Photochromic and thermochromic spiranes. 34.*synthesis of photochromic 5-(4,5-diphenyl-1,3-oxazol-2-yl)-substituted spirobenzochromeneindolines

Article abstract of DOI:10.1007/s10593-011-0848-3

A simple and effective method is proposed for the synthesis of 4,5-diphenyloxazolyl-substituted o-hydroxynaphthaldehydes. Photochromic spirobenzochromeneindolines containing a 4,5-diphenyl-oxazole group at position 5 of the benzochromene fragment were obtained. In the cyclic form the new (diphenyloxazolyl)-substituted spiropyrans exhibit luminescent properties.

Full text of DOI:10.1007/s10593-011-0848-3

Chemistry of Heterocyclic Compounds, Vol. 47, No. 7, October 2011 (Russian original Vol. 47, No. 7, July, 2011)
PHOTOCHROMIC AND THERMOCHROMIC
SPIRANES. 34.* SYNTHESIS OF PHOTOCHROMIC
5-(4,5-DIPHENYL-1,3-OXAZOL-2-YL)-SUBSTITUTED
SPIROBENZOCHROMENEINDOLINES
N. A. Voloshin1, A. V. Chernyshev2**,
A. V. Metelitsa2, and V. I. Minkin2
A simple and effective method is proposed for the synthesis of 4,5-diphenyloxazolyl-substituted
o-hydroxynaphthaldehydes. Photochromic spirobenzochromeneindolines containing a 4,5-diphenyl-
oxazole group at position 5 of the benzochromene fragment were obtained. In the cyclic form the new
(diphenyloxazolyl)-substituted spiropyrans exhibit luminescent properties.
Keywords: merocyanines, spiropyrans, triaryloxazole, photochromism.
The synthesis and investigation of new effective photochromic systems with the aim of creating poly-
functional materials for molecular electronics and chemical sensors is a currently important problem [2, 3]. A
special place among known types of photochromic compounds is occupied by relatively easily synthesized
spiropyrans, the spectral and kinetic characteristics of which vary over a large range depending on the molecular
structure [2–4].
R3
Scheme 1
Me
O
Me
R2
Me
Me
)
h ( 
R2
R3
N
+
N
R1


–
R4

HO
R1
R4
1A
1B
_______
*For Communication 33, see [1].
**To whom correspondence should be addressed; e-mail: photo@ipoc.rsu.ru
1Southern Scientific Center, Russian Academy of Sciences, 41 Chehova St., Rostov-on-Don 344006, Russia.
2 Institute of Physical and Organic Chemistry, Southern Federal University, 194/2 Stachka Ave., Rostov-on-Don
344090, Russia.
__________________________________________________________________________________________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1055–1068, July, 2011. Original
article submitted August 11, 2010.
0009-3122/11/4707-0865©2011 Springer Science+Business Media, Inc.
865

The mechanism of the photochromic transformations of spiropyrans (Scheme 1) involves the thermally
and photochemically reversible heterolytic cleavage of the Cspiro–O bond of the cyclic isomer 1A followed by
cis–trans isomerization to the metastable merocyanine form 1B [2–4].
The insertion of various functional fragments into the spiropyran molecule opens up the possibility of
obtaining a wide range of polyfunctional photochromic molecular systems exhibiting magnetic [5], fluorescent
[6–9], and complexing [9–12] properties switched on by optical radiation. Earlier we reported on the synthesis
of photochromic 5-(4,5-diphenyl-1,3-oxazol-2-yl)-substituted spiropyrans, the acyclic isomer of which forms
reversibly complexes with the divalent cations of heavy metals [13]. The present work is a continuation of these
investigations and is devoted to the synthesis of new spiropyrans containing a diphenyloxazolyl group at
position 5 of the benzochromene fragment and their spectral and photochromic characteristics.
A convenient method for the production of 2,4,5-triaryl-1,3-oxazoles is cyclization of the esters of ben-
zoin and aromatic acids (desyl esters), which can be obtained by the acylation of benzoin by Davidson's method
[14]. In the case of 2-(hydroxyaryl)-4,5-diphenyl-1,3-oxazoles, the method of production of the desyl esters by
the alkylation of the salts of the corresponding carboxylic acids with desyl chloride under the conditions of
phase-transfer catalysis is preferred [15, 16].
5-(Diphenyloxazolyl)-substituted spiropyrans 1a–h were obtained in two stages by the reaction of
3H-indolium salts 2a–d with diphenyloxazolyl-substituted hydroxynaphthaldehydes 3a,b in acetic acid with
isolation of the obtained salts of o-hydroxynaphthylvinyl derivatives 4a–h and treatment of the latter with
ammonia (method A). The spiropyrans 1i–o were obtained in one stage by the condensation of the 3H-indolium
salts 2e–h with hydroxynaphthaldehydes 3a,b in the presence of triethylamine as base (method B) (Scheme 2).
The diphenyloxazolyl-substituted aldehydes 3a,b were obtained by the formylation of diphenyloxazolyl-
substituted naphthols 5a,b.
Instead of the previously described multistage method for the synthesis of the diphenyloxazolyl-
substituted aldehyde 3a [17] it is possible to propose a simple and effective method for the synthesis of the
aldehydes 3a,b (Scheme 3).
The starting compounds for the synthesis of the aldehydes 3a,b were the sodium salts of the acids 6a,b,
the alkylation of which with 2-chloro-1,2-diphenylethanone (desyl chloride, 7) under the conditions of phase-
transfer catalysis in a solid phase–liquid system in the presence of 15-crown-5 gave the desyl esters 8a,b.
Reaction of the desyl esters 8a,b with ammonium acetate in acetic acid by Davidson’s method [14] gave the
diphenyloxazolyl-substituted naphthols 5a,b, the formylation of which by the Duff method in acetic acid gave
the o-hydroxynaphthaldehydes 3a,b.
Scheme 2
R2
Method A
Me Me
4'
R1
1
2
10
9
R2
Me
Me
Me
6'
R1
Me
R1
N
R
O
7
3a,b
NH3
Ph
7'
+
Me
_
+
6
N
AcOH
NH
NH
HO
O
O
X
N
R
_
Ph
R
X
Ph
4a–h
1a–h
Ph
2a–d
Method B
3a,b
2e–h
1i–o
Et3N
866

Scheme 3
Ph
Ph
Cl
O
OH
OH
7
O
Ph
Ph
R2
R2
PTC
COONa
O
8a,b
6a,b
O
CHO
C6H12N4,
AcOH
NH4OAc,
AcOH
OH
OH
O
N
N
R2
R2
Ph
Ph
O
3a,b
5a,b
Ph
Ph
1a–c,e–g,k, 2a–c,e, 4a–c,e–g R = Me, 1d,h, 2d, 4d,h R = Pr, 1i,j,m,n, 2f,g R = All, 1l,o, 2h R = i-Bu, 1a,e, 2a, 4a,e R1 = Cl,
1b,f, 2b, 4b,f R1 = Me, 1c,g,j,n, 2c,g, 4c,g R1 = OMe, 1d,h,i,l,m,o, 2d,f,h, 4d,h R1 = H, 1k, 2e R1 = OAll,
1ad,i–l, 3a, 4a–d, 5,6,8a R2 = H, 1e–h,m–o, 3b, 4e–i, 5,6,8b R2 = OMe, 2a,g, 4a,e X = ClO4, 2b–f,h, 4b–d,f–i X = I
The colorless or weakly colored 5-diphenyloxazolyl-substituted spiropyrans 1a–o were purified by
chromatography and recrystallized. The structure of compounds 1a–o, 3a,b, 5a,b, and 8a,b was established by
1H NMR spectroscopy and confirmed by elemental analysis.
1
By H NMR spectroscopy it is possible to establish quickly and accurately the structure of spiropyrans
of the indoline series from the characteristic shifts, spin–spin coupling constants, and the number of different
types of protons. The signals of such characteristic (indicator) groups as a gem-dimethyl group, an N-alkyl
substituent, and the protons of the C(3)=C(4) double bond are usually determined easily and have different
chemical shifts for the open and closed forms [18-20].
The upfield region of the spectrum of the spiropyrans contains two easily identified signals from the
magnetically nonequivalent geminal methyl groups, the signal of the N-alkyl substituent (Me, Pr, All, i-Bu), and
signals of the corresponding indicator groups of the substituents (Me, OMe, OAll) in the spiropyran.
The prochirality of the methylene group of the N-allyl substituent (spiropyrans 1i,j,m,n) and the methyl
groups and the protons of the methylene group of the N-isobutyl substituent (spiropyrans 1l,o) leads to
diastereotopic splitting of the signals of these groups, which appear in the form of two double doublets at 3.00
and 3.06 and two doublets at 0.87 and 0.91 ppm respectively.
The downfield part of the spectrum of the spiropyrans 1a–o contains several groups of interdependent
signals of protons belonging to the indoline and pyran fragments of the molecule and the signals of two groups,
each of five interacting nuclei, belonging to the phenyls of the diphenyloxazolyl substituent. Unlike the
diphenyloxazolyl-substituted naphthols 5 and aldehydes 3, in the 1H NMR spectra of which the signals of the ten
protons of the phenyl groups appear in the form of four-proton and six-proton multiplets, in the 1H NMR spectra
of the spiropyrans 1 the signals of the protons of the two phenyl rings in the oxazole group form a complex
picture of four multiplets with integral intensities of 2:3:3:2.
1
Thus, the structure of the obtained spiropyrans is confirmed unambiguously by the data from H NMR
spectroscopy (two signals from the magnetically nonequivalent geminal methyl groups, signals from the protons
of the phenyl rings of the diphenyloxazolyl group, diastereotopic splitting of the signals for the protons of the
N-alkyl substituent, the values of the chemical shifts of the protons and the spin–spin coupling constants of the
diastereotopic protons of the N-isobutyl and N-allyl substituents, the protons of the double bond in the pyran
867

fragment, and the protons of the indoline and pyran fragments). The absence of signals for the N-methyl and
gem-dimethyl groups, the trans-vinyl protons, and other protons of the indoline and benzochromene fragments
in the regions of the spectra characteristic of the open merocyanine form indicates that the obtained compounds
exist in solution in CDCl3 mainly in the spirocyclic form.
The electronic absorption spectra of the cyclic forms 1A of the spiropyrans 1a–o in toluene solution are
characterized by the presence of several bands. The less intense long-wave band with a molar extinction
coefficient at the maximum of 4.5–9.0×103 l·mol−1·cm−1 is characterized by two poorly resolved maxima in the
region of 380–395 nm (compounds 1a–c,i–l, Table 1). The introduction of a methoxyl substituent at position 8
of the benzochromene fragment of the molecule gives rise to a bathochromic shift of this band by 10–15 nm
(compounds 1e–h,m–o). The position of the maxima of the more intense short-wave absorption bands of
compounds 1a–o (ε = 36.4–20.4×103 l·mol−1·cm−1) does not depend on the nature of the substituents and is
located in the region of 310 and 340 nm.
Fig. 1. The absorption spectrum (1) of a solution of 1g and the fluorescence emission (2)
and excitation (3) spectra of the spirocyclic isomer 1g, T = 293 K, solvent toluene. The
phosphorescence emission (4) and excitation (5) spectra of the spirocyclic isomer 1g,
T = 77 K, solvent toluene–ethanol–diethyl ether.
It was established that the cyclic forms of the spiropyrans at 293 K have fluorescent characteristics. The
fluorescence emission spectrum represents a broad band in the region of 400–600 nm with poorly resolved
maxima at 410 and 430 nm. As also in the case of the absorption spectra, the introduction of a methoxyl
substituent at position 8 of the benzochromene part of the molecule leads to a bathochromic shift of the maxima
of the fluorescence band by 20–25 nm.
At 77 K the solutions of compounds 1a–o exhibit strong fluorescence, which is characterized by a struc-
tured band with maxima at 580, 630, and 690 nm; their position hardly depends at all on the nature of the
substituents in the indoline and pyran parts of the molecule. The fluorescence and phosphorescence excitation
spectra practically coincide with each other, and the position of their maxima correlates well with the position of
the maxima in the absorption spectrum, providing grounds for attributing the observed luminescent characteris-
tics to the spirocyclic isomers of the synthesized compounds (Fig. 1, Table 1).
868

869






870

Fig. 2. The variation of the absorption spectra of a solution of 1g in acetone during
irradiation with light at 365 nm, spectrum recording interval 5 s.
Compounds 1a–o exhibit photochromic properties at temperatures below room temperature, and this is
due to the high rates of thermal recyclization of the isomers 1B → 1A. Thus, during the exposure of acetone
solutions of these compounds in the region of the long-wave absorption of the cyclic forms 1A at T 270 K their
colorization, accompanied by the appearance of bands in the electronic absorption spectra in the region of
550-650 nm (Fig. 2, Table 1) characteristic of the noncyclic merocyanine isomers 1B of the spiropyrans, is
observed [2–4]. The position of the maximum of the long-wave absorption band of the merocyanine form 1B in
the series of compounds 1a–o is shifted appreciably into the long-wave region of the spectrum with the
introduction of the methoxy group at position 5 of the benzochromene part of the spiropyran.
Thus, the obtained new 5-(4,5-diphenyl-1,3-oxazol-2-yl)-substituted spirobenzochromeneindolines pos-
sess fluorescence and phosphorescence in the spirocyclic form and exhibit photochromic properties in solutions.
EXPERIMENTAL
The 1H NMR spectra were recorded on a Varian Unity-300 spectrometer (300 MHz) in CDCl3. The sig-
nals were assigned with reference to the signal of the residual protons of the deuterated solvent (δ 7.26 ppm).
The electronic absorption spectra of the investigated compounds were recorded on an Agilent 8453 spectropho-
tometer with a thermostat attachment for the samples, and the electronic spectra were recorded on a Varian Cary
Eclipse spectrofluorimeter. Photolysis of the solutions was realized with a DRSh-250 lamp with a set of
interference filters. Toluene and acetone (Aldrich) of spectral purity were used to prepare the solutions. The
sodium salt of the acid 6b was the commercial product (Fluka).
The sodium salt of the acid 6a, the desyl chloride 7, and the 3H-indolium salts 2a-d were obtained by
the previously described methods [16, 21–25].
2-Oxo-1,2-diphenyl Esters of 3-Hydroxy-2-naphthoic Acids 8a,b (General Method). A mixture of
the sodium salt 6a,b (33 mol), 15-crown-5 (1 ml, 5 mmol), and acetonitrile (90 ml) was stirred at 70°C for
30 min, and desyl chloride 7 (6.93 g, 30 mmol) was added. The mixture was stirred with boiling for 7 h and
poured into 200 ml of water and ice. The precipitate was filtered off, washed with water, and dried. The obtained
esters were recrystallized from a mixture of 2-propanol and toluene.
871

2-Oxo-1,2-diphenylethyl Ester of 3-Hydroxy-2-naphthoic Acid (8a). Yield 81%; mp 152–153.5°C
1
(2-propanol–toluene, 3:1). H NMR spectrum, δ, ppm (J, Hz): 7.17 (1Н, s, 2-СOOCH); 7.29–7.34 (2H, m,
H-4,7); 7.42–7.64 (9Н, m, Н-6, H Ph); 7.68 (1Н, d, J = 8.4, Н-5); 7.82 (1Н, d, J = 8.4, Н-8); 8.00–8.03 (2Н, m,
H Ph); 8.64 (1H, s, H-1); 10.10 (1H, s, 3-OH). Found, %: C 78.67; H 4.65. C25H18O4. Calculated, %: C 78.52;
H 4.74.
2-Oxo-1,2-diphenylethyl Ester of 3-Hydroxy-7-methoxy-2-naphthoic Acid (8b). Yield 74%; mp
1
159–160°C (2-propanol–toluene, 2:1). H NMR spectrum, δ, ppm (J, Hz): 3.86 (3H, s, 7-OCH3); 7.08 (1Н, d,
J = 2.4, Н-8); 7.15 (1Н, s, 2-СOOCH); 7.17 (1Н, dd, J = 8.8, J = 2.4, Н-6); 7.25 (1Н, s, Н-4); 7.40–7.46 (5Н, m,
H Ph); 7.52–7.62 (4Н, m, Н-5, H Ph); 7.98–8.01 (2Н, m, H Ph); 8.51 (1Н, s, Н-1); 9.92 (1Н, s, 3-ОН). Found,
%: C 75.90; H 4.95. C26H20O5. Calculated, %: C 75.72; H 4.89.
3-(4,5-Diphenyl-1,3-oxazol-2-yl)-2-naphthols 5a,b (General Method). A mixture of desyl naphthoate
8a,b (20 mmol), ammonium acetate (9.24 g, 120 mmol), and acetic acid (40 ml) was boiled for 4 h. The mixture
was poured into ice (500 g), and the precipitate was filtered off, washed with water, and dried. The obtained
naphthols 5a,b were recrystallized from a mixture of 2-propanol and toluene.
3-(4,5-Diphenyl-1,3-oxazol-2-yl)-2-naphthol (5a). Yield 69%; mp 154–155°C (2-propanol–toluene,
3:1). 1H NMR spectrum, δ, ppm (J, Hz): 7.35 (1Н, m, Н-7); 7.40–7.45 (7Н, m, Н-1, H Ph); 7.48 (1Н, m, Н-6);
7.71–7.77 (5Н, m, Н-5, H Ph); 7.86 (1Н, d, J = 8.4, Н-8); 8.49 (1Н, s, Н-4); 11.15 (1Н, s, 2-ОН). Found, %:
C 82.75; H 4.79; N 3.76. C25H17NO2. Calculated, %: C 82.63; H 4.71; N 3.85.
3-(4,5-Diphenyl-1,3-oxazol-2-yl)-6-methoxy-2-naphthol (5b). Yield 72%; mp 194–195.5°C (2-propanol–
toluene, 1:1). 1H NMR spectrum, δ, ppm (J, Hz): 3.90 (3Н, s, 6-ОСН3); 7.14 (1Н, d, J = 2.6, Н-5); 7.15 (1Н, dd,
J = 9.7, J = 2.6, Н-7); 7.37 (1Н, s, Н-1); 7.39–7.46 (6Н, m, H Ph); 7.61 (1Н, d, J = 9.7, Н-8); 7.70-7.75 (4Н, m,
H Ph); 8.37 (1Н, s, Н-4); 10.95 (1Н, s, 2-ОН). Found, %: C 79.48; H 4.95; N 3.50. C26H19NO3. Calculated, %:
C 79.37; H 4.87; N 3.56.
2-Hydroxy-3-(4,5-diphenyl-1,3-oxazol-2-yl)-1-naphthaldehydes 3a,b (General Method). A mixture
of the naphthol 5a,b (10 mmol), hexamethylenetetramine (2.80 g, 20 mmol), and acetic acid (40 ml) was stirred
at 95–100°C for 5 h 30 min. A mixture of conc. HCl (15 ml) and water (18 ml) was added, and the reaction
mixture was stirred at 95–100°C for 1 h. It was poured into 175 ml of water, and the precipitate was filtered off,
washed with water, and dried. The obtained aldehydes 3a,b were purified by column chromatography on Al2O3
(eluent chloroform) and recrystallized from a 2:1 mixture of benzene and acetonitrile.
2-Hydroxy-3-(4,5-diphenyl-1,3-oxazol-2-yl)-1-naphthaldehyde (3a). Yield 51%; mp 213–214°C. The
1H NMR spectrum of the obtained compound was identical with the spectrum of the compound obtained earlier
[17]. Found, %: C 79.67; H 4.24; N 3.70. C26H17NO3. Calculated, %: C 79.78; H 4.38; N 3.58.
2-Hydroxy-3-(4,5-diphenyl-1,3-oxazol-2-yl)-6-methoxy-1-naphthaldehyde (3b). Yield 38%; mp
217.5–218.5°C. 1H NMR spectrum, δ, ppm (J, Hz): 3.93 (3Н, s, 6-ОСН3); 7.18 (1Н, d, J = 2.7, Н-5); 7.34 (1Н,
dd, J = 9.5, J = 2.7, Н-7); 7.41–7.49 (6Н, m, H Ph); 7.71–7.76 (4Н, m, H Ph); 8.58 (1Н, s, Н-4); 9.19 (1Н, d,
J = 9.5, Н-8); 11.02 (1Н, s, 1-СНО); 12.22 (1Н, s, 2-ОН). Found, %: C 76.80; H 4.65; N 3.43. C27H19NO4.
Calculated, %: C 76.95; H 4.54; N 3.32.
3',3'-Dimethyl-5-(4,5-diphenyl-1,3-oxazol-2-yl)spiro[benzo[f]chromene-3,2'-indolines] 1a–h (General
Method). A. A mixture of the 3H-indolium salt 2a–d (1 mmol), aldehyde 3a,b (1 mmol), and glacial acetic acid
(8 ml) was boiled for 5 h 30 min and kept at ~20°C for 12 h. The precipitate was filtered off, washed with ether,
dried, and then used without further purification. Dry ammonia was passed into a suspension of the obtained salt
4a–h in benzene (20 ml), the solvent was evaporated, and the residue was purified by column chromatography
on Al2O3 (eluent benzene). The spiropyrans 1a–h were recrystallized from a 2:1 mixture of heptane and toluene.
3',3'-Dimethyl-5-(4,5-diphenyl-1,3-oxazol-2-yl)spiro[benzo[f]chromene-3,2'-indolines] 1i–o (General
Method). B. A mixture of the 3H-indolium salt 2e–h (1 mmol), triethylamine (0.14 ml, 1 mmol), and aldehyde
3a,b (1 mmol) in benzene (8 ml) and 2-propanol (2 ml) was boiled for 10 h and evaporated. The residue was
purified by column chromatography on Al2O3 (eluent benzene). The spiropyrans 1i–o were recrystallized from a
3:1 mixture of isooctane and toluene.
872

5'-Chloro-5-(4,5-diphenyl-1,3-oxazol-2-yl)-1',3',3'-trimethylspiro[benzo[f]chromene-3,2'-indoline]
1
(1a). Yield 50%; mp 219.5–221°C. H NMR spectrum, δ, ppm (J, Hz): 1.26 (3H, s, 3'-CH3); 1.43 (3H, s,
3'-CH3); 2.77 (3H, s, 1'-CH3); 5.88 (1H, d, J = 10.5, H-2); 6.45 (1H, d, J = 8.2, H-7'); 7.08 (1H, d, J = 2.1, H-4');
7.13 (1H, dd, J = 8.2, J = 2.1, H-6'); 7.15–7.19 (2Н, m, H Ph); 7.30–7.42 (7Н, m, H-8, H Ph); 7.57 (1H, dd,
J = 8.5, J = 6.9, J = 1.4, H-9); 7.59–7.62 (2Н, m, H Ph); 7.68 (1H, d, J = 10.5, H-1); 7.87 (1H, d, J = 8.1, H-7);
8.05 (1H, d, J = 8.5, H-10); 8.62 (1H, s, H-6). Found, %: C 78.68; H 5.15; N 4.89. C38H29ClN2O2. Calculated,
%: C 78.54; H 5.03; N 4.82.
5-(4,5-Diphenyl-1,3-oxazol-2-yl)-1',3',3',5'-tetramethylspiro[benzo[f]chromene-3,2'-indoline] (1b).
Yield 43%; mp 222–223°C. 1H NMR spectrum, δ, ppm (J, Hz): 1.25 (3H, s, 3'-CH3); 1.41 (3H, s, 3'-CH3); 2.34
(3H, s, 5'-CH3); 2.78 (3H, s, 1'-CH3); 5.90 (1H, d, J = 10.5, H-2); 6.47 (1H, d, J = 7.8, H-7'); 6.93 (1H, m, H-4');
7.00 (1H, m, H-6'); 7.13–7.16 (2Н, m, H Ph); 7.21–7.29 (3Н, m, H Ph); 7.31–7.41 (4Н, m, H-8, H Ph); 7.56
(1H, ddd, J = 8.4, J = 6.9, J = 1.4, H-9); 7.61–7.64 (2Н, m, H Ph); 7.65 (1H, d, J = 10.5, H-1); 7.86 (1H, d,
J = 8.1, H-7); 8.05 (1H, d, J = 8.5, H-10); 8.60 (1H, s, Н-6). Found, %: C 83.37; H 5.83; N 5.09. C39H32N2O2.
Calculated, %: C 83.54; H 5.75; N 5.00.
5-(4,5-Diphenyl-1,3-oxazol-2-yl)-1',3',3'-trimethyl-5'-methoxyspiro[benzo[f]chromene-3,2'-indoline]
1
(1c). Yield 42%; mp 192.5–193.5°C. H NMR spectrum, δ, ppm (J, Hz): 1.27 (3H, s, 3'-CH3); 1.43 (3H, s,
3'-CH3); 2.74 (3H, s, 1'-CH3); 3.79 (3H, s, 5-OCH3); 5.90 (1H, d, J = 10.5, H-2); 6.46 (1H, d, J = 8.3, H-7'); 6.71
(1H, dd, J = 8.3, J = 2.4, H-6'); 6.78 (1H, d, J = 2.4, H-4'); 7.12–7.16 (2Н, m, H Ph); 7.26–7.40 (7Н, m, H-8,
H Ph); 7.56 (1H, ddd, J = 8.4, J = 6.9, J = 1.4, H-9); 7.61–7.64 (2Н, m, H Ph); 7.66 (1H, d, J = 10.5, H-1); 7.86
(1H, d, J = 8.1, H-7); 8.05 (1H, d, J = 8.5, H-10); 8.62 (1H, s, Н-6). Found, %: C 81.37; H 5.46; N 4.75.
C39H32N2O3. Calculated, %: C 81.23; H 5.59; N 4.86.
5-(4,5-Diphenyl-1,3-oxazol-2-yl)-3',3'-dimethyl-1'-propylspiro[benzo[f]chromene-3,2'-indoline] (1d).
1
Yield 45%; mp 159.5–161°C. H NMR spectrum, δ, ppm (J, Hz): 0.84 (3Н, t, J = 7.4, 1'-CH2CH2CH3); 1.25
(3H, s, 3'-CH3); 1.42 (3H, s, 3'-CH3); 1.65 (2Н, m, 1'-CH2CH2CH3); 3.25 (2Н, m, 1-CH2CH2CH3); 5.89 (1H, d,
J = 10.5, H-2); 6.58 (1H, d, J = 7.7, H-7'); 6.87 (1H, td, J = 7.4, J = 0.9, H-5'); 7.09–7.13 (3Н, m, H-4', H Ph);
7.21 (1H, dt, J = 7.6, J = 1.2, H-6'); 7.23–7.27 (3Н, m, H Ph); 7.31–7.40 (4H, m, H-8, H Ph); 7.56 (1H, ddd,
J = 8.3, J = 6.9, J = 1.3, H-9); 7.60–7.64 (3Н, m, H-1, H Ph); 7.86 (1H, d, J = 8.1, H-7); 8.05 (1H, d, J = 8.5,
H-10); 8.61 (1H, s, Н-6). Found, %: C 83.45; H 6.03; N 4.98. C40H34N2O2. Calculated, %: C 83.60; H 5.96;
N 4.87.
5'-Chloro-5-(4,5-diphenyl-1,3-oxazol-2-yl)-8-methoxy-1',3',3'-trimethylspiro[benzo[f]chromene-
1
3,2'-indoline] (1e). Yield 46%; mp 225–226°C. H NMR spectrum, δ, ppm (J, Hz): 1.26 (3H, s, 3'-CH3); 1.42
(3H, s, 3'-CH3); 2.76 (3H, s, 1'-CH3); 3.92 (3H, s, 8-OCH3); 5.87 (1H, d, J = 10.5, H-2); 6.44 (1H, d, J = 8.2,
H-7'); 7.08 (1H, d, J = 2.1, H-4'); 7.14 (1H, dd, J = 8.1, J = 2.1, H-6'); 7.15–7.18 (3Н, m, H-7, H Ph); 7.25 (1H,
dd, J = 9.2, J = 2.7, H-9); 7.29–7.41 (6H, m, H Ph); 7.60–7.64 (3Н, m, H-1, H Ph); 7.96 (1H, d, J = 9.2, H-10);
8.53 (1H, s, Н-6). Found, %: C 76.54; H 5.25; N 4.66. C39H31ClN2O3. Calculated, %: C 76.65; H 5.11; N 4.58.
5-(4,5-Diphenyl-1,3-oxazol-2-yl)-8-methoxy-1',3',3',5'-tetramethylspiro[benzo[f]chromene-3,2'-indo-
1
line] (1f). Yield 46%; mp 241–242°C. H NMR spectrum, δ, ppm (J, Hz): 1.25 (3H, s, 3'-CH3); 1.41 (3H, s,
3'-CH3); 2.34 (3H, s, 5'-CH3); 2.77 (3H, s, 1'-CH3); 3.91 (3H, s, 8-OCH3); 5.89 (1H, d, J = 10.5, H-2); 6.46 (1H,
d, J = 7.8, H-7'); 6.93 (1H, d, J = 1.6, H-4'); 7.00 (1H, m, H-6'); 7.13–7.18 (3Н, m, H-7, H Ph); 7.20–7.28 (4Н,
m, Н-9, H Ph); 7.30–7.39 (3Н, m, H Ph); 7.61–7.64 (2Н, m, H Ph); 7.59 (1H, d, J = 10.5, H-1); 7.96 (1H, d,
J = 9.3, H-10); 8.51 (1H, s, H-6). Found, %: C 81.17; H 5.69; N 4.85. C40H34N2O3. Calculated, %: C 81.33;
H 5.80; N 4.74.
5-(4,5-Diphenyl-1,3-oxazol-2-yl)-5',8-dimethoxy-1',3',3'-trimethylspiro[benzo[f]chromene-3,2'-indo-
1
line] (1g). Yield 47%; mp 231–232°C. H NMR spectrum, δ, ppm (J, Hz): 1.27 (3H, s, 3'-CH3); 1.42 (3H, s,
3'-CH3); 2.73 (3H, s, 1'-CH3); 3.79 (3H, s, 5'-OCH3); 3.92 (3H, s, 8-OCH3); 5.90 (1H, d, J = 10.5, H-2); 6.45
(1H, d, J = 8.3, H-7'); 6.72 (1H, dd, J = 8.3, J = 2.6, H-6'); 6.78 (1H, d, J = 2.6, H-4'); 7.12–7.18 (3Н, m, H-7,
873

H Ph); 7.21–7.29 (4Н, m, H-9, H Ph); 7.31–7.40 (3Н, m, H Ph); 7.58–7.65 (3Н, m, H-1, H Ph); 7.96 (1H, d,
J = 9.2, H-10); 8.53 (1H, s, H-6). Found, %: C 79.05; H 5.74; N 4.73. C40H34N2O4. Calculated, %: C 79.19;
H 5.65; N 4.62.
5-(4,5-Diphenyl-1,3-oxazol-2-yl)-8-methoxy-3',3'-dimethyl-1'-propylspiro[benzo[f]chromene-3,2'-indo-
line] (1h). Yield 45%; mp 229–230°C. 1H NMR spectrum, δ, ppm (J, Hz): 0.84 (3Н, t, J = 7.4, 1'-CH2CH2CH3);
1.24 (3H, s, 3'-CH3); 1.41 (3H, s, 3'-CH3); 1.64 (2Н, m, 1'-CH2CH2CH3); 3.24 (2Н, m, 1'-CH2CH2CH3); 3.92
(3H, s, 8-OCH3); 5.89 (1H, d, J = 10.5, H-2); 6.58 (1H, d, J = 7.7, H-7'); 6.87 (1H, td, J = 7.4, J = 0.9, H-5');
7.08–7.18 (4Н, m, H-4',7, H Ph); 7.19–7.27 (5Н, m, H-6',9, H Ph); 7.31–7.39 (3H, m, H Ph); 7.57 (1H, d,
J = 10.5, H-1); 7.61–7.64 (2Н, m, H Ph); 7.95 (1H, d, J = 9.2, H-10); 8.52 (1H, s, Н-6). Found, %: C 81.25;
H 5.91; N 4.76. C41H36N2O3. Calculated, %: C 81.43; H 6.00; N 4.63.
1'-Allyl-5-(4,5-diphenyl-1,3-oxazol-2-yl)-3',3'-dimethylspiro[benzo[f]chromene-3,2'-indoline] (1i).
Yield 44%; mp 179–180°C. 1H NMR spectrum, δ, ppm (J, Hz): 1.29 (3H, s, 3'-CH3); 1.44 (3H, s, 3'-CH3); 3.80
(1Н, ddt, J = 17.3, J = 5.3, J = 1.6, 1'-CH2CH=CH2); 4.04 (1Н, ddt, J = 17.3, J = 4.2, J = 2.0, 1'-CH2CH=CH2);
4.99 (1Н, dq, J = 10.3, J = 1.7, 1'-CH2CH=CH2); 5.15 (1Н, dq, J = 17.2, J = 1.8, 1'-CH2CH=CH2); 5.89 (1Н, m,
1'-CH2CH=CH2); 5.90 (1H, d, J = 10.5, H-2); 6.59 (1H, d, J = 7.7, H-7'); 6.90 (1H, td, J = 7.4, J = 0.9, H-5');
7.09–7.16 (3Н, m, H-4', H Ph); 7.20 (1H, td, J = 7.6, J = 1.3, H-6'); 7.23–7.26 (3Н, m, H Ph); 7.31–7.41 (4H, m,
H-8, H Ph); 7.56 (1H, ddd, J = 8.4, J = 6.9, J = 1.4, H-9); 7.60–7.65 (3Н, m, H-1, H Ph); 7.86 (1H, d, J = 8.1,
H-7); 8.04 (1H, d, J = 8.5, H-10); 8.61 (1H, s, H-6). Found, %: C 83.74; H 5.69; N 4.80. C40H32N2O2.
Calculated, %: C 83.89; H 5.63; N 4.89.
1'-Allyl-5-(4,5-diphenyl-1,3-oxazol-2-yl)-5'-methoxy-3',3'-dimethylspiro[benzo[f]chromene-3,2'-indo-
1
line] (1j). Yield 60%; mp 195–196.5°C. H NMR spectrum, δ, ppm (J, Hz): 1.29 (3H, s, 3'-CH3); 1.43 (3H, s,
3'-CH3); 3.72 (1H, ddt, J = 17.2, J = 5.4, J = 1.6, 1'-CH2CH=CH2); 3.78 (3H, s, 5'-OCH3); 3.98 (1H, ddt,
J = 17.2, J = 4.5, J = 2.1, 1'-CH2CH=CH2); 4.98 (1H, dq, J = 10.3, J = 1.7, 1'-CH2CH=CH2); 5.14 (1H, dq,
J = 17.2, J = 1.7, 1'-CH2CH=CH2); 5.88 (1H, m, 1'-CH2CH=CH2); 5.90 (1H, d, J = 10.5, H-2); 6.48 (1H, d,
J = 8.4, H-7'); 6.69 (1H, dd, J = 8.4, J = 2.6, H-6'); 6.78 (1H, d, J = 2.6, H-4'); 7.12–7.17 (2H, m, H Ph);
7.24-7.28 (3H, m, H Ph); 7.32–7.40 (4H, m, H-8, H Ph); 7.55 (1H, ddd, J = 8.4, J = 6.9, J = 1.4, H-9); 7.60–7.65
(3H, m, H-1, H Ph); 7.86 (1H, dd, J = 8.2, J = 1.3, H-7); 8.03 (1H, d, J = 8.5, H-10); 8.61 (1H, s, H-6). Found,
%: C 81.54; H 5.60; N 4.56. C41H34N2O3. Calculated, %: C 81.70; H 5.69; N 4.65.
5'-Allyloxy-5-(4,5-diphenyl-1,3-oxazol-2-yl)-1',3',3'-trimethylspiro[benzo[f]chromene-3,2'-indo-
1
line] (1k). Yield 50%; mp 188–189.5°C. H NMR spectrum, δ, ppm (J, Hz): 1.27 (3H, s, 3'-CH3); 1.42 (3H, s,
3'-CH3); 2.74 (3H, s, 1'-CH3); 4.46 (2H, ddd, J = 5.4, J = 2.6, J = 1.3, 5'-OCH2CH=CH2); 5.28 (1H, dq, J = 10.4,
J = 1.4, 5'-OCH2CH=CH2); 5.44 (1H, dq, J = 17.2, J = 1.6, 5'-OCH2CH=CH2); 5.90 (1H, d, J = 10.5, H-2); 6.10
(1H, ddt, J = 17.2, J = 10.6, J = 5.3, 5'-OCH2CH=CH2); 6.44 (1H, d, J = 8.3, H-7'); 6.73 (1H, dd, J = 8.3,
J = 2.5, H-6'); 6.80 (1H, d, J = 2.5, H-4'); 7.14–7.18 (2H, m, H Ph); 7.26–7.40 (7H, m, H-8, H Ph); 7.56 (1H,
ddd, J = 1.4, J = 6.8, J = 8.4, H-9); 7.61–7.64 (2H, m, H Ph); 7.66 (1Н, d, J = 10.5, H-1); 7.86 (1H, d, J = 8.1,
H-7); 8.05 (1H, d, J = 8.5, H-10); 8.62 (1H, s, H-6). Found, %: C 81.59; H 5.81; N 4.59. C41H34N2O3.
Calculated, %: C 81.70; H 5.69; N 4.65.
5-(4,5-Diphenyl-1,3-oxazol-2-yl)-1'-isobutyl-3,3-dimethylspiro[benzo[f]chromene-3,2'-indoline] (1l).
1
Yield 38%; mp 180–181°C. H NMR spectrum, δ, ppm (J, Hz): 0.87 (3Н, d, J = 6.7, 1'-CH2CH(CH3)2); 0.91
(3Н, d, J = 6.6, 1'-CH2CH(CH3)2); 1.27 (3H, s, 3'-CH3); 1.42 (3H, s, 3'-CH3); 2.06 (1Н, m, 1'-CH2CH(CH3)2);
3.00 (1Н, dd, J = 14.4, J = 8.8, 1'-CH2CH(CH3)2); 3.06 (1Н, dd, J = 14.4, J = 6.3, 1'-CH2CH(CH3)2); 5.92 (1H,
d, J = 10.6, H-2); 6.57 (1H, d, J = 7.8, H-7'); 6.87 (1H, td, J = 7.4, J = 0.9, H-5'); 7.09–7.14 (3Н, m, H-4', H Ph);
7.18 (1H, td, J = 7.6, J = 1.3, H-6'); 7.24–7.29 (3Н, m, H Ph); 7.31–7.40 (4H, m, H-8, H Ph); 7.56 (1H, ddd,
J = 8.4, J = 6.9, J = 1.4, H-9); 7.59–7.63 (3Н, m, H-1, H Ph); 7.85 (1H, d, J = 8.1, H-7); 8.04 (1H, d, J = 8.5,
H-10); 8.58 (1H, s, H-6). Found, %: C 83.77; H 6.09; N 4.64. C41H36N2O2. Calculated, %: C 83.64; H 6.16;
N 4.76.
874

1'-Allyl-5-(4,5-diphenyl-1,3-oxazol-2-yl)-3',3'-dimethyl-8-methoxyspiro[benzo[f]chromene-3,2'-indo-
line] (1m). Yield 40%; mp 212.5–214°C. 1H NMR spectrum, δ, ppm (J, Hz): 1.28 (3H, s, 3'-CH3); 1.43 (3H, s,
3'-CH3); 3.79 (1Н, ddt, J = 17.3, J = 5.2, J = 1.7, 1'-CH2CH=CH2); 3.92 (3H, s, 8-OCH3); 4.04 (1Н, ddt,
J = 17.3, J = 4.2, J = 2.0, 1'-CH2CH=CH2); 4.98 (1Н, dq, J = 10.3, J = 1.7, 1'-CH2CH=CH2); 5.14 (1Н, dq,
J = 17.2, J = 1.8, 1'-CH2CH=CH2); 5.89 (1Н, m, 1'-CH2CH=CH2); 5.90 (1H, d, J = 10.5, H-2); 6.58 (1H, d,
J = 7.7, H-7'); 6.89 (1H, td, J = 7.4, J = 0.9, H-5'); 7.09–7.18 (4Н, m, H-4',7, H Ph); 7.19–7.26 (5Н, m, H-6',9,
H Ph); 7.31–7.39 (3H, m, H Ph); 7.57 (1H, d, J = 10.5, H-1); 7.60–7.64 (2Н, m, H Ph); 7.94 (1H, d, J = 9.3,
H-10); 8.52 (1H, s, Н-6). Found, %: C 81.56; H 5.77; N 4.76. C41H34N2O3. Calculated, %: C 81.70; H 5.69;
N 4.65.
1'-Allyl-5-(4,5-diphenyl-1,3-oxazol-2-yl)-5',8-dimethoxy-3',3'-dimethylspiro[benzo[f]chromene-
3,2'-indoline] (1n). Yield 41%; mp 221–222.5°C. 1H NMR spectrum, δ, ppm (J, Hz): 1.28 (3H, s, 3'-CH3); 1.42
(3H, s, 3'-CH3); 3.71 (1H, ddt, J = 17.2, J = 5.4, J = 1.6, 1'-CH2CH=CH2); 3.78 (3H, s, 5'-OCH3); 3.92 (3H, s,
8-OCH3); 3.97 (1H, ddt, J = 17.2, J = 4.4, J = 2.1, 1'-CH2CH=CH2); 4.98 (1H, dq, J = 10.2, J = 1.7,
1'-CH2CH=CH2); 5.14 (1H, dq, J = 17.2, J = 1.7, 1'-CH2CH=CH2); 5.88 (1H, m, 1'-CH2CH=CH2); 5.89 (1H, d,
J = 10.5, H-2); 6.48 (1H, d, J = 8.4, H-7'); 6.69 (1H, dd, J = 2.6, J = 8.4, H-6'); 6.78 (1H, d, J = 2.5, H-4');
7.12-7.18 (3Н, m, H-7, H Ph); 7.21–7.40 (7Н, m, H-9, H Ph); 7.57 (1H, d, J = 10.5, H-1); 7.62–7.65 (2Н, m,
H Ph); 7.94 (1H, d, J = 9.3, H-10); 8.52 (1H, s, H-6). Found, %: C 79.65; H 5.90; N 4.47. C42H36N2O4.
Calculated, %: C 79.72; H 5.73; N 4.43.
5-(4,5-Diphenyl-1,3-oxazol-2-yl)-1'-isobutyl-8-methoxy-3',3'-dimethylspiro[benzo[f]chromene-
1
3,2'-indoline] (1o). Yield 39%; mp 204–205°C. H NMR spectrum, δ, ppm (J, Hz): 0.88 (3Н, d, J = 6.7,
1'-CH2CH(CH3)2); 0.91 (3Н, d, J = 6.6, 1'-CH2CH(CH3)2); 1.27 (3H, s, 3'-CH3); 1.42 (3H, s, 3'-CH3); 2.06 (1Н,
m, 1'-CH2CH(CH3)2); 3.00 (1Н, dd, J = 14.5, J = 8.8, 1'-CH2CH(CH3)2); 3.06 (1Н, dd, J = 14.5, J = 6.4,
1'-CH2CH(CH3)2); 3.92 (3H, s, 8-OCH3); 5.92 (1H, d, J = 10.5, H-2); 6.58 (1H, d, J = 7.8, H-7'); 6.87 (1H, dt,
J = 7.4, J = 0.9, H-5'); 7.10–7.18 (4Н, m, H-4',7, H Ph); 7.19–7.28 (5Н, m, H-6',9, H Ph); 7.31–7.39 (3H, m,
H Ph); 7.56 (1H, d, J = 10.5, H-1); 7.60–7.63 (2Н, m, H Ph); 7.95 (1H, d, J = 9.2, H-10); 8.50 (1H, s, H-6).
Found, %: C 81.68; H 6.11; N 4.41. C42H38N2O3. Calculated, %: C 81.53; H 6.19; N 4.53.
The work was carried out with financial support from the Ministry of Education and Science of the Rus-
sian Federation (Federal Target Program “Scientific and Scientific-Pedagogical Staff of Innovative Russia,
2009-2013, State contract No. P2435).
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