Synthesis and photochemical properties of 3,6-di-tert-butyl-9H-carbazole derivatives

Article abstract of DOI:10.1134/S1070363215060122

Method of synthesis has been developed for a series of 3,6-di-tert-butyl-9H-carbazole derivatives and their photochemical properties have been investigated. The dependence of the Steglich esterification reaction on the nature of the catalyst was studied. The synthesized compounds show fluorescent emission in the range 400-600 nm with a high quantum yield.

Full text of DOI:10.1134/S1070363215060122

ISSN 1070-3632, Russian Journal of General Chemistry, 2015, Vol. 85, No. 6, pp. 1431–1439. © Pleiades Publishing, Ltd., 2015.
Original Russian Text © M.S. Gruzdev, U.V. Chervonova, E.A. Venediktov, E.P. Rozhkova, A.M. Kolker, E.A. Mazaev, N.A. Dudina, N.E. Domracheva,
2
015, published in Zhurnal Obshchei Khimii, 2015, Vol. 85, No. 6, pp. 964–972.
Synthesis and Photochemical Properties
of 3,6-Di-tert-butyl-9H-carbazole Derivatives
a
a
a
a
a
M. S. Gruzdev , U. V. Chervonova , E. A. Venediktov , E. P. Rozhkova , A. M. Kolker ,
b
a
c
E. A. Mazaev , N. A. Dudina , and N. E. Domracheva
a
Krestov Institute of Solution Chemistry, Russian Academy of Sciences,
ul. Akademicheskaya 1, Ivanovo, 153045 Russia
e-mail: gms@isc-ras.ru
b
Ivanovo State University of Chemistry and Technology, Ivanovo, Russia
c
Kazan Physico-Technical Institute, Kazan Scientific Center, Russian Academy of Sciences, Kazan, Tatarstan, Russia
Received January 12, 2015
Abstract—Method of synthesis has been developed for a series of 3,6-di-tert-butyl-9Н-carbazole derivatives
and their photochemical properties have been investigated. The dependence of the Steglich esterification
reaction on the nature of the catalyst was studied. The synthesized compounds show fluorescent emission in the
range 400–600 nm with a high quantum yield.
Keywords: carbazole, Steglich esterification, luminophores, fluorescent emission, Stokes shift
DOI: 10.1134/S1070363215060122
One of promising directions in modern organic
dehyde by the Sonogashira reaction of 3,6-di-tert-
butyl-9-(4-ethynylphenyl)-carbazole with 4-(4'-bromo-
benzoyloxy)-2-hydroxybenzaldehyde. 3,6-Di-tert-butyl-
9-(4-ethynylphenyl)carbazol (IV) was prepared by the
reaction of 3,6-di-tert-butyl-9-(4'-iodophenyl)carbazol
(II) with trimethylethynylsilane under the Sonogashira
reaction conditions with subsequent elimination of the
trimethylsilyl group by the action of tetrabutylammo-
nium fluoride (TBAF) (Scheme 1).
chemistry and material science is the creation of
organic light-emitting diods (OLEDs), including those
on the basis of luminophores [1]. In this sense
carbazole and its derivatives are of great interest, and
they are actively studied due to their use in material
science, coordination chemistry, pharmacy, etc. [2–6].
Thus, carbazole derivatives are used as synthons for
preparation of luminophores [7], and branched 3,6-
disubstituted derivatives of carbazole are applied as
building blocks for creation of more complex organic
molecules [8]. Compounds of this type are now used
for the synthesis of OLEDs because of their high hole
conductivity, photochemical stability, and electro-
conductivity [9–11]. The carbazole-based dendrites are
shown to act as luminescent gelators for ordered
organogels [16, 17].
It turned out that the reaction of 3,6-di-tert-butyl-9-
(4-ethynylphenyl)carbazol (IV) with 4-(4'-bromo-
benzoyloxy)-2-hydroxybenzaldehyde (V) under the
Sonogashira reaction conditions does not lead to the
expected products of condensation irrespective of the
temperature, reaction time, solvent, sequence of
mixing of the reagents. Replacement of aldehyde V by
4
-(4'-iodobenzoyloxy)-2-hydroxybenzaldehyde did not
lead to the desired result, either. The only isolated
product was the product of elimination of the ethynyl
group from the starting carbazol IV, 3,6-di-tert-butyl-
The goal of the present work was the synthesis of
linear esters of the carbazole series with active
functional group in the focal point, which can further
act as a basis for the formation of azomethine ligands
in the reaction of complex formation [14, 15]. First, we
intended to synthesize 4-[3,6-di-tert-butyl-9-(4-ethynyl-
phenyl)-carbazol-9-yl]benzoyloxy-2-hydroxybenzal-
9-phenylcarbazole (VI) (Scheme 2).
Product VI was isolated in 75% yield by chro-
matography. Its structure was proved by mass
1
spectrometry and H NMR spectroscopy as well as by
1
431

1
432
GRUZDEV et al.
Scheme 1.
а
b
NH
NH
N
I
I
II
CH3
c
d
N
C
C
Si CH3
CH3
N
C
CH
III
; b, С
IV
Cl
3
а, AlCl , t-BuCl, CH
Cl
2 2
6
Н
4
I
2
, Cu
2
O, dimethylacetamide; c, [Pd(PPh
3
)
2
2
3 3 3
], CuI, (CH ) SiC≡CH, Et N, THF;
d, TBAF, ТHF.
Scheme 2.
N
C
C
H
N
H
VI
3 2 2 3
V, [Pd(PPh ) Cl ], CuI, Et N, THF.
elemental analysis. The formation of VI can be ex-
plained by the fact that Pd(0) particles are not formed
due to the presence of a polar group (HC=O, OH,
COO) in one of the substrates, and, as a result, the
rupture of the Ph–C bond.
(VII). The yield of compound VII was ~80% and
increased to 91% when small amount of 18-crown-6
was added.
Esterification of acid VIII with 4-hydroxysalicylic
aldehyde by Steglich reaction [16] in the presence of
dicyclohexylcarbodiimide (DCC) and catalytic amounts
of dimethylaminopyridine (DMAP) or its salts leads to
the formation of aldehyde IX. The structure and purity
of the products was proved by the methods of IR and
In view of this, an alternative approach was chosen
for the synthesis of 3,6-disubstituted carbazoles with
the aldehyde group in the focal point, by esterification
of 3,6-di-tert-butylcarbazol-9-ylbenzoic acid (VIII)
with 4-hydroxysalicyl aldehyde.
1
13
Н, С NMR spectroscopy, mass spectrometry, chro-
matography and the data of elemental analysis
Acid VIII was prepared by the Ullmann reaction
from compound I and methyl 4-iodobenzoate in
dimethylacetamide with subsequent hydrolysis of the
formed 3,6-di-tert-butyl-9-(4'-methoxycarbonyl)carbazole
(
Scheme 3).
When esterification of acid VIII by Steglich was
performed in CH Cl –DMF (99 : 1) solution, in the
2
2
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SYNTHESIS AND PHOTOCHEMICAL PROPERTIES
1433
Scheme 3.
O
O
а
I + I
N
C
O CH3
O
CH3
VII
O
O
b, c
d
N
C
N
C
O
H
OH
O
C
OH
VIII
O, dimethylacetamide; b, NaOH, EtOH; c, HCl, H
IX
2 2
O; d, 4-hydroxysalicyl aldehyde , DCC, DMAP, СH Cl .
а, Cu
2
2
Scheme 4.
O
O
O
O
−
N
N
N
C
+
N C N
N
C
H
H
N
N
H
+
O
OH
O
HN
O
HN
H+
N
−
N
O
H+
O
O
N
−
N
O
O
H
OH
B
А
HN
HN
O
O
+
N
O
O
H
OH
IX
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GRUZDEV et al.
Scheme 5.
O
HN
N
R
+
HN
N
+
O
H
−
SO3
H
H
А
O
O
O
HO
R
O
O
R
H
+
N
+
N
N
O
OH
H
N
N+
OH
IX
R =
N
first step a stable О-acylisourea intermediate is formed
17], which only partly enters further reaction with the
ester” [18]. Under the conditions of the studied
reaction this does not occur due to insufficient
nucleophilic ability of the reaction catalyst (the organic
base) to accept and to donate the proton of the carboxy
group [19, 20]. In order to increase the yield of the
reaction product IX we have performed the
esterification of acid VIII by Steglich reaction in the
presence of various catalysts (Table 1).
[
phenol group of the aldehyde in the presence of
dimethylaminopyridine catalyst, giving rise to
aldehyde IX in as low as 10–15% yield. To optimize
this stage, we have performed step-by-step analysis of
the intermediates of the reaction and isolated the most
stable of them (Scheme 4).
The highest yield of the reaction product was
achieved using 4-dimethylaminopyridinium p-tosylate.
Apparently, this can be attributed to a higher catalytic
activity due to the protonation of the pyridine nitrogen
and the ability to participate in the attack of the О-
acylisourea adduct (A) acting as the acyl group carrier
Thus, by the method of column chromatography the
О-acylisourea intermediate (A) was separated and
characterized by the data of NMR spectroscopy and
mass spectrometry (Fig. 1). Besides, intermediate B
was chromatographically isolated and characterized by
1
the method of H NMR spectroscopy (Fig. 2).
(
Scheme 5).
The formation of intermediate A and its partial
involvement in further reaction governs the yield of the
target product. As a rule, 4-dimethylaminopyridine is a
stronger nucleophile as compared with hydroxyl-
containing compounds, and reacts with the О-
acylisourea intermediate to form the so-called “active
In the second stage of our work we have studied the
photochemical properties of the synthesized deriva-
tives of 3,6-di-tert-butyl-9H-carbazol (III, IV, VII–IX).
The data on electron absorption spectra of
compounds III, IV, VII–IX are presented in Table 2.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 85 No. 6 2015

SYNTHESIS AND PHOTOCHEMICAL PROPERTIES
1435
(
a)
(
b)
8
.5
8.0
7.5
7.0
6.5
6.0
6.5
m/z
δ, ppm
1
Fig. 1. (a) H NMR spectrum and (b) fragment of mass-spectrum of О-acylisourea adduct (A).
2
CH -cyclo
2
CH -cyclo
δ, ppm
δ, ppm
1
Fig. 2. H NMR spectrum of intermediate B.
The investigated compounds show bright fluorescence.
does not depend on the wavelength of the exciting light.
This is indicative of the fact that the observed fluore-
scence is connected with the nature of the studied
object. A similar result was obtained for other compounds.
For example, in Fig. 3 the electronic spectrum of fluore-
scence and excitation/fluorescence of compound VII is
shown. As can be seen, the spectrum of fluorescence
Table 1. Conditions of the Steglich esterification and the yield of product VIII (10 mol% of catalyst, 14 h)
Catalyst
-Dimethylaminopyridine
-Dimethylaminopyridine 4-tosylate
Solvent
Yield of aldehyde IX, %
4
4
CH
CH
CH
CH
CH
2
2
2
2
2
Cl
2
Cl
2
Cl
2
Cl
2
Cl
2
–DMF, 99 : 1
13
87
5
p-Aminopyridine
–DMF, 99 : 1
–DMF, 99 : 1
4
4
-Pyrrolidinopyridine
27
20
-Pyrrolidinopyridine 4-tosylate
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 85 No. 6 2015

1
436
GRUZDEV et al.
I
I
1
→3
λ, nm
λ, nm
Fig. 3. Normalized absorption spectra of (1) electron
absorption, (2) fluorescence, and (3) fluorescence
excitation of compound VI in CH Cl .
2 2
Fig. 4. Normalized fluorescence spectra of compounds VI–
VIII (1→3) in CH Cl .
2
2
The band in the fluorescence spectra of compounds
quenching of the excited singlet states of the studied
molecules.
III, VII–IX suffers a red shift, and its value is
increased in the order III < VII < VIII < IX. The same
is true for the Stokes shift (Fig. 4).
Taking into account the nature of the functional
groups, the decrease in the luminescent activity of the
studied compounds may be connected with the
decrease in the π-electron density on the carbazole
moiety and the participation in nonradiative decay
processes of the excited singlet molecules with
intramolecular charge transfer.
This may be due to the increase in the dipole
moment of the studied molecules in the excited singlet
state [21]. As follows from the data of Table 2, the
functionalization of the carbazole leads to a decrease in
the quantum yield of fluorescence and its lifetime.
These data point to a high probability of nonadiative
EXPERIMENTAL
Table 2. Spectral luminescent parameters of compounds III,
IV, VII–IX
IR spectra were taken on a Bruker Vertex 80
instrument in the range 7500–350 cm in KBr. Н and
С NMR spectra were taken on a Bruker 500
a
–
1
1
1
3
0
-0
Comp.
no.
λ
fl
,
max
λ
abs , nm
τfl, ns
φ
fl
(500.13 MHz) spectrometer in CDCl with TMS as an
3
nm
internal reference. Thin layer chromatography was
carried out on RoTH UV 254 plates, development
under UV lamp with λ = 254–310 nm. Elemental
analysis was performed on a FlashEA 1112 analyzer.
Mass spectra were registered on instruments JMS-700
JEOL (FAB) and JMS-100GCV JEOL (EI). The
spectra of absorption, fluorescence and excitation/
fluorescence were recorded on a SOLAR CM2203
spectrofluorimeter.
III
~250 sh, ~287 sh, 298, 398
7.1 0.71
~
~
316 sh, 325, ~332 sh,
343 sh
b
IV
320.5, 295, 259
237, 258 sh, 287, 296, 446
320 sh, 335, 345
238, ~260 sh, ~288 sh, 459
96, 336 sh, 345
240, ~259 sh, 288, 295, 491
379
6.3 0.09
9.3 0.49
VII
VIII
IX
~
9.4 0.39
6.3 0.11
2
The quantum yield of fluorescence (φ ) was
fl
determined by the relative method using quinine
bisulfate in 0.1N H SO as a standard [22], according
2
4
~336 sh, 347
to formula (1).
а
b
Solvent is CH
2
Cl
2
. Data of [8].
2
2
φ
fl = φst(АstSn )/(АSst
n
st).
(1)
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SYNTHESIS AND PHOTOCHEMICAL PROPERTIES
1437
where φ = 0.55 [23]; S and S denote areas under the
fluorescence curves of the sample and the standard; А
3,6-Di-tert-butyl-9-(4'-iodophenyl)carbazole (II).
The mixture of 3,6-di-tert-butyl-9H-carbazole (1 g,
3.58 mmol), p-diiodobenzene (3.54 g, 10.8 mmol),
st
st
and А denote the absorption of the sample and the
st
standard at the length of the exciting light (0.13 at
potassium carbonate (1 g, 7.2 mmol) and Cu O
2
λexc = 326 nm); n and n denote the refraction indices
(0.25 g) was heated for 12 h in dimethylacetamide
(60 mL) at 165°С. Then the reaction mixture was
cooled, 100 mL of CH Cl was added, filtered, washed
st
of the used solvents equal to 1.42 (CH Cl ) and 1.33
2
2
(
H O). The kinetics of quenching of fluorescence was
2
2
2
measured on a laser pulse fluorimeter LIF-200. As the
source of the laser exciting light ILGI-503 (λexc
37.1 nm) was used. The lifetime of the fluorescence
τfl) was calculated by formula (2).
thrice with water, the solvent was removed, the residue
was chromatographed on silica gel, eluent hexane–di-
chloromethane (99 : 1). The product was crystallized
from the mixture toluene/ethanol to obtain white
crystalline powder. Yield 1.37 (80 %), mp 174ºC. IR
=
3
(
2
2
2
p
τ
fl = τ – τ
,
(2)
–
1
spectrum, ν, cm : 3064 (Ph–H), 2962–2866 (CH ),
3
1
where τ denotes the observed lifetime of fluorescence,
τp is the lifetime of the laser pulse [23]. All
measurements were performed in square quartz cells 1
cm thick at room temperature (22ºС) in the presence of
air oxygen.
5
95, 500 (PhC–I). H NMR spectrum, δ, ppm: 8.05 d
(2Н, Ar-H); 7.81 d (2Н, Ar-H); 7.38 d (2H, Ar-H);
1
3
7
.24 d (4H, Ph-H); 1.38 s (18H, CH3). C NMR
spectrum, δ, ppm: 143.2, 138.9, 138.8, 138.0, 128.5,
23.7, 123.5, 116.3, 109.0, 34.7, 91.3, 32.0. Mass
1
+
+
spectrum, m/z: 482 [M – H] , 426 [M – tert-butyl] ,
54 [M – I] . Found, %: C 64.80; Н 5.94; N 2.86.
4
-Dimethylaminopyridinium p-tosylate [24, 25]
+
3
was prepared by stirring equimolar amounts of dimethyl-
aminopyridine and toluenesulfonic acid monohydrate
in dry tetrahydrofurane in the course of 1 h. The
formed precipitate was filtered off and dried in a
vacuum.
C H NI. Calculated, %: C 64.87; Н 5.86; N 2.91.
2
6
28
3,6-Di-tert-butyl-9-[(4-trimethylsilyl)ethynyl]-
phenylcarbazole (III). To the mixture of 3,6-di-tert-
butyl-9-(4'-iodophenyl)carbazole (2.02 g, 9.22 mmol),
bis(triphenylphosphine)palladium(II) chloride (129 mg,
Similarly, 4-pyrrolidinopyridinium p-tosylate was
obtained.
0
.184 mmol), CuI (9 mg, 0.047 mmol), and 20 mL of
dry triethylamine trimethylsilylacetylene (1.6 mL,
1.3 mmol) was added, the reaction mixture was
stirred for 8 h at 60°С, cooled, CH Cl was added, and
1
3
,6-Di-tert-butyl-9Н-carbazole (I). Carbazole
2
2
(
5.0 g, 0.03 mol) was dissolved in 100 mL of CH Cl ,
2
2
the solvents were removed in a vacuum, the residue
was chromatographed on silica gel, eluent hexane–
CH Cl (9 : 1), to obtain light-yellow solid. Yield 1.07 g
cooled to 0°С, and slowly added the solution of 2-
chloro-2-methylpropane (6.6 mL, 0.06 mol) in 20 mL
of CH Cl . AlCl (4.0 g, 0.03 mol) was introduced in
2
2
2
2
3
–1
(
2
85 %), mp 208ºC. IR spectrum, ν, cm : 3050 (Ph-H),
962–2862 (CH ), 2156 (C≡C), 866-841 (SiМе ). H
small portions in the course of 1 h with constant
stirring, and the reaction mixture was stirred for 8 h at
room temperature. Then the flask was cooled with ice,
1
3
3
NMR spectrum, δ, ppm: 8.04 d (2H, Ar-H), 7.57 d
2Н, Ph-H), 7.40 d (2Н, Ar-H), 7.35 d (2H, Ph-H),
.25 d (2H, Ar-H), 1.36 s (18H, CH ), 0.20 s (9Н,
(
3
00 mL of water was added in small portions at
7
3
stirring, the mixture was poured in 500 mL of water,
extracted with CH Cl (7 × 100 mL). The organic layer
13
SiMe3). С NMR spectrum, δ, ppm: 143.2, 138.8,
2
2
1
1
38.3, 133.4, 126.2, 123.7, 123.6, 121.5, 116.3, 109.2,
was washed with water, dried over Na SO , the solvent
2
4
04.4, 95.1, 34.7, 32.0, 1.1. Mass spectrum, m/z: 251.1
was removed on a rotary evaporator. The residue was
thrice crystallized from hexane to give white
crystalline powder. Yield 4.5 g (54 %), mp 229–231ºC.
+
+
[M] , 436.4 [M – CH ] . Found, %: С 82.25; Н 7.95; N
3
3
3
.23. C H NSi. Calculated, %: С 82.42; Н 8.19; N
31 37
.10.
–
1
IR spectrum, ν, cm : 3414 (NH), 3064 (Ph–H), 2960–
1
2
862 (CH ). H NMR spectrum, δ, ppm: 8.07 s (2H,
3,6-Di-tert-butyl-9-(4-ethynylphenyl)carbazole
3
Ar–H), 7.84 s (1Н, NH), 7.46 d (2H, Ar–H), 7.32 d
(IV). To the solution of 3,6-di-tert-butyl-9-[(4-trimethyl-
silyl)ethynyl]phenylcarbazole (1.00 g, 2.2 mmol) in
THF (10 mL) tetrabutylammonium fluoride (2.88 g,
11 mmol) was added. The reaction mixture was stirred
in the dark for 5 min at room temperature in an argon
atmosphere, the solution was passed through the
1
3
(
2Н, Ar–H), 1.45 s (18Н, –CH ). C NMR spectrum,
3
δ, ppm: 143.2, 138.0, 123.5, 123.3, 116.1, 110.0, 34.7,
+
3
2.1. Mass spectrum, m/z: 279.19 [M] . Found, %: C
8
5.25; H 9.89; N 6.16. C H N. Calculated, %: C 85.97; H
2
0 25
9.02; N 5.01.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 85 No. 6 2015

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GRUZDEV et al.
+
column packed with silica gel, the filtrate evaporated
in a vacuum to obtain light-yellow solid. Yield 0.60 g
m/z: 355.2 [M] . Found, %: С 88.15; Н 7.98; N 3.87.
C H N. Calculated, %: С 87.84; Н 8.22; N 3.94.
3
1
37
–
1
(
(
98 %), mp 135ºC. IR spectrum, ν, cm : 3255
1
3,6-Di-tert-butyl-9-(4-methoxycarbonyl)carbazole
VII) was prepared similarly to compound II from 3,6-
di-tert-butyl-9H-carbazole (3.5 g, 13.0 mmol), 1-iodo-
-methylbenzoate (3.73 g, 14.23 mmol), Cu O (3.73 g,
26.0 mmol), reaction time 24 h. The product was
isolated by column chromatography, eluent hexane–
ethyl acetate (10 : 1). Yield 4.3 g (80 %), mp 156ºC.
RC≡CH), 3045 (Ph-H), 2964–2862 (CH ). H NMR
3
(
spectrum, δ, ppm: 8.14 d (2H, Ar-H), 7.7 m (2Н,
Ar-H), 7.54 m (2Н, Ar-H), 7.47 d (2H, Ph-H), 7.37 d
4
2
(
2H, Ph-H), 3.17 m (1H, C≡CH), 1.47 s (18H, –CH3).
С NMR spectrum, δ, ppm: 143.2, 138.8, 138.6,
1
3
1
7
33.6, 126.3, 123.7, 123.6, 120.4, 116.3, 109.1, 83.0,
+
7.9, 34.7, 32.0. Mass spectrum, m/z: 379.1 [M] , 364
–
1
+
IR spectrum, ν, cm : 3059 (Ph-H), 2957–2862 (CH ),
3
[M – CH ] . Found, %: С 88.47; Н 7.99; N 3.67.
3
1
1
749 (–COO–). H NMR spectrum, δ, ppm: 8.14 s
2H, Ar-H), 7.43 m (4H, Ph-H), 7.25 d (2H, Ar-H),
.09 d (2H, Ar-H), 3.89 s (3H, –COOCH ), 1.46 s
18H, CH ). С NMR spectrum, δ, ppm: 158.6, 142.5,
139.8, 130.8, 128.3, 123.5, 123.1, 116.2, 115.0, 109.1,
5.6, 34.8, 32.1. Mass spectrum, m/z: 414.3 [M – Н] ;
calculated 413.5. Found, %: С 80.79; Н 7.03; N 3.60; O
.58. С Н NO . Calculated, %: С 81.32; Н 7.56; N
28 31 2
C H N. Calculated, %: С 88.61; Н 7.7; N 3.69.
2
8
29
(
4
-(4'-Bromobenzoyloxy)-2-hydroxybenzaldehyde
7
(
3
13
(
V). 4-Bromobenzoic acid (5 g, 25 mmol) was dis-
3
solved in the mixture of CH Cl and DMF, 2,4-
2
2
+
dihydroxybenzaldehyde (3.45 g, 25 mmol) was added
and after 10 min dicyclohexylcarbodiimide (5.78 g,
5
2
8 mmol) and catalytic amount of dimethylamino-
8
3
pyridine, the reaction mixture was stirred for 12 h at
room temperature. The formed precipitate was filtered
off, the filtrate was successively washed with 5%
acetic acid (2 × 25 mL), 5% cold solution of NaOH
.39; O 7.74.
4
-(3,6-Di-tert-butylcarbazol-9-yl)benzoic
VIII). The mixture of 3,6-di-tert-butyl-9-(4-methoxy-
acid
(
carbonyl)carbazole (2.5 g, 6.0 mmol), 50 mL of
ethanol, and 20 mL of 1 М solution of NaOH was
stirred under reflux for 10 h, cooled to room
temperature, poured into 100 mL of distilled water and
acidified by adding 40 mL of 1 М HCl. The crude
product was separated by filtration, chromatographed
on silica gel, eluent hexane–ethyl acetate (1 : 1), to
obtain the product as fine white powder. Yield 2.2 g
(
2 × 25 mL) and water (3 × 25 mL), dried over
anhydrous Na SO . The solvent was distilled off on a
rotary evaporator, yellowish solid residue was
chromatographed on silica gel, eluent CНCl . Yield
2
(
1
spectrum, δ, ppm: 11.19 s (1H, OH), 9.82 s (1H,
CНO), 7.97 d (2H, Ph-H), 7.61 d (2H, Ph-H), 7.57 d
(
ppm: 195.5, 163.2, 157.4, 152.2, 135.0, 132.2, 131.8,
1
3
2
4
3
–
1
.57 g (53.4 %), mp 187ºC. IR spectrum, ν, cm : 3215
OH), 3067 (Ph-H), 2926 (CHO), 1735 (–COO–),
1
673 (CHO), 1268 (С–O), 678. 625 (С–Br). H NMR
–
1
(
3
(
92 %), mp 287ºC. IR spectrum, ν, cm : 3414 (OH),
000 (Ph-H), 2959–2866 (CH ), 1688 (C=O), 1604
1
3
1H, Ph-H), 6.83 m (2H, Ph-H). С NMR spectrum, δ,
3
1
Ph-H), 1471 (CH ), 1289 (С–N). H NMR spectrum,
3
δ, ppm: 8.52 s (1H, OH), 8.36 d (2H, Ar-H), 8.15 s
29.4, 127.8, 118.9, 113.9, 110.8. Mass spectrum, m/z:
+
(
2H, Ar-H), 7.73 d (2H, Ar-H), 7.47 m (4H, Ph-H),
21 [M] ; calculated 321.1. Found, %: С 52.69; Н 2.92;
1
3
1
1
1
.47 s (18H, CH ). С NMR spectrum, δ, ppm: 171.2,
O 19.00; Br 25.38. С Н BrО . Calculated, %: С 52.36;
Н 2.82; O 19.93; Br 24.9.
3
1
4
9
4
43.7, 143.4, 138.4, 132.0, 127.0, 125.8, 123.9, 116.4,
10.0, 109.3, 34.8, 31.9. Mass spectrum, m/z: 399.4
3
,6-Di-tert-butyl-9-phenylcarbazole (VI) was pre-
+
[
M] ; calculated 399.2. Found, %: С 81.27; Н 7.15; N
pared similarly to compound II from 4-(4'-bromo-
benzoyloxy)-2-hydroxybenzaldehyde (0.42 g, 1.32 mmol),
bis(triphenylphosphine)palladium (II) chloride (129 mg,
3
7
.24; O 8.34. С Н NO . Calculated, %: С 81.17; Н
27 29 2
.32; N 3.51; O 8.01.
4-(3,6-Di-tert-butylcarbazol-9-yl)benzoyloxy-2-
0
.184 mmol), CuI (9 mg, 0.047 mmol), 20 mL of
trimethylamine, and 3,6-di-tert-butyl-9-(4-ethynyl-
hydroxybenzaldehyde (IX). 4-(3,6-Di-tert-butyl-9H-
carbazol-9-yl)benzoic acid (1.5 g, 3.8 mmol) was dis-
solved in CH Cl , 2,4-dihydroxybenzaldehyde (0.53 g,
3.8 mmol), the calculated amount of dicyclo-
hexylcarbodiimide (0.78 g, 3.8 mmol), and a catalytic
amount of dimethylaminopyridine tosylate was added,
and the mixture was stirred at room temperature for
14 h. The formed precipitate was filtered off, the
phenyl)carbazole (0.5 g, 1.32 mmol). Yield 0.6 g
–
1
(
2
75%), mp 186ºC. IR spectrum, ν, cm : 3050 (Ph-H),
2
2
1
962–2862 (CH ). H NMR spectrum, δ, ppm: 8.35 d
3
(
2H, Ar-H), 8.15 s (2Н, Ph-H), 7.75 d (2Н, Ar-H), 7.49
d (2H, Ph-H), 7.28 s (1H, Ar-H), 1.36 s (18H, CH ).
3
1
3
С NMR spectrum, δ, ppm: 151.2, 138.6, 128.2,
1
27.1, 123.5, 121.5, 117.4, 36.4, 31.4. Mass spectrum,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 85 No. 6 2015

SYNTHESIS AND PHOTOCHEMICAL PROPERTIES
1439
filtrate was successively washed with 5% acetic acid
2 × 25 mL), 5% solution of cold NaOH (2 × 25 mL)
and water (3 × 25 mL), dried over anhydrous Na SO .
The solvent was removed, the solid residue was
chromatographed on silica gel, eluent hexane–CHCl3
Dehaen, W., J. Org. Chem., 2006, vol. 71, no. 8,
p. 2987. DOI: 10.1021/jo052534u.
8. Zhu, Z. and Moore, J.S., J. Org. Chem., 2000, vol. 65,
no. 1, p. 116. DOI: 10.1021/jo991167h.
. Liu, Y., Di, C., Xin, Y., Yu, G., Liu, Y., He, Q., Bai, F.,
Xu, S., and Cao, S., Synt. Met., 2006, vol. 156, nos. 11–
(
2
4
9
(
1 : 1), to obtain the product as fine powder of light-
1
3, p. 824. DOI: 10.1016/j.synthmet.2006.04.011.
yellow color. Yield 1.48 g (87 %), mp 246ºC. IR
–
1
1
1
0. Moss, K.C., Bourdakos, K.N., Bhalla, V., Kamtekar, K.T.,
Bryce, M.R., Fox, M.A., Vaughan, H.L., Dias, F.B., and
Monkman, A.P., J. Org. Chem., 2010, vol. 75, no. 20,
p. 6771. DOI: 10.1021/jo100898a.
1. Thongkasee, P., Thangthong, A., Janthasing, N., Sudyo-
adsuk, T., Namuangruk, S., Keawin, T., Jungsuttiwong, S.,
and Promarak, V., Appl. Mater. Interf., 2014, vol. 6,
no. 11, p. 8212. DOI: 10.1021/am500947k.
spectrum, ν, cm : 3062 (Ph-H), 29566–2863 (CH ),
1
3
1
742 (–COO–), 1658 (CHO), 1253 (С–N). H NMR
spectrum, δ, ppm: 11.29 s (1H, OH), 9.88 s (1H,
COH), 8.39 d (2H, Ar-H), 8.15 s (2H, Ar-H), 7.77 d
(
2H, Ar-H), 7.63 d (1H, Ar-H), 7.47 m (4H, Ar-H),
6
–
1
1
.97 s (1H, Ar-H), 6.94 m (1H, Ar-H), 1.47 t (18H,
13
CH ). С NMR spectrum, δ, ppm: 195.5, 163.5, 163.2,
3
57.5, 143.8, 143.6, 138.3, 135.0, 132.0, 126.3, 125.9,
1
1
2. Yang, X., Lu, R., Xu, T., Xue, P., Liu, X., and Zhao, Y.,
23.9, 118.7, 116.4, 114.0, 110.8, 109.2, 34.7, 31.9.
Chem. Commun., 2008, p. 453. DOI: 10.1039/B713734F.
+
Mass spectrum, m/z: 520.6 [M – Н] ; calculated 519.6.
3. Yang, X., Lu, R., Gai, F., Xue, P., and Zhan, Y., Chem.
Commun., 2010, vol. 46, p. 1088. DOI: 10.1039/
B918986F.
Found, %: С 77.85; Н 6.59; N 2.13; O 13.4. С Н NO .
3
4
33
4
Calculated, %: С 78.59; Н 6.40; N 2.70; O 12.32.
1
1
4. Chervonova, U.V., Gruzdev, M.S., and Kolker, A.M.,
ACKNOWLEDGMENTS
Russ. J. Gen. Chem., 2011, vol. 81, no. 9, p. 1853. DOI:
1
0.1134/S1070363211090192.
This work was supported by the grant of The
President of the Russian Federation (no. MK-
0.2014.3), grant of Russian Foundation for Basic
Research No. 14-03-31280-mol_a, and the Program
no. 24 of Presidium of Russian Academy of Sciences.
Elemental analysis, NMR, IR spectroscopy and DSC
measurements were carried out by the instrumentality
of equipment of Interlaboratory scientific center “Verkhne-
volzhskii region center of physicochemical researching.”
5. Chervonova, U.V., Gruzdev, M.S., Kolker, A.M.,
Manin, N.G., and Domracheva, N.E., Russ. J. Gen.
Chem., 2010, vol. 80, no. 10, p. 1954. DOI: 10.1134/
S1070363210100130.
7
16. Neises, B. and Steglich, W., Angew. Chem. Int. Ed.,
1978, vol. 17, no. 7, p. 522. DOI: 10.1002/anie.197805221.
17. Otera, J. and Nishikido, J., Esterification. Methods,
Reactions and Applications, Weinheim: Wiley-VCH,
2
010.
1
1
8. Hassner, A. and Alexanian, V., Tetrahedron Lett., 1978,
vol. 46, p. 4475. DOI: 10.1016/S0040-4039(01)95256-6.
REFERENCES
9. Hassner, A., Krepski, L., and Alexanian, V.,
Tetrahedron, 1978, vol. 34, no. 14, p. 2069. DOI:
10.1016/0040-4020(78)89005-X.
1
2
3
4
. Luminescence. From Theory to Applications, Ronda, C.,
Ed., Weinheim: Wiley-VCH, 2007.
. Campbell, N. and Barclay, B.M., Chem. Rev., 1947,
vol. 40, no. 3, p. 359. DOI: 10.1021/cr60127a001.
. Schmidt, A.W., Reddy, K.R., and Knolker, H.-J., Chem.
Rev., 2012, vol. 112, p. 3193. DOI: 10.1021/cr200447s.
. Ambrose, J.F., Caprenter, L.L., and Nelson, R.F.,
J. Electrochem. Soc., 1975, vol. 122, no. 7, p. 876. DOI:
0.1149/1.2134365.
20. Haslam, E., Tetrahedron, 1980, vol. 36, no. 17, p. 2409.
DOI: 10.1016/0040-4020(80)80219-5.
21. Lakowicz,
J.R.,
Principles
of
Fluorescence
Spectroscopy, New York: Springer, 2006.
22. Eksperimental’nye metody khimicheskoi kinetiki
(Experimental Methods of Chemical Kinetics),
Emmanuel, N.M. and Kuz’min, M.G., Eds., Moscow:
Mosk. Gos. Univ., 1985.
23. Rabek, J.F., Experimental Methods in Photochemistry
and Photophysics, New York: John Wiley & Sons,
1
5
6
7
. Ambrose, J.F. and Nelson, R.F., J. Electrochem. Soc.,
1
1
968, vol. 115, no. 11, p. 1159. DOI: 10.1149/
.2410929.
. Lamm, W., Pragst, F., and Jugelt, W., J. Prakt. Chem.,
975, vol. 317, no. 6, p. 995. DOI: 10.1002/
prac.19753170616.
. Maes, W., Vanderhaeghen, J., Smeets, S., Asokan, C.V.,
Van Renterghem, L.M., Duprez, F.E., Smet, M., and
1
982.
1
24. Moore, J.S. and Stupp, S.I., Macromolecules, 1990,
vol. 23, no. 1, p. 65. DOI: 10.1021/ma00203a013.
25. McAdam, C.J. and Simpson, J., Acta Crystallogr. E,
2008, vol. 64, p. o627. DOI: 10.1107/S1600536808004856.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 85 No. 6 2015