An efficient synthesis of 14-Aryl or Alkyl-14H-dibenzo[a. j]xanthenes using reusable HBF4-SiO2 catalyst under thermal and solvent-free conditions

Article abstract of DOI:10.1002/jccs.200900055

A simple and convenient procedure for the synthesis of 14-aryl or alkyl-14H-dibenzo[a.j]xanthene derivatives is described through a one-pot condensation of β-naphthol with various aryl or alkyl aldehydes in the presence of HBF₄-SiO₂

Full text of DOI:10.1002/jccs.200900055

Journal of the Chinese Chemical Society, 2009, 56, 381-385
381
An Efficient Synthesis of 14-Aryl or Alkyl-14H-dibenzo[a. j]xanthenes
Using Reusable HBF4-SiO2 Catalyst Under Thermal and Solvent-Free
Conditions
Gui-Yun Fu* (
Xiao-Gang Chen (
), Yi-Xiang Huang (
) and Xiao-Ling Liu (
College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022, P. R. China
),
)
A simple and convenient procedure for the synthesis of 14-aryl or alkyl-14H-dibenzo[a.j]xanthene
derivatives is described through a one-pot condensation of b-naphthol with various aryl or alkyl alde-
hydes in the presence of HBF4-SiO2 as the catalyst under thermal and solvent-free conditions.
Keywords: Xanthene; HBF4-SiO2; Aldehyde; b-Naphthol; Solvent-free; One-pot condensation.
The synthesis of xanthenes, especially enzoxanthenes,
has emerged as a powerful tool in organic synthesis due to
their wide range of biological and therapeutic properties
such as antibacterial,1 antiviral2 and antiinflammatory ac-
tivities,3 as well as in photodynamic therapy4 and for antag-
onism of the paralyzing action of zoxazolamine.5,6 Further-
more, due to their useful spectroscopic properties, they are
used as dyes,7,8 in laser technologies,9 and in fluorescent
materials for visualization of biomolecules.10 Thus, the
synthesis of benzoxanthene derivatives currently is of great
interest. Various methods have been reported for the syn-
thesis of benzoxanthenes, including (a) dehydration of bis-
(2-hydroxy-1-naphthyl)methane using POCl3 11 or by boil-
ing acetic acid diester of bis(2-hydroxy-1-naphthyl)meth-
ane,12 (b) condensation of b-naphthol with aliphatic and ar-
omatic aldehydes in the presence of hydrochloric acid or
phosphoric acid13 and also sulfuric acid14 in acetic acid as
solvent. However, all these methods have many disadvan-
tages such as low yields, the need for a prolonged reaction
time, the use of toxic organic solvents, excess reagents, and
harsh reaction conditions. Because of these drawbacks, the
reaction has been improved by mixing b-naphthol with al-
dehydes in the presence of a catalyst, such as p-toluene-
sulfonic acid,15,16 sulfamic acid,17 I2,18 Amberlyst-15,19 sil-
ica sulfuric acid,20 Al(HSO4)3,21 NaHSO4,22 Selectflu-
orÔ,23 K5CoW12O40·3H2O24 and hetero polyacid.25 Al-
though some of these methods have convenient protocols
with good to high yields, the majority of these methods suf-
fer at least from one of the following disadvantages: harsh
reaction conditions, long reaction time, tedious experimen-
tal procedures, the use of toxic solvents and catalysts.
Hence, a practical and more efficient method for the syn-
thesis of dibenzoxanthene derivatives would still be of in-
terest. Over the last few years, there has been a consider-
able growth in interest in the use of solid-phase reagents in
organic synthesis because of their ease of handing, en-
hanced reaction rates, greater selectivity, simple workup
and recoverablity of catalysts.26 Among the various hetero-
geneous catalysts, particularly, silica-supported reagents
have advantages of low cost, ease of preparation, and cata-
lyst recycling.27 Herein we demonstrate tetrafluorooric
acid adsorbed on silica gel (HBF4-SiO2)28 as an inexpen-
sive, highly efficient, heterogeneous, and reusable catalyst
for the preparation of 14-aryl or alkyl-14H-dibenzo[a.j]-
xanthene derivatives by the condensation reaction of vari-
ous aryl or alkyl aldehydes with b-naphthol under thermal
and solvent-free conditions (Scheme I). The present method
not only affords the products in excellent yields but also
avoids the problems associated with catalyst cost, handing,
safety and pollution.
Scheme I
* Corresponding author. E-mail: fuguiyunjxsd@163.com

382 J. Chin. Chem. Soc., Vol. 56, No. 2, 2009
Fu et al.
In the first instance, the catalytic effect of HBF4-SiO2
on the condensation reaction of benzaldehyde 1a (1.0
mmol) and b-naphthol 2 (2.0 mmol) under solvent-free
conditions was investigated. After many studies on the
above condensation, we found that when less than 3 mol %
of HBF4-SiO2 was applied, lower yields of the correspond-
ing product (Table 1, entries 2-7) resulted, whereas use of
more than 3 mol % did not improve the yield (Table 1, en-
tries 10 and 11). When attempts were made to carry out this
reaction for 3 h in the absence of HBF4-SiO2, the substrate
was recovered almost quantitatively (Table 1, entry 1).
Next, for optimization of temperature, the reaction
was performed using benzaldehyde 1a (1.0 mmol) and
b-naphthol 2 (2.0 mmol) in the presence of HBF4-SiO2 (3
mol %) under thermal solvent-free conditions. As can be
seen from Table 1 (entry 8), the shorter time and excellent
yield (94%) for 14H-phenyldibenzo[a. j]xanthene (3a)
were achieved at 125 °C.
Table 1. Preparation of 14H-phenyldibenzo[a. j]xanthene (3a)
under solvent-free conditions
Entry HBF4-SiO2 Temperature (°C) Time (min) Yielda (%)
1
None
125 °C
050 °C
080 °C
100 °C
125 °C
125 °C
125 °C
125 °C
125 °C
125 °C
125 °C
1800
30
30
30
30
40
30
30
40
40
40
–
2
0.01 mmol
0.01 mmol
0.01 mmol
0.01 mmol
0.01 mmol
0.02 mmol
0.03 mmol
0.03 mmol
0.04 mmol
0.05 mmol
45
70
77
80
80
85
94
94
94
94
3
4
5
6
7
8
9
10
11
a Yield refers to the pure isolated product.
Table 2. Synthesis of 14-aryl or alkyl-14H-dibenzo[a. j]xan-
thenesa
Entry
R (aldehyde)
C6H5 (1a)
Time (min) Product Yieldb (%)
Based on the above results, we also conducted the
same reactions using aldehydes 1b-1l and 2 in the presence
of HBF4-SiO2 under similar conditions. As expected, both
aromatic aldehydes containing electron-donating as well as
electron-withdrawing groups, and aliphatic aldehyde were
utilized in the present case to form the corresponding ben-
zoxanthenes 3 in high yields (Table 2). In addition, as seen
from Table 2, the aromatic aldehydes with electron donat-
ing groups are generally more reactive than their corre-
sponding benzaldehydes with electron withdrawing groups
and give the desired product in a short reaction time; how-
ever, the substituent character seemed to result in no obvious
effect on the reaction yields.
1
30
25
22
20
18
40
37
28
31
34
30
32
3a
3b
3c
3d
3e
3f
94
92
92
91
88
94
95
93
94
88
90
89
2
4-CH3C6H4 (1b)
4-CH3OC6H4 (1c)
2,5-(CH3O)2C6H3 (1d)
4-HOC6H4 (1e)
4-NO2C6H4 (1f)
2-NO2C6H4 (1g)
4-ClC6H4 (1h)
3
4
5
6
7
3g
3h
3i
8
9
3-ClC6H4 (1i)
10
11
12
2,4-Cl2C6H3 (1j)
3-FC6H4 (1k)
3j
3k
3l
CH3CH2 (1l)
a Aldehyde (1.0 mmol), b-napthol (2.0 mmol); HBF4-SiO2 (0.03
mmol).
b Yield refers to the pure isolated products.
In view of a greener chemistry, efficient recovery and
reuse of the catalyst is highly desirable. Thus the recovery
and reusability of HBF4-SiO2 was investigated. After the
reaction was completed, ethyl acetate was added until the
solid crude product was dissolved. Then, HBF4-SiO2 as the
catalyst was isolated from the mixture of the reaction by
simple filtration and reused again after washing with ethyl
acetate. The reusability of HBF4-SiO2 was examined effi-
ciently without any activation by using benzaldehyde (1a)
as a model substrate in the above experimental procedure.
The recovered HBF4-SiO2 was reused directly for three
consecutive condensation reactions of benzaldehyde (1a)
with b-naphthol (2) affording 92%, 90%, 88% yields in 32
min, 35 min, 38 min, respectively.
14-aryl or alkyl-14H-dibenzo[a. j]xanthene derivatives by
the condensation of various aldehydes with b-naphthol us-
ing silica-supported fluoroboric acid as a heterogeneous
catalyst under thermal and solvent-free conditions. This
methodology offers very attractive features such as re-
duced reaction times, higher yields, economic viability of
catalyst, and mild nature of silica-supported fluoroboric
acid. This simple procedure combined with ease of recov-
ery and reuse of catalyst make this method economic, be-
nign and a waste-free chemical process for the synthesis of
14-aryl or alkyl-14H-dibenzo[a. j]xanthenes.
EXPERIMENTAL SECTION
In conclusion, we have developed a simple, conve-
nient and effective method for easy one-pot synthesis of
Melting points were determined on an X4 melting

Synthesis of 14H-Dibenzo[a. j]xanthenes
J. Chin. Chem. Soc., Vol. 56, No. 2, 2009 383
point apparatus and are uncorrected. 1H NMR (400 MHz)
and 13C NMR (100 MHz) spectra were recorded on a Bruker
Avance (400 MHz) spectrometer using CDCl3 as the sol-
vent and TMS as an internal standard. FT-IR spectra were
taken on a Perkin-Elmer SP One FT-IR spectrophotometer.
Microanalyses were performed with a PE 2400 elemental
analyzer. Mass spectra (EI, 70 eV) were recorded on an
HP5989B mass spectrometer. All reagents were purchased
from commercial sources and were used without further
purification.
6.45 (s, 1H), 2.12 (s, 3H); 13C NMR: d = 147.9, 147.7,
142.6, 135.8, 130.7, 128.8, 128.5, 127.6, 126.7, 124.4,
123.3, 117.5, 117.3, 117.1, 37.2, 20.3; IR (KBr): n = 3070,
2915, 1624, 1598, 1515, 1465, 1436, 1404, 1260, 1125,
1088, 968, 840, 815, 786, 745 cm-1; EI-MS: m/z (%) = 372
(M+); Anal. Calcd for C28H20O: C, 90.29; H, 5.41. Found:
C, 90.37; H, 5.48.
14-(4-Methoxyphenyl)-14H-dibenzo[a. j]xanthene (3c)
Yellow solid, mp 204-206 °C (lit.16 mp 205 °C); 1H
NMR: d = 8.42 (d, J = 8.9 Hz, 2H), 7.83 (d, J = 8.8 Hz, 2H),
7.76 (d, J = 8.8 Hz, 2H), 7.58 (t, J = 8.5 Hz, 2H), 7.50 (d, J =
8.8 Hz, 2H), 7.44-7.36 (m, 4H), 6.71 (d, J = 8.9 Hz, 2H),
6.51 (s, 1H), 3.70 (s, 3H); 13C NMR: d = 158.4, 149.0,
137.8, 134.2, 131.4, 130.8, 129.2, 129.1, 127.1, 124.5,
123.2, 118.4, 117.8, 114.5, 54.1, 37.4; IR (KBr): n = 3040,
2915, 1617, 1580, 1515, 1465, 1436, 1404, 1250, 1125,
1088, 968, 825, 805, 745 cm-1; EI-MS: m/z (%) = 388 (M+);
Anal. Calcd for C28H20O2: C, 86.57; H, 5.19. Found: C,
86.45; H, 5.27.
Preparation of HBF4-SiO2
HBF4 (1.65 g, as a 40% aq solution) was added to the
suspension of silica gel (13.35 g, 230-400 mesh) in Et2O
(40 mL). The mixture was concentrated and the residue
was dried under vacuum at 100 °C for 72 h to afford HBF4-
SiO2 (0.5 mmol/g) as a free-flowing powder.
General Procedure for the Synthesis of 14-Aryl or
Alkyl-14H-dibenzo[a.j]xanthenes
To a mixture of aldehyde (1.0 mmol) and b-naphthol
(2.0 mmol), HBF4-SiO2 (60 mg, 0.03 mmol) was added and
the mixture was heated in an oil bath at 125 °C for the ap-
propriate time (Table 2). After completion of the reaction,
as monitored by TLC, the reaction mixture was cooled to
25 °C, and ethyl acetate (30 mL) was added until the solid
crude product was dissolved. Then, the heterogeneous cat-
alyst was isolated from the mixture of the reaction by sim-
ple filtration and washing with ethyl acetate (2 ´ 5 mL).
The filtrated organic solution was concentrated to afford
crude product, which was recrystallized from ethyl alcohol
to give pure product.
14-(2,5-Dimethoxyphenyl)-14H-dibenzo[a. j]xanthene
(3d)
Yellow solid, mp 169-171 °C (lit.21 mp 169 °C); 1H
NMR: d = 8.60 (d, J = 8.5 Hz, 2H), 7.82 (d, J = 8.0 Hz, 2H),
7.77 (d, J = 8.8 Hz, 2H), 7.57 (t, J = 7.5 Hz, 2H), 7.49 (d, J =
8.8 Hz, 2H), 7.46 (t, J = 7.4 Hz, 2H), 6.89 (s, 1H), 6.85 (s,
1H), 6.77 (d, J = 9.0 Hz, 1H), 6.47 (d, J = 6.0 Hz, 1H), 4.25
(s, 3H), 3.46 (s, 3H); 13C NMR: d = 154.0, 148.7, 148.2,
135.5, 132.0, 129.8, 129.7, 128.7, 128.4, 126.7, 124.3,
123.5, 118.2, 117.0, 111.8, 111.4, 56.0, 55.1, 30.6; IR
(KBr): n = 2926, 2832, 1620, 1595, 1460, 1432, 1405,
1255, 1208, 1175, 1044, 966, 850, 815, 800, 745, 701 cm-1;
EI-MS: m/z (%) = 418 (M+); Anal. Calcd for C29H22O3: C,
83.23; H, 5.30. Found: C, 83.31; H, 5.36.
14-Phenyl-14H-dibenzo[a. j]xanthene (3a)
Pale yellow solid, mp 182-183 °C (lit.14 mp 183 °C);
1H NMR: d = 8.40 (d, J = 8.4 Hz, 2H), 7.82 (d, J = 7.9 Hz,
2H), 7.79 (d, J = 8.8 Hz, 2H), 7.58 (t, J = 7.7 Hz, 2H), 7.53
(d, J = 7.5 Hz, 2H), 7.49 (d, J = 8.8 Hz, 2H), 7.41 (t, J = 7.5
Hz, 2H), 7.15 (t, J = 7.5 Hz, 2H), 7.00 (t, J = 7.5 Hz, 1H),
6.49 (s, 1H); 13C NMR: d = 148.7, 145.0, 131.3, 131.0,
128.8, 128.5, 128.1, 126.8, 126.5, 126.3, 124.2, 122.6,
117.9, 117.4, 38.2; IR (KBr): n = 3068, 3020, 2885, 1620,
1590, 1512, 1488, 1457, 1402, 1252, 1080, 1025, 965, 825,
745, 700 cm-1; EI-MS: m/z (%) = 358 (M+); Anal. Calcd for
C27H18O: C, 90.47; H, 5.06. Found: C, 90.41; H, 5.14.
14-(4-Methylphenyl)-14H-dibenzo[a. j]xanthene (3b)
Yellow solid, Mp 227-228 °C (lit.14 mp 228 °C); 1H
NMR: d = 8.38 (d, J = 8.5 Hz, 2H), 7.82 (d, J = 8.8 Hz, 2H),
7.78 (d, J = 8.8 Hz, 2H), 7.57 (t, J = 8.5 Hz, 2H), 7.49 (d, J =
8.8 Hz, 2H), 7.45-7.37 (m, 4H), 6.94 (d, J = 7.8 Hz, 2H),
14-(4-Hydroxyphenyl)-14H-dibenzo[a, j]xanthene (3e)
1
Pink solid, mp 140-141 °C (lit.23 mp 140 °C); H
NMR: d = 8.35-6.55 (m, 16H), 6.45 (s, 1H), 4.98 (br s, 1H);
13C NMR: d = 154.1, 149.0, 137.7, 131.7, 131.5, 129.7,
129.2, 129.0, 127.3, 124.7, 123.2, 118.5, 117.8, 115.8,
37.6; IR (KBr): n = 3405, 1595, 1512, 1400, 1250, 1244,
816, 750, 695 cm-1; EI-MS: m/z (%) = 374 (M+); Anal.
Calcd for C27H18O2: C, 86.61; H, 4.85. Found: C, 86.55; H,
4.80.
14-(4-Nitrophenyl)-14H-dibenzo[a. j]xanthene (3f)
Yellow solid, mp 311-313 °C (lit.16 mp 312 °C); 1H
NMR: d = 8.30 (d, J = 8.5 Hz, 2H), 7.98 (d, J = 8.7 Hz, 2H),
7.85 (d, J = 4.0 Hz, 2H), 7.82 (d, J = 5.5 Hz, 2H), 7.66 (d, J
= 8.7 Hz, 2H), 7.61 (t, J = 5.5 Hz, 2H), 7.50 (d, J = 8.8 Hz,

384 J. Chin. Chem. Soc., Vol. 56, No. 2, 2009
Fu et al.
2H), 7.45 (t, J = 7.9 Hz, 2H), 6.60 (s, 1H); 13C NMR: d =
152.5, 148.0, 145.8, 135.1, 130.9, 130.7, 129.7, 128.6,
127.3, 124.7, 123.5, 123.0, 117.8, 116.2, 36.5; IR (KBr): n
= 3065, 2930, 1622, 1590, 1520, 1458, 1401, 1342, 1200,
1141, 1108, 1015, 965, 850, 828, 810, 743 cm-1; EI-MS:
m/z (%) = 403 (M+); Anal. Calcd for C27H17NO3: C, 80.38;
H, 4.25; N, 3.47. Found: C, 80.30; H, 4.35; N, 3.55.
14-(2-Nitrophenyl)-14H-dibenzo[a. j]xanthene (3g)
Yellow solid, mp 292-293 °C (lit.17 mp 293 °C); 1H
NMR: d = 8.59-7.15 (m, 16H), 7.54 (s, 1H); 13C NMR: d =
150.1, 147.8, 141.3, 134.5, 132.7, 132.0, 130.5, 129.8,
129.6, 129.2, 128.1, 127.6, 125.5, 125.1, 124.5, 122.9,
118.5, 118.1, 33.1; IR (KBr): n = 3402, 3056, 2928, 1615,
1594, 1524, 1352, 1243, 1140, 815, 750 cm-1; EI-MS: m/z
(%) = 403 (M+); Anal. Calcd for C27H17NO3: C, 80.38; H,
4.25; N, 3.47. Found: C, 80.26; H, 4.32; N, 3.57.
NMR: d = 148.8, 142.2, 132.9, 132.5, 131.6, 130.8, 130.5,
129.4, 129.1, 128.8, 128.5, 127.1, 124.4, 123.2, 117.9,
117.5, 34.2; IR (KBr): n = 3055, 2922, 1620, 1590, 1560,
1515, 1458, 1406, 1242, 1210, 1140, 1101, 1042, 962, 865,
838, 810, 742, 700 cm-1; EI-MS: m/z (%) = 427 (M+); Anal.
Calcd for C27H16Cl2O: C, 75.89; H, 3.77. Found: C, 75.96;
H, 3.84.
14-(3-Fluorophenyl)-14H-dibenzo[a. j]xanthene (3k)
Brown solid, mp 258-260 °C (lit.23 mp 259 °C); 1H
NMR: d = 8.38 (d, J = 8.6 Hz, 2H), 7.89 (d, J = 8.6 Hz, 2H),
7.78 (d, J = 8.9 Hz, 2H), 7.63 (t, J = 7.0 Hz, 2H), 7.53 (d, J =
8.9 Hz, 2H), 7.50-7.45 (m, 4H), 7.13 (t, J = 8.0 Hz, 1H),
6.73 (d, J = 8.7 Hz, 1H), 6.50 (1H, s); 13C NMR: d = 165.0,
161.5, 149.3, 148.0 (JC-F = 6.3 Hz), 147.9, 131.7 (JC-F
=
19.4 Hz), 131.5, 130.2 and 130.1 (JC-F = 8.2 Hz), 129.4,
129.3, 127.5, 124.8, 124.4 and 124.1 (JC-F = 2.8 Hz), 122.8,
118.2, 117.1, 115.8 and 115.6 (JC-F = 21.5 Hz), 114.0 and
113.7 (JC-F = 21.5 Hz), 38.2; IR (KBr): n = 3155, 2925,
1621, 1594, 1550, 1456, 1404, 1241, 1208, 1104, 1068,
967, 818, 749, 698 cm-1. EI-MS: m/z (%) = 376 (M+); Anal.
Calcd for C27H17FO3: C, 86.15; H, 4.55. Found: C, 86.06;
H, 4.46.
14-(4-Chlorophenyl)-14H-dibenzo[a. j]xanthene (3h)
Brown solid, mp 287-288 °C (lit.16 mp 289 °C); 1H
NMR: d = 8.45 (d, J = 8.5 Hz, 2H), 8.01 (d, J = 8.7 Hz, 2H),
7.88 (d, J = 4.0 Hz, 2H), 7.84 (d, J = 5.5 Hz, 2H), 7.69 (d, J
= 8.7 Hz, 2H), 7.64 (t, J = 5.5 Hz, 2H), 7.55 (d, J = 8.8 Hz,
2H), 7.50 (t, J = 7.9 Hz, 2H), 7.46 (s, 1H); 13C NMR: d =
156.0, 147.8, 132.8, 131.2, 129.3, 128.8, 128.3, 127.0,
126.8, 126.5, 124.7, 119.3, 118.2, 117.8, 33.5; IR (KBr): n
= 3050, 2925, 1620, 1595, 1456, 1431, 1396, 1242, 1060,
960, 824, 778, 695 cm-1; EI-MS: m/z (%) = 392 (M+); Anal.
Calcd for C27H17ClO: C, 82.54; H, 4.36. Found: C, 82.46;
H, 4.44.
14-Ethyl-14H-dibenzo[a. j]xanthene (3l)
Pale yellow solid, mp 151-152 °C (lit.14 mp 152 °C);
1H NMR: d = 8.25 (d, J = 8.0 Hz, 2H), 7.89-7.71 (m, 4H),
7.60-7.50 (m, 2H), 7.43-7.33 (m, 4H), 5.41 (t, J = 7.2 Hz,
1H), 2.26 (m, 2H), 0.87 (t, J = 7.5 Hz, 3H); 13C NMR: d =
142.4, 137.1, 131.8, 130.2, 128.5, 128.1, 126.5, 126.3,
124.4, 117.2, 37.8, 23.5, 14.3; IR (KBr): n = 3050, 2923,
1622, 1591, 1560, 1516, 1457, 1386, 1240, 1210, 1140,
1100, 1045, 965, 828, 810, 745, 696 cm-1; EI-MS: m/z (%)
= 310 (M+); Anal. Calcd for C23H18O: C, 89.00; H, 5.85.
Found: C, 89.12; H, 5.93.
14-(3-Chlorophenyl)-14H-dibenzo[a. j]xanthene (3i)
Brown solid, mp 172-173 °C (lit.21 mp 173 °C); 1H
NMR: d = 8.30 (d, J = 8.4 Hz, 2H), 7.86 (d, J = 8.6 Hz, 2H),
7.76 (d, J = 9.0 Hz, 2H), 7.60 (t, J = 7.0 Hz, 2H), 7.50 (d, J =
8.9 Hz, 2H), 7.48-7.43 (m, 4H), 7.10 (t, J = 8.0 Hz, 1H),
6.96 (d, J = 8.7 Hz, 1H), 6.45 (1H, s); 13C NMR: d = 148.5,
146.8, 134.5, 131.2, 131.0, 129.7, 129.1, 128.8, 128.2,
127.1, 126.8, 126.4, 124.5, 122.4, 118.1, 116.4, 37.8; IR
(KBr): n = 3053, 2926, 1622, 1590, 1508, 1455, 1430,
1398, 1245, 1064, 959, 815, 775, 745, 690 cm-1; EI-MS:
m/z (%) = 392 (M+); Anal. Calcd for C27H17ClO: C, 82.54;
H, 4.36. Found: C, 82.48; H, 4.42.
ACKNOWLEDGEMENTS
We gratefully acknowledge financial support from
the Natural Science Foundation of Jiangxi Province (No.
2007GZW0185) and the Research Program of Jiangxi
Province Department of Education (No. GJJ08165).
14-(2,4-Dichlorophenyl)-14H-dibenzo[a. j]xanthene
Received August 29, 2008.
(3j)
Brown solid, mp 227-228 °C (lit.22 mp 228 °C); 1H
NMR: d = 8.65 (d, J = 8.5 Hz, 2H), 7.82 (d, J = 7.9 Hz, 2H),
7.80 (d, J = 8.7 Hz, 2H), 7.63 (t, J = 7.5 Hz, 2H), 7.48 (d, J =
8.7 Hz, 2H), 7.45 (t, J = 7.5 Hz, 2H), 7.31 (d, J = 8.6 Hz,
REFERENCES
1. Hideo, T. Jpn. Tokkyo Koho JP 56005480, 1981; Chem.
Abstr. 1981, 95, 80922b.
2. Lambert, R. W.; Martin, J. A.; Merrett, J. H.; Parkes, K. E.
B.; Thomas, G. J. PCT Int. Appl. WO 9706178, 1997; Chem.
1H), 7.27 (s, 1H), 6.88 (d, J = 6.8 Hz, 1H), 6.75 (s, 1H); 13
C

Synthesis of 14H-Dibenzo[a. j]xanthenes
J. Chin. Chem. Soc., Vol. 56, No. 2, 2009 385
Abstr. 1997, 126, 212377y.
2005, 955.
3. Poupelin, J. P.; Saint-Ruf, G.; Foussard-Blanpin, O.;
Narcisse, G.; Uchida-Ernouf, G.; Lacroix, R. Eur. J. Med.
Chem. 1978, 13, 67.
17. Rajitha, B.; Kumar, B. S.; Reddy, Y. T.; Reddy, P. N.;
Sreenivasulu, N. Tetrahedron Lett. 2005, 46, 8691.
18. Das, B.; Ravikanth, B.; Ramu, R.; Laxminarayana, K.; Rao,
B. V. J. Mol. Catal. A: Chem. 2006, 255, 74.
4. Ion, R. M.; Frackowiak, D.; Planner, A.; Wiktorowicz, K.
Acta Biochim. Pol. 1998, 45, 833.
19. Ko, S.; Yao, C. F. Tetrahedron Lett. 2006, 47, 8827.
20. Shaterian, H. R.; Ghashang, M.; Hassankhani, A. Dyes
Pigm. 2008, 76, 564.
5. Saint-Ruf, G.; De, A.; Hieu, H. T. Bull. Chim. Ther. 1972, 7,
83.
6. Saint-Ruf, G.; Hieu, H. T.; Poupelin, J. P. Naturwissen-
schaften 1975, 62, 584.
21. Shaterian, H. R.; Ghashang, M.; Mir, N. Arkivoc 2007, 15, 1.
22. Shaterian, H. R.; Doostmohammadi, R.; Ghashang, M.
Chin. J. Chem. 2008, 26, 338.
7. Menchen, S. M.; Benson, S. C.; Lam, J. Y. L.; Zhen, W.; Sun,
D.; Rosenblum, B. B.; Khan, S. H.; Taing, M. U.S. Patent,
US 6583168, 2003; Chem. Abstr. 2003, 139, 54287f.
8. Banerjee, A.; Mukherjee, A. K. Stain Technol. 1981, 56, 83.
9. Sirkecioglu, O.; Talinli, N.; Akar, A. J. Chem. Res. (S) 1995,
502.
23. Kumara, P. S.; Kumara, B. S.; Rajitha, B.; Reddy, P. N.;
Sreenivasulua, N.; Reddy, Y. T. Arkivoc 2006, 12, 46.
24. Nagarapu, L.; Kantevari, S.; Mahankhali, V. C.; Apuri, S.
Catal. Commun. 2007, 8, 1173.
25. Mohammadpour Amini, M.; Seyyedhamzeh, M.; Bazgir, A.
Appl. Catal. A: Gen. 2007, 323, 242.
10. Knight, C. G.; Stephens, T. Biochem. J. 1989, 258, 683.
11. Wolf, W. Chem. Ber. 1893, 26, 83.
26. Smith, K. Ed. Solid Supports and Catalysts in Organic Syn-
thesis; Prentice Hall: New York, 1992.
12. Rosebush, I. K. Das Leder 1955, 6, 58.
13. Khorramabadi-zad, A.; Kazemi, Z.; Amini Rudbari, H. J.
Korean Chem. Soc. 2002, 46, 541.
27. Shimizu, K.; Hayashi, E.; Hatamachi, T.; Kodama, T.;
Kitayama, Y. Tetrahedron Lett. 2004, 45, 5135.
14. Sarma, R. J.; Baruah, J. B. Dyes Pigm. 2005, 64, 91.
15. Khorramabadi-zad, A.; Akbari, S. A.; Shiri, A.; Veisi, H. J.
Chem. Res. (S) 2005, 277.
28. HBF4-SiO2 is not commercially available and was invented
by Chakraborti and Gulhane (See ref. Chakraborti, A. K.;
Gulhane, R. Tetrahedron Lett. 2003, 44, 3521).
16. Khosropour, A. R.; Khodaei, M. M.; Moghannian, H. Synlett