ArH), 6.98 (d, J ¼ 2.4 Hz, 1H, ArH), 7.10 (dd, J ¼ 8.8 Hz, J ¼ 2.4 Hz, 1H,
ArH), 10.40 (b, 1H, OH). Anal. calcd for C H ClO : C 68.91, H 6.29;
2
3
25
4
found C 68.77, H 6.50.
j: m.p. 218–2198C. IR (KBr, n, cm ): 3114, 2965, 2873, 1619, 1562,
2
1
3
475, 1372, 1296, 1229, 1178, 1152, 1070, 1034, 1014, 886, 819; H NMR
1
1
(
CDCl , d, ppm): 0.99 (s, 3H, CH ), 1.02 (s, 6H, CH ), 1.12 (s, 3H, CH ),
3
3
3
3
1
.98 ꢀ 2.60 (m, 8H, 4CH ), 4.60 (s, 1H, CH), 6.91(d, J ¼ 8.4 Hz, 1H,
2
0
ArH), 7.13 (d, J ¼ 2.4 Hz, 1H, ArH), 7.25 (dd, J ¼ 8.4 Hz, J ¼ 2.4 Hz, 1H,
ArH), 10.38 (b, 1H, OH) Anal. calcd for C H BrO : C 62.03, H 5.66;
2
3
25
4
found C 61.95, H 5.78.
3
2
1
k: m.p. 218–2198C. IR (KBr, n, cm ): 3196, 2955, 2868, 1649, 1598,
1
1526, 1475, 1362, 1332, 1229, 1193, 1147, 1091, 825, 732 H NMR (CDCl ,
3
d, ppm): 0.99 (s, 3H, CH ), 1.00 (s, 3H, CH ), 1.04 (s, 3H, CH ), 1.15 (s, 3H,
3
3
3

102
X. Wang et al.
CH ), 1.96 ꢀ 2.64 (m, 8H, 4CH ), 4.68 (s, 1H, CH), 7.13 (d, J ¼ 8.8 Hz, 1H,
3
2
0
ArH), 7.94 (d, J ¼ 2.8 Hz, 1H, ArH), 8.06 (dd, J ¼ 8.8 Hz, J ¼ 2.8 Hz, 1H,
ArH), 10.32 (b, 1H, OH) Anal. calcd for C H NO : C 67.14, H 6.12, N
6
23
25
3
.40; found C 67.06, H 6.17, N 3.52.
l: m.p. 218–2198C. IR (KBr, n, cm ): 3155, 2955, 2868, 1669, 1629,
603, 1464, 1419, 1363, 1301, 1188, 1163, 1132, 994, 906, 855, 804, 732,
2
1
3
1
6
1
91; H NMR (CDCl , d, ppm): 1.00 (s, 3H, CH ), 1.01 (s, 3H, CH ), 1.03
3
3
3
(
s, 3H, CH ), 1.14 (s, 3H, CH ), 2.00 ꢀ 2.68 (m, 8H, 4CH ), 4.60 (s, 1H,
3
3
2
CH), 6.89(d, J ¼ 2.0 Hz, 1H, ArH), 7.21 (d, J ¼ 2.0 Hz, 1H, ArH), 8.96
(b, 1H, OH). Anal. calcd for C H Cl O : C 63.46, H 5.56; found C 63.25,
H 5.70.
23 24 2 4
2
1
3
610, 1571, 1461, 1379, 1316, 1260, 1209, 1144, 1087, 1017, 903, 868, 815,
m: m.p. 218–2198C. IR (KBr, n, cm ): 3205, 2975, 2873, 1677, 1659,
1
7
1
88, 692; H NMR (CDCl , d, ppm): 1.00 (s, 3H, CH ), 1.01 (s, 3H, CH ), 1.04
3
3
3
(
s, 3H, CH ), 1.14 (s, 3H, CH ), 2.00 ꢀ 2.57 (m, 8H, 4CH ), 4.60 (s, 1H, CH),
3
3
2
7
OH). Anal. calcd for C H Br O : C 52.69, H 4.61; found C 52.75, H 4.60.
.06(d, J ¼ 2.0 Hz, 1H, ArH), 7.51 (d, J ¼ 2.0 Hz, 1H, ArH), 10.30 (b, 1H,
23 24 2 4
1
4
3
n: m.p. 2245–2488C, (Lit. m.p. 241–2438C).
21
3o: m.p. 218–2198C. IR (KBr, n, cm ): 3142, 3011, 2955, 2873, 1681,
618, 1582, 1490, 1367, 1311, 1250, 1224, 1152, 1075, 1034, 886, 809; H
1
1
NMR (CDCl , d, ppm): 0.99 (s, 3H, CH ), 1.00 (s, 3H, CH ), 1.02 (s, 3H,
3
3
3
CH ), 1.12 (s, 3H, CH ), 1.96 ꢀ 2.61 (m, 11H, 4CH þ CH ), 4.62 (s, 1H,
3
3
2
3
CH), 6.80(d, J ¼ 1.6 Hz, 1H, ArH), 6.90 (d, J ¼ 8.0 Hz, 1H, ArH), 6.94 (dd,
0
J ¼ 8.0 Hz, J ¼ 1.6 Hz, 1H, ArH), 10.50 (b, 1H, OH). Anal. calcd for
C H O : C 75.76, H 7.42; found C 75.66, H 7.60.
4 28 4
2
ACKNOWLEDGMENT
We are grateful to the Foundation of the “Surpassing Project” of Jiangsu
Province and Natural Science Foundation of the Education Committee of
Jiangsu Province (04KJB150139) for financial support.
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