Synthesis of some new indeno[1′,2′:3,4]fluoreno[1,2-d]oxonine-5,11,16,21-tetraones and oxocyclohex-1-en-1-yl-hydro-1H-xanthen-1-ones

Article abstract of DOI:10.1080/00397911.2019.1683205

The novel oxonine 2, 4 have been synthesized by the reaction of 1,3-indandione with 4-bromo-2-hydroxybenzaldehyde and/or 2-hydroxy-1-naphthaldehyde in the presence of 1,3-diaminopropan-2-ol as green basic catalyst. On the other hand, the reaction of 1,3-c

Full text of DOI:10.1080/00397911.2019.1683205

Synthetic Communications
An International Journal for Rapid Communication of Synthetic Organic
Chemistry
ISSN: 0039-7911 (Print) 1532-2432 (Online) Journal homepage: https://www.tandfonline.com/loi/lsyc20
Synthesis of some new
indeno[1′,2′:3,4]fluoreno[1,2-d]oxonine-5,11,16,21-
tetraones and oxocyclohex-1-en-1-yl-hydro-1H-
xanthen-1-ones
Antar A. Abdelhamid, Shaaban K. Mohamed & Amer A. Amer
To cite this article: Antar A. Abdelhamid, Shaaban K. Mohamed & Amer A. Amer (2019):
Synthesis of some new indeno[1′,2′:3,4]fluoreno[1,2-d]oxonine-5,11,16,21-tetraones
and oxocyclohex-1-en-1-yl-hydro-1H-xanthen-1-ones, Synthetic Communications, DOI:
10.1080/00397911.2019.1683205
To link to this article: https://doi.org/10.1080/00397911.2019.1683205
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SYNTHETIC COMMUNICATIONS
https://doi.org/10.1080/00397911.2019.1683205
0
0
Synthesis of some new indeno[1 ,2 :3,4]fluoreno[1,2-
d]oxonine-5,11,16,21-tetraones and oxocyclohex-1-en-1-yl-
hydro-1H-xanthen-1-ones
a
b,c
a
Antar A. Abdelhamid , Shaaban K. Mohamed , and Amer A. Amer
a
b
Department of Chemistry, Faculty of Science, Sohag University, Sohag, Egypt; Chemistry and
c
Environmental Division, Manchester Metropolitan University, Manchester, England; Chemistry
Department, Faculty of Science, Minia University, El-Minia, Egypt
ABSTRACT
ARTICLE HISTORY
The novel oxonine 2, 4 have been synthesized by the reaction of
Received 9 July 2019
1
2
2
,3-indandione
with
4-bromo-2-hydroxybenzaldehyde
and/or
-hydroxy-1-naphthaldehyde in the presence of 1,3-diaminopropan-
-ol as green basic catalyst. On the other hand, the reaction of 1,3-
KEYWORDS
1
,3-Indandione; 2-hydroxy
cyclohexanediones with 2-hydroxy aromatic aldehydes under the
same reaction condition afforded xanthenone derivatives 9-11.
aromatic aldehyde; oxonine;
tetrahydroxanthenones;
xanthenones
GRAPHICAL ABSTRACT
X
O
CHO
OH
CH
3
O
O
O
O
X
N
CHO
OH
O
H
3
C
O
O
N
Cyanoguanidine
O
TRIZMA
OH
O
H
3
C
CH
3
Introduction
Reports on the synthesis of oxonine derivatives are quite rare due to their infrequent
occurrence and because of the challenges associated with their stereoselective assem-
[
1]
bly. Hence, the creation of new method for the synthesis of new oxonenes, which is
[
2–4]
present in marine natural products
from available material is an important goal of
[
5]
synthetic chemists. On the other hand, xanthenes exhibit a range of important bio-
logical activities such as anti-inflammatory,
[
6]
[7]
[8]
anti-viral,
anti-bacterial,
anti-
[
9,10]
[11]
[12]
cancer
antileukemic,
and antimalarial
and fluorescent materials for visualization of biomolecules.
properties. Moreover, they are being
[
13]
[14]
used as laser dyes
Xanthenones, especially tetrahydroxanthenones, are also an important class of com-
pounds for their distinct structural features and a great potential for further
CONTACT Amer A. Amer
amer_chem@yahoo.com
Department of Chemistry, Faculty of Science, Sohag
University, Sohag, Egypt
Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/lsyc.
Supplemental data for this article can be accessed on the publisher’s website
ß 2019 Taylor & Francis Group, LLC

2
A. A. ABDELHAMID ET AL.
[
15,16]
transformations.
Therefore, the development of new practical methods to construct
oxonine or xanthenone derivatives is of great importance.
Results and discussion
Herein, we present a new, mild, efficient, and facile method for the synthesis of new oxo-
nines and we discuss the possible reaction mechanisms for the formation of these products.
As an introductory test, we run a model reaction by refluxing 1,3-indandione (4.0 mmol)
with 4-bromo-2-hydroxybenzaldehyde (1.0 mmol) and 1,3-diaminopropan-2-ol (1.0 mmol)
in ethanol for 6 h that resulted in the production of dibenzo[b,g]indeno-
0 0
[
1 ,2 :3,4]fluoreno[1,2-d]oxonine-5,11,16,21-tetraone (2) in 86% yield instead the expected
product 3 may be due to the very high activity of indandione (as reported in our previous
work for the reaction between 2-hydroxybenzaldehyde and three molecules of indandione in
[
17]
the presence of 1,3-diaminopropan-2-ol as a basic catalyst).
In the same manner, 1,3-
indandione reacts with 2-hydroxy-1-naphthaldehyde under the same reaction condition to
give the corresponding oxonine 4. Also, the same products 2 and 4 had been
separated when we used either (4-aminophenyl)methanol or TRIZMA (tris(hydroxy-
methyl)-aminomethane) as a green Lewis base catalyst instead of 1,3-diaminopropan-2-ol.
In other manner, the reaction of 1,3-indandione (1.0 mmol) with 4-(diethylamino)-2-
hydroxybenzaldehyde (1.0 mmol) and cyanoguanidine (1 mmol) in 60 ml ethanol for 6 h
yielded diethylamino-2-(11-oxo-10H,11H-indeno[1,2-b]chromen-10-yl)-2,3-dihydro-1H-
indene-1,3-dione (5), which did not react with 1,3-indandione to give oxonine 7a. Also,
treatment of 1,3-indandione with salicylaldehyde in the presence of a guanidine hydro-
chloride as a Lewis acid catalyst afforded chromen-10-yl)-2,3-dihydro-1H-indene-1,3-
[
18]
[16]
dione 6.
All attempts failed to convert product 6 to oxonine 7 b
(Scheme 1).
The chemical structures of the newly synthesized products 2–7 were confirmed by their
1
13
spectral (IR, H, C NMR) and elemental analyses data. For example, the IR spectra of 2
showed absorption bands assignable for the four C ¼ O groups at 1762, 1714, 1702,
ꢀ
1
1
1
9
664cm . The H-NMR spectra of 2 illustrated the presence of five signals in the range of
13
.01–7.09ppm characteristic for the aromatic protons. Its C NMR spectrum showed 4 sig-
nals at d 192.02, 190.92, 189.99, 172.22 attributed to four carbonyl carbons and 16 signals
which are assigned to aromatic carbons at d 167.08, 148.19, 136.16, 136.08, 135.99, 134.28,
134.14, 132.17, 131.48, 131.16, 129.00, 128.12, 127.57, 125.04, 123.40, 123.31.
The formation of oxonines 2, 4, 7 and xanthenone 5 were assumed to take place
through a Knoevenagel condensation between 1,3-indandione 1 and 2-hydroxy aromatic
aldehyde to produce arylidene 8, which underwent Michael addition with third mole of
1,3-indandione to give intermediate I, which cyclized through path A to give xanthe-
nones 5, 6 or react with other mole of 1,3-indandione to give intermediate III.
Subsequently, cyclization took place to give intermediate V, which undergoes ring
[
19,20]
expansion
via oxidation to yield oxonine 2, 4, and 7 via path B (Scheme 2).
In a further extension of these optimized reaction conditions, we continued to exam-
ine the substrate scope of the reaction using a range 1,3-cyclohexanedione derivatives to
synthesise other oxonines. We found that reaction between salicylaldehyde derivatives
and 1,3-cyclohexanediones yielded xanthenones 9a–c instead of desired oxonines
(Scheme 3). It is clear from previous data that the formation of oxonine depends on the

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SYNTHETIC COMMUNICATIONS
3
O
O
O
Br
Br
N
R
3
O
O
O
O
O
O
CHO
O
O
O
H
Br
O
CHO
O
RNH
O
H
2
2
4
O
CHO
O
H
CHO
O
O
O
H
O
O
O
1
O
N
CHO
2
O
O
N
RNH2
O
H
RNH
R
OH
6
5
O
O
O
H3
C
C
H3
O
RNH2
RNH2
O
O
O
O
X
X
O
7
a: R = NEt ; 7b: R = H
2
Scheme 1. Synthesis of oxonine and xanthenone derivatives.
activity of 1,3-cyclodiones and the type of catalyst. However, only indandione can react
with salicylaldehydes to give the corresponding oxonine. Also, we found that using mid-
dle base such as;(4-aminophenyl)methanol, TRIZMA or1,3-diaminopropan-2-ol as a
basic catalyst for this reaction leads to the formation of oxonine while using a very
weak basic catalyst such as cyanoguanidine or acidic catalyst as guanidine hydrochloride
afforded xanthenone derivatives.
The structures of the newly synthesized compounds 9a–c were confirmed by their
1
13
spectral IR, H, C NMR and elemental analyses. For example, IR spectrum of com-
ꢀ
1
ꢀ1
pound 9 b exhibited characteristic absorption bands at 3359 cm
(OH); 3032 cm
ꢀ
1
ꢀ1
(
C–H aromatic); 2968 and 2876 cm (C–H aliphatic) and 1640 cm for C ¼ O. Its
1
HNMR spectrum showed singlet signal at d 10.64 ppm for OH, in addition to two
singlet signals at d 7.36 and 7.00 for aromatic protons and other singlet signals at d 5.07
for H-pyran, also it exhibited three multiplet and two singlet signals in aliphatic region
at d 2.89, 2.58, 2.00, 1.06, 0.92 attributed to CH , CH , 2CH , 2 CH , 2 CH , respect-
2
2
2
3
3
1
3
ively. Its C NMR spectrum showed one signal d 197.39 for carbonyl carbon and eight
signals which are assigned to aromatic carbons at d 154.76, 149.33, 136.02, 129.85,

4
A. A. ABDELHAMID ET AL.
Y
O
O
X
O
Y
CHO
OH
O
H
+
8
O
X
O
O
1
Y
Y
Y
X
X
O
O
X
O
O
O
O
OH
OH
OH
O
Path A
Path B
O
O
O
O
5
and 6
I
II
O
O
Y
Y
Y
Y
X
O
X
O
O
X
O
H
O
H
O
+
X
O
H
H
Base
-H
O
O
O
O
- H O
2
H
-
O
O
O
O
O
O
O
O
O
O
V
IV
III
2, 4 and 7
Scheme 2. Reaction mechanism for synthesis of oxonines and xanthenones.
R
R1
R
R1
H
O
H
O
O
O
O
H
O
O
Y
OH
Y
X
R
H N
2
NH2
Z
O
Z
R1
X
9a,b
9
a: R = R = Y = X = H; Z = Cl
1
9b: R = R = CH , X = Br, Y = Cl, Z = H
1 3
9
c: R = H, R = Ph, X = Br, Y = Cl, Z = H
1
Scheme 3. Reaction od salicylaldehyde derivatives with 1,3-cyclohexadiones.
1
4
27.44, 124.13, 112.75, 111.61, in addition to seven signals appears at d 60.80, 48.87,
6.75, 39.08, 32.19, 28.69, 26.67 for sp carbons.
3
Similar to salicylaldehydes 2-hydroxy-1-naphthaldehyde react with 5,5-dimethylcyclohex-
ane-1,3-dione in the presence of 1,3-diaminopropan-2-ol as a basic catalyst to give the corre-
sponding xanthenones 10 (Scheme 4). On the other hand, when we used other primary
aliphatic or aromatic amine as a basic catalyst, the reaction afforded Schiff bases 11 and 12

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SYNTHETIC COMMUNICATIONS
5
OH
N
H C
CH3
3
OH
H N
2
12
H
O
H
3
C
CH
3
H
O
O
O
OH
H C
3
CH
3
O
H
O
O
O
O
OH
CH3
CH3
HO
H N
NH2
2
O
OH
H C
3
CH
10
H N
2
3
OH
O
O
N
11
Scheme 4. Synthesis of Schiff bases and xanthenones from naphthaldehyde.
instead of expected product 10. The chemical structures of the new products 10–12 were
1
13
confirmed by their spectral (IR, H, C NMR) and elemental analyses data.
Complete experimental procedures and characterization data of compounds 2–12 are
given in supplemental material.
Experimental
All commercially available reagents were purchased from Merck, Aldrich, and Fluka
and were used without further purification. Melting points were detected with a Kofler
melting points apparatus and uncorrected. Melting points were detected with a Kofler
melting points apparatus and uncorrected. A SHIMADZU FT-IR-8400s spectrometer
1
13
was used to record IR spectra using KBr pellets. H– and C-NMR spectra (400 MHz
1
3
for 1 H, 100 MHz for C) were observed in DMSO-d on DELTA2-NMR spectrometer
6
(
DELTA2, Manchester Metropolitan University, United Kingdom) with tetramethylsi-
1
3
lane as the internal standard. The C-NMR signals were assigned with the aid of DEPT
35/90 experiments.
1
General procedure for the synthesis of oxonine-5,11,16,21-tetraone
derivatives 2, 4
A reaction mixture of 4 mmol (576 mg) indandione and 2 mmol of aromatic aldehydes
namely: p-bromosalicylaldehyde and 2-hydroxynaphthaldehyde in presence of 1 mmol
of 3-aminopropane-1,2-diol or 1,3-diaminopropan-2-ol as a Lewise base catalyst in
6
0 ml ethanol was refluxed for 6 h. The excess solvent was evaporated under vacuum
and the obtained solid was recrystallized from acetic acid to afford oxonine-5,11,16,21-
tetraone derivatives 2 and 4, respectively.

6
A. A. ABDELHAMID ET AL.
9-Bromo-dibenzo[b,g]indeno[10,20:3,4]fluoreno-[1,2-d]oxonine-5,11,16,21-
tetraone (2)
ꢁ
ꢀ1
1
Yield (86%); mp. 294–295 C; FTIR (cm ) 1762, 1714, 1702, 1664; H NMR (400 MHz,
DMSO-d ) d 9.01 (d, J ¼ 7.2 Hz, 1 H, CHarom), 8.23 (d, J ¼ 8.4 Hz, 1 H, CHarom), 7.87
6
13
(
m, 3H, CHarom), 7.65 (m, 8H, CHarom), 7.09 (m, 2 H, CHarom); C NMR
(
100 MHz, DMSO-d ) d 192.02, 190.92, 189.99, 172.22, 167.08, 148.19, 136.16, 136.08,
6
1
1
35.99, 134.28, 134.14, 132.17, 131.48, 131.16, 129.00, 128.12, 127.57, 125.04, 123.40,
23.31; Anal. Calcd. for C H BrO (583): C, 70.00; H, 2.59. Found: C, 69.96; H, 2.38.
3
4
15
5
Synthesis of 8-diethylamino-2-(11-oxo-10H,11Hindeno[1,2-b]chromen-10-yl)-
,3-dihydro-1H-indene-1,3-dione (5)
2
In 60 ml of ethanol, a mixture of 1 mmol of 4-(diethylamino)-2-hydroxybenzaldehyde
and 2 mmol (292 mg) of 1 H-indene-1,3(2H)-dione has been refluxed in the presence of
a cyanoguanidine as a Lewis base catalyst for 5 h. On cooling, the solid product was col-
lected by filtration, dried under vacuum, and recrystallized from ethanol to give 5.
ꢁ
ꢀ1
1
Yield (75%); mp. 246–247 C; FTIR (cm ) 3423, 3047, 1680, 1623; H NMR
(
1
1
1
400 MHz, DMSO-d ) d 10.82 (s, 1H, OH), 9.23 (d, J ¼ 9.2 Hz, 1 H, CHarom), 8.22 (s,
6
H, CHarom), 7.81–7.42 (m, 8H, CHarom), 6.45 (d, J ¼ 9.4 Hz, 1H, CHarom), 6.19 (s,
13
H, CH-pyran), 1.19–1.04 (m, 10H, 2CH þ2CH ); C NMR (100 MHz, DMSO-d ) d
2
3
6
91.92, 183.62, 163.61, 155.10, 139.66, 136.36, 134.57, 134.29, 121.79, 110.83, 105.50,
9
5.78, 44.56, 12.76; Anal. Calcd. for C H NO (449): C, 77.49; H, 5.16; N, 3.12.
2
9
23
4
Found: C, 77.45; H, 5.17; N, 3.00.
General method for synthesis of xanthen-1-one (9a-c and 10)
A mixture of 1 mmol 2-hydroxyaromaticaldehyde, 2 mmol cyclohexane-1,3-diones and
1
5
mmol either 3-aminopropane-1,2-diol or 1,3-diaminopropan-2-ol as a basic catalyst in
0 ml ethanol was refluxed. The reaction progress was monitored by TLC till comple-
tion after about 6 h. Excess solvent was evaporated under vacuum and the resulted solid
was filtered and recrystallized from ethanol.
7-Chloro-9-(2-hydroxy-6-oxocyclohex-1-en-1-yl)-2,3,4,9-tetrahydro-1H-
xanthen-1-one (9a)
ꢁ
ꢀ1
1
Yield (83%); mp. 251–252 C; FTIR (cm ) 3361, 3020, 2967, 2915, 1632, 1618; H
NMR (400 MHz, DMSO-d ) d 10.73 (br. s, 1H, OH), 7.24 (d, J ¼ 8.8 Hz, 1 H, CHarom),
6
7
.02 (s, 1H, CHarom), 6.92 (d, J ¼ 8.4 Hz, 1H, CHarom), 5.02 (s, 1H, CH-pyran), 2.46
13
(m, 4H, 2CH ), 2.20 (m, 4H, 2CH ), 1.79 (m, 4H, 2CH ); C NMR (100 MHz, DMSO-
2 2 2
d6) d 197.82, 167.84, 149.87, 134.10, 131.05, 130.26, 129.07, 126.30, 123.98, 118.22,
1
14.57, 112.09, 40.48, 37.13, 27.64, 20.87; Anal. Calcd. for C H ClO (344.5): C, 66.19;
19 17 4
H, 4.97. Found: C, 66.29; H, 4.95.

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SYNTHETIC COMMUNICATIONS
7
General method for synthesis of Schiff bases 11 and 12
A mixture of 1 mmol 2-hydroxynaphthaldehyde, 2 mmol 5,5-dimethylcyclohexane-1,3-
dione and 1 mmol either 1-aminopropan-1-ol or 1-(3-aminophenyl)ethanol as a basic
catalyst in 60 ml ethanol was refluxed for 6 h. Excess solvent was evaporated under vac-
uum and the resulted solid was filtered, washed with cold ethanol, and recrystallized
from ethanol to give 11 or 12, respectively.
1-(1-hydroxypropyl)iminomethyl-2-naphthol (11)
ꢁ
ꢀ1
1
Yield (91%); mp. 107 C; FTIR (cm ) 3418, 3245, 3027, 2967, 2892, 1625; H NMR
400 MHz, DMSO-d ) d 9.02 (s, 1H, CH ¼ N), 8.03 (m, 1H, CHarom), 7.69 (m, 2H,
(
6
CHarom), 7.43 (m, 1 H, CHarom), 7.19 (m, 1H, CHarom), 6.70 (m, 1H, CHarom), 5.00
s, 1H, OH), 3.86 (m, 1H, CHaliphatic), 3.92 (m, 1H, CHaliphatic), 3.46 (m, 2H,
(
1
3
OH þ CHaliphatic), 1.12 (s, 3H, CH ); C NMR (100 MHz, DMSO-d ) d 178.97,
3
6
1
59.80, 137.71, 135.06, 129.39, 128.38, 126.60. 122.48, 118.75, 105.92, 65.83, 58.05, 21.34;
Anal. Calcd. for C H NO (229): C, 73.34; H, 6.59; N, 6.11. Found: C, 73.41; H, 6.50;
1
4
15
2
N, 6.04.
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