Vilsmeier-Haack reagent: An efficient reagent for the transformation of substituted 1,3-naphthoxazines into xanthene-type dyes

Article abstract of DOI:10.1016/j.tet.2019.04.007

Derivatives of 1,3-naphthoxazines containing from five to seven-membered spiro ring – under Vilsmeier–Haack reaction conditions are rearranged into novel xanthene-type compounds. All synthesized aminochromene derivatives fluoresce in organic solvents with extra large Stokes shifts (100–133 nm). It was found that compounds containing five-membered annulated aliphatic rings in methanol solution have the best spectral characteristics. These compounds have moderate quantum yields of 28.36–28.94%, and extra large Stokes shifts 106 and 115 nm.

Full text of DOI:10.1016/j.tet.2019.04.007

Accepted Manuscript
Vilsmeier-Haack reagent: An efficient reagent for the transformation of substituted
1,3-naphthoxazines into xanthene-type dyes
Oleg K. Farat, Ivan V. Ananyev, Svetlana A. Varenichenko, Anatoliy L. Tatarets,
Victor I. Markov
PII:
S0040-4020(19)30397-7
https://doi.org/10.1016/j.tet.2019.04.007
TET 30252
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 11 January 2019
Revised Date: 31 March 2019
Accepted Date: 2 April 2019
Please cite this article as: Farat OK, Ananyev IV, Varenichenko SA, Tatarets AL, Markov VI, Vilsmeier-
Haack reagent: An efficient reagent for the transformation of substituted 1,3-naphthoxazines into
xanthene-type dyes, Tetrahedron (2019), doi: https://doi.org/10.1016/j.tet.2019.04.007.
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ACCEPTED MANUSCRIPT
Vilsmeier-Haack reagent: an efficient reagent for the
transformation of substituted 1,3-naphthoxazines into xanthene-
type dyes
a
b,c
d
e
Oleg K. Farat *, Ivan V. Ananyev , Svetlana A. Varenichenko , Anatoliy L. Tatarets , Victor I.
d
Markov
a
Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow,
Russian Federation
b
A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences,
1
19991 Moscow, Russian Federation
c
Plekhanov Russian University of Economics, 117997 Moscow, Russian Federation
d
Ukrainian State University of Chemical Technology, 49005 Dnipro, Ukraine
e
State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of
Ukraine, 61001 Kharkiv, Ukraine
Corresponding author: faratok@mail.ru
R
R
CHO
O
O
O
POCl /DMF
3
NH
R
R
16
17
18
16
17
18
CHO
CHO
OHC
N
12 examples
NMe2
Vis
UV
16
17
18
R=H

ACCEPTED MANUSCRIPT
Vilsmeier-Haack reagent: an efficient reagent for the
transformation of substituted 1,3-naphthoxazines into xanthene-
type dyes
a
b,c
d
e
Oleg K. Farat *, Ivan V. Ananyev , Svetlana A. Varenichenko , Anatoliy L. Tatarets , Victor I.
d
Markov
a
Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow,
Russian Federation
b
A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences,
1
19991 Moscow, Russian Federation
c
Plekhanov Russian University of Economics, 117997 Moscow, Russian Federation
d
Ukrainian State University of Chemical Technology, 49005 Dnipro, Ukraine
e
State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of
Ukraine, 61001 Kharkiv, Ukraine
Corresponding author: faratok@mail.ru
Keywords: Vilsmeier–Haack reagent; rearrangement; heterocyclic dye; Stokes
shift; crystal structure
Abstract
Derivatives of 1,3-naphthoxazines containing from five to seven-membered
spiro ring – under Vilsmeier–Haack reaction conditions are rearranged into novel
xanthene-type compounds. All synthesized aminochromene derivatives fluoresce
in organic solvents with extra large Stokes shifts (100–133 nm). It was found that
compounds containing five-membered annulated aliphatic rings in methanol
solution have the best spectral characteristics. These compounds have moderate
quantum yields of 28.36–28.94%, and extra large Stokes shifts 106 and 115 nm.
1

ACCEPTED MANUSCRIPT
Introduction
The importance of the Vilsmeier–Haack reagent in organic chemistry is
unquestionable, not only for introduction of CHO group into the activated aromatic
and heteroaromatic compounds, but also for various condensations, cyclizations
1
–6
and rearrangements (for example, see reviews ). In our previous works, it was
shown that, under the action of this reagent, the substituted spiroquinazolones are
7
,8
rearranged into hydroacridine derivatives (Pathways A and B),
and the
9
substituted spiropyrimidones – are converted into quinazolines (Pathway C). It
was also found that substituted 1,3-benzoxazines in the Vilsmeier-Haack reaction
1
0,11
conditions are transformed into formylxanthene derivatives (Pathway D)
(
Scheme 1). The reaction we discovered (Pathway D) allows obtaining novel
functionally substituted fluorophores, capable of being used as low molecular
weight building blocks for organic synthesis. These xanthene derivatives fluoresce
in acetonitrile solution with large Stokes shifts and moderate fluorescence quantum
yields. Introduction of formylxanthenes into Knoevenagel condensation and Schiff
12,13
reaction gave dyes with high extinction coefficients.
Similar formylxanthene
1
4–18
derivatives are used for the synthesis of near-infrared fluorescent dyes.
This article presents the rearrangement of substituted 1,3-naphthoxazines
into xanthene-type compounds under the action of Vilsmeier-Haack reagent, as
well as the investigation of the spectral properties of the novel compounds. The
increase in the number of examples of newly discovered rearrangement is
interesting not only from the point of view of obtaining new fluorophores, but also
for expanding the synthetic arsenal of organic chemistry methods.
2

ACCEPTED MANUSCRIPT
O
O
H
NH2
N
O
+
H
N
CH3
N
CH3
H
N
H C
3
NH
Pathway C
H
N
N
O
O
H
O
NH
CH
+
N
3
O
N
Pathway D
O
Cl
-
H C
+
3
N
N
OPOCl2
Pathway A
O
H
H
H
O
H
NH
O
N
N
N
H C
CH3
3
NH
Pathway B
O
N
N
N
N
Scheme 1. Examples of the use of Vilsmeier–Haack reagent in our previous studies.
Synthesis and identification
The next step in our research was the synthesis and investigation of the
reactivity of substituted 1,3-naphthoxazines under the conditions of the Vilsmeier-
1
0
Haack reaction. Spiroderivatives 4–15 were obtained by the known method — by
the interaction of the corresponding amides with cyclic ketones under acid
catalysis with the removal of formed reaction water (Scheme 2). The structures of
1
13
the obtained compounds were determined by H, C NMR and FTIR
spectroscopy, as well as mass spectrometry. Compounds 7–9 and 13–15 were
found to form as a mixture of stereoisomers.
3

ACCEPTED MANUSCRIPT
R
O
R
OH
NH2
pTsOH
H O
O
O
+
-
2
NH
R
R
O
2
3
. R=H
. R=i-Pr
4
-15
Scheme 2. Synthesis of substituted naphthoxazines
Table 1. Synthesized naphthoxazines (Structures and yields of substituted naphthoxazines
obtained) via Scheme 2.
O
O
O
O
O
O
NH
NH
NH
4
(80%)
5 (92%)
6 (78%)
Me
O
O
O
O
O
NH
NH
NH
7
(88%)
8
(91%)
9 (85%)
O
O
O
O
NH
NH
NH
10 (75%)
O
11 (93%)
12 (85%) O
O
Me
O
O
O
NH
NH
NH
13 (88%)
14 (80%)
O
O
15 (85%)
O
1
9
Amide 2 was obtained through the corresponding acid chloride according
2
0
to the method and amide 3 was synthesized by alkylation of commercially
available 3-hydroxy-2-naphthoic acid with isopropyl alcohol in concentrated
sulfuric acid, followed by amidation (Scheme 3). Alternatively, amide 3 can also
be obtained by alkylation of unsubstituted amide 2 under similar conditions.
4

ACCEPTED MANUSCRIPT
1
. SOCl , DMF
OH
2
OH
2
i-PrOH, H SO4
2. aq. NH , CH Cl
3 2 2
3
CO H
2
CO H
2
1
Scheme 3. Synthesis of substituted 3-hydroxy-2-naphthoic acid 1
The structure of acid 1 was confirmed by a complex of spectral analysis
1
13
methods, including H, C NMR and FTIR spectroscopy, as well as mass
spectrometry. To determine the exact structure of product 1 experiments of two-
dimensional heteronuclear correlation of HSQC and HMBC were performed in
1
13
addition. Some important H- C HMBC correlations for compound 1 are
presented on Figure 1. Full set of data of heteronuclear correlations is given in the
Supplementary materials.
H C
CH3
H
3
H
H
O
H
O
H C
3
H
CH3
H
H
O
H
1
13
Figure 1. Some important H- C HMBC correlations for acid 1
The interaction of the spirans 4–15 with the Vilsmeier–Haack reagent at 80°
C for 1.5 h yielded previously unknown xanthene derivatives 16–27. The reaction
products were isolated via the intermediate perchlorate salts, which were then
introduced into the hydrolysis reaction. Compounds 7–9 and 13–15 were used for
further reactions as a mixture of isomers.
-
ClO Me
4
+
R
R
N
R
CHO
1
. POCl /DMF
3
Me
O
O
O
O
NaOH, H O
2
.NaClO /H O
2
4
2
NH
R
R
R
N
NMe2
5
N
4-15
1
6-27
NMe2

ACCEPTED MANUSCRIPT
Scheme 4. Synthesis of xanthene-type compounds
Table 2. Structures and synthetic yields of xanthene-type compounds obtained by the
reactions of Scheme 4
CHO
CHO
OHC
O
O
N
O
1
6 (65%)
N
17 (75%)
8 (70%)
N
1
NMe2
NMe2
NMe2
CHO
CHO
CHO
O
O
O
Me
19 (60%)
N
20 (78%)
N
21 (74%)
N
NMe2
NMe2
NMe2
CHO
OHC
CHO
O
N
O
N
O
22 (55%)
23 (70%)
N
2
4 (65%)
NMe2
NMe2
NMe2
CHO
CHO
CHO
O
O
O
N
Me
2
5 (55%)
N
26 (50%)
N
27 (45%)
NMe2
NMe2
NMe2
1
The structures of the synthesized compounds were confirmed by H NMR,
1
3
C NMR, FTIR spectroscopy and mass spectrometric data. In addition, X-ray
1
13
diffraction analysis was performed for compounds 16–18. The H and C NMR
spectra of these compounds have a characteristic signal of the formyl group at
~10.3 ppm and ~187 ppm, respectively. An analysis of bond lengths of compounds
1
6–18 shows a significant elongation of carbonyl bonds up to 1.2388 (18)–1.2407
2
1
(14) Å compared with the average C=O bond length in aldehydes – 1.192 Å.
-
1
Signals at ~1630 cm are observed in the IR spectra, corresponding to the signals
from CHO groups conjugated with an electron-donating group, which position are
6

ACCEPTED MANUSCRIPT
closer to amide carbonyl group than to aldehydes by the values of the
wavenumber.
It is worth to mention that dimethyl substituted naphthoxazine 28 under the
similar conditions gives diformyl derivative 29.
1
. POCl /DMF
3
CHO
CHO
CH3
O
O
2. NaClO /H O
4 2
O
CH3 3. NaOH/H O
2
NH
28
NH2
9 (54%)
2
1
The structure of the synthesized compound 29 was confirmed by H NMR,
1
3
C NMR, FTIR spectroscopy and mass spectrometric data.
The signals of the
1
NH protons in the H NMR experiment in DMSO at 20 °C, give two singlet
2
signals at 9.17 ppm and 8.95 ppm, which, along with the signals from the protons
CHO at 9.95 ppm, indicates a strong conjugation between the amino and the
1
formyl groups. Temperature increase in the H NMR experiment to 60 °C leads to
a coalescence of the signals of NH group protons, appeared in the form of a
2
broadened singlet at 9.00 ppm (See supplementary materials). The obtained data
indicate that formally single bond C-N acquires the character of a partially double
10
bond, which are in agreement with the previous data for similar compounds.
The single crystal X-ray diffraction studies of compounds 16–18 (Fig. 2–4)
revealed that the size of the aliphatic cycle affects both intra- and intermolecular
structure peculiarities. In 16 the compact aliphatic ring exhibits a nearly flat
conformation with maximal displacements of atoms from mean-squared plane
being less than 0.037 Å. At the same time, the sofa and boat conformations are
observed for the aliphatic cycles in 17 and 18, respectively (Fig. 5). The latter,
together with the different rigidity of cycles, results in a slight variation of bond
length distribution. For instance, the C-C bond between aliphatic cycle and
carbonyl group and the annulated C-C bonds lengthen (on ca. 0.02 Å) upon an
increase of the aliphatic ring. The most pronounced difference is observed for the
rotation of the dimethylamidine fragment with respect to the xanthene moiety.
Namely, the C5-C6-N1-C18 torsion angle in 16 (Fig. 2) is equal to 41.8(2)°, while
7

ACCEPTED MANUSCRIPT
its analogs in 17 and 18 correspond to the rotation in the opposite direction
(290.5(2)° and 308.0(1)°, respectively). The absolute values of these angles are in
11
line with our recent DFT studies concerning the interplay between steric effects
and dimethylamidine conjugation in similar systems. One should note that the
dimethylamidine fragment rotation in 16–18 is evidently caused by the
conformation of the aliphatic cycle. Namely, in 16 and 17 the methylene groups of
the latter participate in the CH…π intermolecular contacts which bound molecules
into centrosymmetric dimers. These dimers, in turn, are always additionally
stabilized by CH…O interactions between the CH group of the dimethylamidine
fragment and the carbonyl oxygen atom (Fig. 6). A similar situation is observed in
1
8 where above-mentioned methylene and CH groups form intermolecular contacts
with the same oxygen atom (Fig. 7). The different rotation of the dimethylamidine
fragment in the compounds 16–18 can be also explained by other effects of crystal
packing. Namely, the dimethylamidine fragment in 16 participates in five
shortened CH…O contacts with the carbonyl oxygen atom of three neighboring
molecules (C…O distances 3.41–3.65Å, CHO angles 147–175° with normalized
hydrogen atoms). In compounds 17 and 18 less directional and weaker CH…π and
H…H contacts are also observed for the dimethylamidine fragment, while it forms
a smaller number of CH…O contacts (one in 17 with the C…O distance equals 3.2
Å, two in 18 with the C…O distances equal 3.33 and 3.52 Å).
Figure 2. ORTEPs of the molecule 16 with thermal ellipsoids at 50% level for all non-hydrogen
atoms.
8

ACCEPTED MANUSCRIPT
Figure 3. ORTEPs of the molecule 17 with thermal ellipsoids at 50% level for all non-hydrogen
atoms.
Figure 4. ORTEPs of the molecule 18 with thermal ellipsoids at 50% level for all non-hydrogen
atoms.
Figure 5. Conformations of aliphatic cycles in 17 (left) and 18 (right)
9

ACCEPTED MANUSCRIPT
Figure 6. Centrosymmetric dimers of molecules 16 (top) and 17 (bottom) in crystal
stabilized by CH…π and CH…O interactions (dashed lines).
Figure 7. The dimer of molecules 18 in crystal stabilized by CH…O interactions of
carbonyl oxygen atom with the aliphatic cycle and the dimethylamidine fragment (dashed lines).
Spectral properties
Absorption and emission properties of dyes 16–18 were obtained in five
solvents of various polarities to evaluate the effect of the size of the annulated
aliphatic cycles in xanthene-likes moiety of novel dyes. Normalized spectra of all
these dyes are given in Supplementary materials. The spectra of compounds 16–18
1
0

ACCEPTED MANUSCRIPT
-5
were recorded for 2.5·10 mol/L solutions. The synthesized dyes 16–18 showed
absorption and emission in the range of 424–435 nm and 524–529 nm respectively
in solvents of varying polarities (Table 3), so the compounds 16–18 are
-
1
characterized by sufficiently large Stokes shift of 4300–5590 cm (Table 3). The
size of the aliphatic cycle of the chromene moiety do not affect greatly the
extinction coefficient or position of absorption and emission. It must be noted that
the lowest extinction coefficients for these dyes are observed for solutions in
toluene. The positions of the long-wavelength absorption bands and emission
maxima of all compounds are almost independent of the physicochemical
characteristics of the solvent, which indicates that the dipole moments of these
compounds are not very large in the ground and excited states. At the same time,
large Stokes shifts evidenced about significant redistribution of the electron density
in molecules in the structurally and solvated-relaxed electronically excited state.
The highest fluorescence quantum yields are observed for compound 16, and the
lowest ones – for compound 18 in all investigated solvents. Cyclopentene
derivative 16 indicates more pronounced vibrational structure in emission spectra
as compared to cyclohexene and cycloheptene derivatives 17 and 18, respectively.
It is evidenced that flattening of molecule 16 occurs in the excited state, while the
vibrational motion of the more flexible cyclohexene and cycloheptene rings
prevents flattening of the molecule. Motion of the more flexible cyclohexene (and
even more for cycloheptene) moiety in the excited state also leads to an increase in
nonradiative energy dissipation, and as a result, to a decrease in fluorescence
quantum yields. So, the annulated five-membered aliphatic cycle in 16 is more
rigid and makes the chromophoric system more planar, as compared to the six- and
seven-membered aliphatic cycles in 17 and 18. The more pronounced vibrational
bands in the fluorescence spectra of 16 indicate the more rigid structure of this
molecule in the excited state. The highest quantum yields for dyes 16–18 are
observed in methanol solutions (Table 3). Just for these solutions the lowest
Stokes shifts were noted that means methanol leads to less energy loss upon
electron density redistribution in the excited state. Probably the reconfiguration of
1
1

ACCEPTED MANUSCRIPT
the solvation shell upon relaxation with methanol in the excited state is less
pronounced, resulting in stabilization of the excited state and an increase the
fluorescence quantum yield. Figure 8 shows the photographs of compounds 16–18
in methanol solutions under irradiation with visible and ultraviolet light (365 nm)
a
Table 3. UV-Vis absorption and emission properties of compounds 16–18 in different solvents
4
b
F
Solvent Solvent
polarity,
Compound λAbs-max λEm-max
ε
x10
λEx(nm) Ф , % Stokes
max
-
1
-1
(nm)
(nm)
(M cm )
shift,
nm/cm
-1
c
N
ET
1
6
424
425
424
426
430
426
435
435
430
424
430
425
427
430
426
540
555
524
550
550
550
535
550
550
530
555
555
548
559
559
1.27
1.85
1.89
2.43
2.31
2.58
2.85
2.52
2.15
2.62
2.31
2.20
2.80
2.24
2.44
424
425
424
426
430
426
435
435
430
424
430
425
427
430
426
1.89
1.87
0.14
116/5070
130/5510
100/4500
PhMe
0.099
0.309
0.762
0.460
0.386
17
1
1
8
6
12.77 124/5290
3.74
0.10
28.94 100/4300
7.21
0.07
16.52 106/4720
2.95
0.04
24.42 121/5170
4.90
0.07
CH Cl2
17
120/5070
124/5290
2
1
1
8
6
MeOH
MeCN
DMF
17
115/4810
120/5070
1
1
8
6
17
125/5210
130/5510
1
1
8
6
17
129/5590
133/5590
1
8
a
Absorption (λAbs-max), emission (λEm-max), excitation (λ ) maxima and extinction coefficients (εmax) were
Ex
determined.
b
22
Quantum yields (Ф ) determined at 20 °C using quinine in 0.1 M H SO (Ф =0.55) as the standard. The quantum
F
2
4
F
yields are corrected for the refractive indices of solvents and inner-filter effects.
c
23
Normalized values of solvent polarity were taken from
16
17
18
16
17 18
Vis
UV
Figure 8. Methanol solutions of compounds 16–18 upon irradiation with visible and UV
light (365 nm)
Absorption and emission spectra of compounds 19–27 were recorded in
-
5
methanol for 2.5·10 mol/L solutions The normalized absorption as well as
.
emission spectra for all nine compounds are presented in Supplementary materials.
Photophysical parameters such as molar extinction coefficients, Stokes shifts,
fluorescence quantum yields of compounds 19–27 in methanol solution were
1
2

ACCEPTED MANUSCRIPT
evaluated and represented in Table 4. It was shown that the introduction of alkyl
groups into the aromatic and aliphatic part of dyes 19–27 does not significantly
affect the absorption and emission maxima, as well as the Stokes shift and the
fluorescence quantum yield. At the same time, a decrease in the extinction
coefficient for compounds 19–27 compared with dyes 16–18 should be noted.
a
Table 4. UV-Vis absorption and emission properties of compounds 19–27 in MeOH
4
-1
b
Compound λAbs-max
nm)
λEm-max εmaxx10 (M
λEx(nm)
Ф ,
Stokes shift,
nm/cm
F
-1
-1
(
(nm)
555
555
555
538
556
553
556
558
558
cm )
1.92
1.87
1.57
2.02
1.14
1.23
1.68
1.33
1.14
%
1
2
2
2
2
2
2
2
2
9
0
1
2
3
4
5
6
7
428
430
430
432
435
429
433
429
430
428
430
430
432
435
429
433
429
430
8.14
6.52
6.11
28.36
7.33
0.05
8.22
6.22
6.14
127/5350
125/5240
125/5240
106/4560
121/5000
124/5230
123/5110
129/5390
128/5330
a
Absorption (λAbs-max), emission (λEm-max), excitation (λ ) maxima and extinction coefficients (εmax) were
Ex
determined.
b
22
Quantum yields (Ф ) determined at 20 °C using quinine in 0.1 M H SO (Ф =0.55) as the standard. The quantum
F
2
4
F
yields are corrected for the refractive indices of solvents and inner-filter effects.
Conclusion
In this work, we have synthesized and studied the spectral properties in
different solvents of aminochromene derivatives containing formylated, partially
hydrogenated five, six and seven-membered cycles. It was shown that 1,3-
naphthoxazines which contained five-, six- or seven-membered spiro rings are
rearranged into novel xanthene-type compounds during Vilsmeier–Haack reagent.
All synthesized aminochromene derivatives fluoresce in organic solvents with
extra large Stokes shifts (100–133 nm). It was found that compounds containing
five-membered annulated saturated rings in methanol solution have the best
spectral characteristics. These compounds have moderate quantum yields of 28.36–
2
8.94%, and extra large Stokes shifts 106 and 115 nm. The obtained compounds
are highly functionalized and could serve as low-molecular-weight building blocks
for organic synthesis and as organic fluorophores.
1
3

ACCEPTED MANUSCRIPT
Experimental section
Unless otherwise stated, all reagents of analytical grade were purchased from
1
commercial suppliers and used without any further purification. The H NMR and
1
3
C NMR spectra were performed on a Bruker Avance II 400 spectrometer (400.13
1
13
MHz and 100.62 MHz for H and C, respectively) or Bruker Avance 600
1
13
spectrometer (600.13 MHz and 150.91 MHz for H and C, respectively) in
DMSO-d or CDCl using residual solvent peak (δ 2.50 ppm and 7.26 ppm; 39.50
6
3
1
13
1
13
ppm and 77.16 ppm for H and C, respectively) as a reference. The H and C
NMR spectra for compounds 13, 14 and 15 are presented for the predominant
isomer. The FTIR spectra were recorded in KBr pellets using a Varian 640 FT–IR
spectrometer. The UV−vis spectra were measured by a Hitachi U-1900
spectrophotometer using quartz cuvette with optical path length 10 mm, the
baseline was corrected relative to the solvent absorption. Excitation and emission
luminescence spectra were collected using Hitachi F-7000 spectrofluorometer for
solutions in different solvents placed in a standart quartz cuvette with an optical
path length 10 mm, 90° geometry. The EI mass spectra were recorded on Kratos
MS 30 with direct injection of the sample to the ionization chamber at temperature
of 250 °C with 70 eV ionizing electrons. The FAB mass spectra were recorded on
a VG7070 spectrometer. Desorption of the ions from the solution of the samples in
meta-nitrobenzyl alcohol was realized with a beam of argon atoms with energy 8
keV. Elemental analysis was performed on a LECO CHN-900 instrument. Melting
points were carried out using an Electrothermal 9100 Digital Melting Point
apparatus and were uncorrected. The control of reactions and the purity of the
obtained compounds were monitored by TLC on Merck Silica gel 60 F-254 plates
with 10:1, v/v CHCl /MeOH as eluent.
3
Synthesis
3
-Hydroxy-5,7-diisopropyl-2-naphthoic acid (1)
3
mL (0.04 mol) of i-PrOH was slowly added to 8 mL of conc. H SO with stirring
2
4
and ice-cooling. Then 2.82 g (0.015 mol) of 3-hydroxy-2-naphthoic acid was
added to the obtained solution and heated at 80° C for 1.5 h. Reaction mixture was
1
4

ACCEPTED MANUSCRIPT
left for 12 h at room temperature, poured onto ice, the acid 1 was filtered off, dried
and crystallized from n-hexane. The yield is 3.10 g (76%), mp 162–164 °C. FTIR
-
1
1
(
KBr pellets, ν, cm ): 3302 (O-H), 3059, 2960–2872, 1660 (C=O). H NMR (600
MHz, CDCl , ppm): δ = 11.07 (1H, br s, OH), 9.98 (1H, s, OH), 8.60 (1H, s, 1-H
3
Ar), 7.60 (1H, s, 4-H Ar), 7.53 (1H, s, 8-H Ar), 7.40 (1H, s, 6-H Ar), 3.56–3.63
3
(
1H, m, CH(CH ) ), 3.01–3.07 (1H, m, CH(CH ) ), 1.41 (6H, d, J=6.9 Hz,
3
2
3 2
3
13
CH(CH ) ), 1.36 (6H, d, J=6.9 Hz, CH(CH ) ). C NMR (151 MHz, CDCl ,
3
2
3
2
3
ppm): δ = 175.1, 155.9, 144.4, 143.3, 135.8, 134.5, 128.2, 126.1, 123.6, 112.4,
+
1
08.4, 34.2, 28.9, 23.9, 23.4. Mass spectrum (EI), m/z (I , %): 272 [М] (56).
rel
Found, %: C 75.11; H 7.57. C H O . Calculated, %: C 74.97; H 7.40.
1
7
20
3
3
-Hydroxy-2-naphthamide (2)
To a suspension of 3-hydroxy-2-naphthoic acid (5 g, 0.027 mol) in 225 mL CH Cl
2
2
were added a few drops of DMF and 3.65 mL (0.05 mol) of SOCl . The mixture
2
was refluxed with stirring for 1 h. Then the solvent was evaporated on a rotary
evaporator to dryness. The obtained acid chloride was dissolved in 60 ml of
CH Cl , and the resulting solution was slowly added dropwise with vigorous
2
2
stirring to a mixture of concentrated NH OH (50 mL) and CH Cl (30 mL). The
4
2
2
mixture was vigorously stirred at room temperature for 24 h and then acidified to a
pH 3 with 10% HCl. The precipitate formed was filtered off, washed with sodium
carbonate solution, water and dried in air. Yield: 3.58 g (72%), mp 216–218 °C
20
-1
(
lit. mp 216–217 °C). FTIR (KBr pellets, ν, cm ): 3464 (O-H), 3344 (as NH ),
2
1
3
228 (sy NH ), 3051, 2924–2852, 1645 (C=O). H NMR (400 MHz, DMSO-d ,
2
6
ppm): δ = 12.53 (1H, br s, OH), 8.66 (1H, br s) and 8.08 (1H, br s, NH ), 8.57 (1H,
2
3
3
s, 1-H Ar), 7.82 (1H, d, J=8.1 Hz, 8-H Ar), 7.73 (1H, d, J=8.3 Hz, 5-H Ar), 7.49
3
13
(
1H, t, J=7.6 Hz, 6-H Ar), 7.32–7.35 (1H, m, 7-H Ar), 7.27 (1H, s, 4-H Ar). C
NMR (100 MHz, DMSO-d , ppm): δ = 171.4, 156.5, 136.4, 129.9, 128.8, 128.4,
6
1
26.5, 125.8, 123.6, 117.4, 110.8.
3
-Hydroxy-5,7-diisopropyl-2-naphthamide (3)
1
5

ACCEPTED MANUSCRIPT
Amide 3 was obtained by procedure similar to compound 2. Yield 70%, yellow
-
1
powder, mp 144–146°C (i-PrOH). FTIR (KBr pellets, ν, cm ): 3413 (O-H), 3356
1
(
as NH ), 3199 (sy NH ), 3034, 2960–2870, 1649 (C=O). H NMR (600 MHz,
2
2
CDCl , ppm): δ = 11.60 (1H, br s, OH), 8.00 (1H, s, Ar), 7.55 (1H, s, Ar), 7.40
3
(
1H, s, Ar), 7.32 (1H, s, Ar), 6.62 (1H, br s) and 6.31 (1H, br s, NH ), 3.51–3.58
2
3
(
1H, m, CH(CH ) ), 2.95–3.01 (1H, m, CH(CH ) ), 1.37 (6H, d, J=6.9 Hz,
3
2
3 2
3
13
CH(CH ) ), 1.31 (6H, d, J=6.9 Hz, CH(CH ) ). C NMR (151 MHz, CDCl ,
3
2
3
2
3
ppm): δ = 172.8, 156.4, 144.2, 143.2, 134.5, 128.8, 127.7, 125.0, 122.8, 115.1,
+
1
08.9, 34.1, 28.9, 23.9, 23.4. Mass spectrum (EI), m/z (I , %): 271 [М] (60).
rel
Found, %: C 75.40; H 7.89; N 5.23. C H NO . Calculated, %: C 75.25; H 7.80; N
1
7
21
2
5
.16.
Synthesis of Spirans 4–15 (General method)
A mixture of the corresponding salicylamide (0.010 mol), ketone (0.012 mol) and
p-TsOH×H O (0.03 mol) in toluene (45 mL) was refluxed for 8 h with continuous
2
removal of water with a Dean–Stark trap. А solvent was evaporated to dryness
under reduced pressure, the solid residue was washed with 5% aq. NaOH solution
and filtered off.
Spiro[cyclopentane-1,2'-naphtho[2,3-e][1,3]oxazin]-4'(3'H)-one (4)
24
Yield 80%, yellow powder, mp 220–222°C (DMF) (lit. mp 221–222 °C). FTIR
-
1
1
(
(
(
KBr pellets, ν, cm ): 3186 (N-H), 3066, 2958–2873, 1684 (C=O), 1633. H NMR
600 MHz, CDCl /DMSO-d , ppm): δ = 8.77 (1H, s, NH), 8.36 (1H, s, Ar), 7.82
3
6
3
3
3
1H, d, J=8.1 Hz, Ar), 7.68 (1H, d, J=8.2 Hz, Ar), 7.44 (1H, t, J=7.1 Hz, Ar),
3
7
.32 (1H, d, J=7.1 Hz, Ar), 7.23 (1H, s, Ar), 2.07–2.12 (2H, m), 1.70–1.86 (6H,
1
3
m). C NMR (151 MHz, CDCl /DMSO-d , ppm): δ = 162.0, 151.8, 136.1, 128.7,
3
6
1
28.3, 127.9, 126.1, 124.2, 118.7, 111.9, 96.9, 37.5, 22.2.
Spiro[cyclohexane-1,2'-naphtho[2,3-e][1,3]oxazin]-4'(3'H)-one (5)
1
6

ACCEPTED MANUSCRIPT
Yield 92%, yellow powder, mp 232–234°C (DMF) (lit. mp 233–234 °C). FTIR
24
-
1
1
(
KBr pellets, ν, cm ): 3178 (N-H), 3062, 2940–2848, 1685 (C=O), 1635. H NMR
(
400 MHz, DMSO-d , ppm): δ = 8.90 (1H, s, NH), 8.43 (1H, s, Ar), 8.02 (1H, d,
6
3
3
3
J=8.2 Hz, Ar), 7.84 (1H, d, J=8.2 Hz, Ar), 7.55 (1H, t, J=7.0 Hz, Ar), 7.45 (1H,
3
s, Ar), 7.42 (1H, d, J=7.1 Hz, Ar), 1.96–2.02 (2H, m), 1.56–1.66 (7H, m), 1.20–
1
3
1
1
.26 (1H, m). C NMR (100 MHz, DMSO-d , ppm): δ = 161.0, 151.3, 136.4,
6
29.3, 128.5, 128.4, 128.3, 126.6, 124.7, 119.1, 112.1, 87.4, 35.8, 24.2, 21.5.
Spiro[cycloheptane-1,2'-naphtho[2,3-e][1,3]oxazin]-4'(3'H)-one (6)
-
1
Yield 78%, yellow powder, mp 273–274 °C (DMF). FTIR (KBr pellets, ν, cm ):
1
3
174 (N-H), 3062, 2931–2854, 1670 (C=O), 1633. H NMR (600 MHz, DMSO-d ,
6
3
ppm): δ = 8.93 (1H, s, NH), 8.41 (1H, s, Ar), 8.01 (1H, d, J=7.9 Hz, Ar), 7.82
3
3
(
1H, d, J=8.0 Hz, Ar), 7.54 (1H, t, J=7.1 Hz, Ar), 7.39–7.42 (2H, m, Ar), 2.08–
1
3
2
.13 (2H, m), 1.91–1.97 (2H, m), 1.44–1.86 (8H, m). C NMR (151 MHz,
DMSO-d , ppm): δ = 160.9, 151.5, 136.4, 129.3, 128.5, 128.4, 128.3, 126.5, 124.7,
6
+
1
18.9, 112.1, 91.6, 39.7, 28.4, 20.9. Mass spectrum (EI), m/z (I , %): 281 [М]
rel
(
28). Found, %: C 76.94; H 6.92; N 5.05. C H NO . Calculated, %: C 76.84; H
1
8
19
2
6
.81; N 4.98.
4
-Methylspiro[cyclohexane-1,2'-naphtho[2,3-e][1,3]oxazin]-4'(3'H)-one (7)
-
1
Yield 88%, yellow powder, mp 250–260 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
178 (N-H), 3064, 2943–2864, 1676 (C=O), 1635. H NMR (600 MHz, CDCl ,
3
ppm): δ = 8.52 (1H, s, Ar), 7.88–7.90 (1H, m, Ar), 7.85 (0.64H, s, NH), 7.71–7.74
1H, m, Ar), 7.60 (0.26H, s, NH), 7.45–7.52 (1H, m, Ar), 7.34–7.42 (1.80H, m,
Ar), 7.30 (0.20H, s, Ar), 2.27–2.30 (2H, m), 2.14–2.16 (0.50H, m), 1.31–1.85
(
1
3
(
6.50H, m), 0.95–1.01 (3H, m). C NMR (151 MHz, CDCl , ppm): δ = 162.3,
3
1
3
7
50.7, 136.1, 128.6, 128.5, 128.1, 127.6, 125.8, 123.9, 117.4, 111.8, 86.4, 35.3,
+
0.2, 29.4, 21.0. Mass spectrum (EI), m/z (I , %): 281 [М] (35). Found, %: C
rel
6.97; H 6.91; N 5.09. C H NO . Calculated, %: C 76.84; H 6.81; N 4.98.
1
8
19
2
1
7

ACCEPTED MANUSCRIPT
-tert-Butylspiro[cyclohexane-1,2'-naphtho[2,3-e][1,3]oxazin]-4'(3'H)-one (8)
4
-
1
Yield 91%, yellow powder, mp 250–256 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
186 (N-H), 3066, 2956–2866, 1682 (C=O), 1635. H NMR (400 MHz, DMSO-d ,
6
ppm): δ = 9.02 (0.24H, br s, NH), 8.78 (0.76H, br s, NH), 8.43 (1H, s, Ar), 8.01
3
3
3
(
1H, d, J=8.2 Hz, Ar), 7.85 (0.73H, d, J=8.2 Hz, Ar), 7.81 (0.27H, d, J=8.4 Hz,
3
Ar), 7.54 (1H, t, J=7.4 Hz, Ar), 7.38–7.43 (2H, m, Ar), 2.07–2.20 (2.50H, m),
13
1
.57–1.64 (4H, m), 1.39–1.45 (2.50H, m), 0.87 (9H, s). C NMR (100 MHz,
DMSO-d , ppm): δ = 161.6, 161.5, 152.2, 151.6, 136.7, 129.6, 128.9, 128.8, 128.7,
6
1
3
27.0, 126.9, 125.1, 125.0, 119.5, 112.5, 112.3, 88.5, 87.4, 46.7, 46.3, 36.8, 36.3,
+
2.5, 32.4, 27.9, 27.8, 27.4, 22.8, 22.6. Mass spectrum (EI), m/z (I , %): 323 [М]
rel
(
48). Found, %: C 78.12; H 7.91; N 4.45. C H NO . Calculated, %: C 77.98; H
2
1
25
2
7
.79; N 4.33.
4
4
-(1,1-Dimethylpropyl)spiro[cyclohexane-1,2'-naphtho[2,3-e][1,3]oxazin]-
'(3'H)-one (9)
-
1
Yield 85%, yellow powder, mp 225–231 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
176 (N-H), 3060, 2960–2868, 1685 (C=O), 1635. H NMR (600 MHz, CDCl ,
3
3
ppm): δ = 8.54 (1H, s, Ar), 7.95 (0.78H, br s, NH), 7.90 (1H, d, J=7.6 Hz, Ar),
3
3
7
.73–7.75 (1.22H, m, Ar, NH), 7.52 (1H, t, J=6.4 Hz, Ar), 7.40 (1H, t, J=6.6 Hz,
Ar), 7.36 (0.78H, s, Ar), 7.31 (0.22H, s, Ar), 2.27–2.36 (2H, m), 1.55–1.64 (5.50H,
1
3
m), 1.23–1.32 (3.50H, m), 0.78–0.89 (9H, m). C NMR (151 MHz, CDCl , ppm):
3
δ = 162.4, 150.7, 136.1, 128.6, 128.5, 158.1, 127.6, 125.8, 123.9, 117.8, 111.8,
4
2.9, 25.9, 33.8, 31.8, 23.4, 21.7, 21.5, 7.3. Mass spectrum (EI), m/z (I , %): 337
rel
+
[
М] (43). Found, %: C 78.45; H 8.11; N 4.21. C H NO . Calculated, %: C
22
27
2
7
8.30; H 8.06; N 4.15.
7
',9'-Diisopropylspiro[cyclopentane-1,2'-naphtho[2,3-e][1,3]oxazin]-4'(3'H)-one
(
10)
-
1
Yield 75%, yellow powder, mp 112–115 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
198 (N-H), 3066, 2960–2872, 1682 (C=O), 1631. H NMR (600 MHz, CDCl ,
3
1
8

ACCEPTED MANUSCRIPT
ppm): δ = 8.49 (1H. s, Ar), 7.57 (1H, s, Ar), 7.54 (2H, br s, Ar, NH), 7.38 (1H, s,
Ar), 3.56–3.64 (1H, m, CH(CH ) ), 3.02–3.08 (1H, m, CH(CH ) ), 1.83–1.92 (8H,
3
2
3 2
3
3
m, 4CH ), 1.41 (6H, d, J=6.8 Hz, CH(CH ) ), 1.34 (6H, d, J=6.8 Hz, CH(CH ) ).
2
3
2
3 2
1
3
C NMR (151 MHz, CDCl , ppm): δ = 162.9, 150.9, 144.1, 142.6, 132.9, 129.1,
3
1
29.0, 123.8, 122.8, 116.9, 107.8, 96.4, 37.6, 33.3, 28.0, 22.9, 22.5, 22.0. Mass
+
spectrum (EI), m/z (I , %): 337 [М] (56). Found, %: C 78.50; H 8.16; N 4.28.
rel
C H NO . Calculated, %: C 78.30; H 8.06; N 4.15.
2
2
27
2
7
',9'-Diisopropylspiro[cyclohexane-1,2'-naphtho[2,3-e][1,3]oxazin]-4'(3'H)-one
(
11)
-
1
Yield 93%, yellow powder, mp 188–190 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
182 (N-H), 3064, 2958–2864, 1676 (C=O), 1633. H NMR (600 MHz, DMSO-d ,
6
ppm): δ = 8.81 (1H, s, NH), 8.34 (1H, s, Ar), 7.67 (1H, s, Ar), 7.52 (1H, s, Ar),
7
1
.38 (1H, s, Ar), 3.56–3.62 (1H, m, CH(CH ) ), 2.97–3.05 (1H, m, CH(CH ) ),
3
2
3 2
3
.99–2.02 (2H, m), 1.58–1.65 (7H, m), 1.32 (6H, d, J=6.7 Hz, CH(CH ) ), 1.27
3
2
3
13
(
6H, d, J=6.9 Hz, CH(CH ) ), 1.25 (1H, m). C NMR (151 MHz, DMSO-
3
2
d6,ppm): δ = 161.0, 150.8, 144.1, 142.8, 132.8, 129.2, 128.7, 124.0, 123.3, 118.4,
1
07.8, 87.2, 35.8, 33.5, 28.2, 24.2, 23.7, 23.2, 21.5. Mass spectrum (EI), m/z (Irel,
+
%
): 351 [М] (96). Found, %: C 78.66; H 8.36; N 4.04. C H NO . Calculated, %:
23
29
2
C 78.60; H 8.32; N 3.98.
7
',9'-Diisopropylspiro[cycloheptane-1,2'-naphtho[2,3-e][1,3]oxazin]-4'(3'H)-one
(
12)
-
1
Yield 85%, yellow powder, mp 97–100 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
192 (N-H), 3066, 2960–2866, 1678 (C=O), 1631. H NMR (600 MHz, CDCl ,
3
ppm): δ = 8.47 (1H. s, Ar), 7.56 (1H, s, Ar), 7.54 (2H, br s, Ar, NH), 7.37 (1H, s,
Ar), 3.58–3.66 (1H, m, CH(CH ) ), 3.02–3.06 (1H, m, CH(CH ) ), 2.27–2.31 (2H,
3
2
3 2
3
m), 1.98–2.02 (2H, m), 1.68–1.76 (6H, m), 1.50–1.56 (2H, m), 1.41 (6H, d, J=6.9
3
13
Hz, CH(CH ) ), 1.34 (6H, d, J=6.9 Hz, CH(CH ) ). C NMR (151 MHz, CDCl ,
3
2
3
2
3
ppm): δ = 162.1, 150.4, 143.9, 142.5, 133.0, 128.8, 123.7, 122.8, 116.8, 112.3,
1
9

ACCEPTED MANUSCRIPT
1
07.7, 90.9, 43.0, 39.4, 33.2, 27.7, 22.9, 22.5, 20.5. Mass spectrum (EI), m/z (I ,
rel
+
%
): 365 [М] (41). Found, %: C 79.03; H 8.68; N 3.90. C H NO . Calculated, %:
24
31
2
C 78.87; H 8.55; N 3.83.
7
4
',9'-Diisopropyl-4-methylspiro[cyclohexane-1,2'-naphtho[2,3-e][1,3]oxazin]-
'(3'H)-one (13)
-
1
Yield 88%, yellow powder, mp 247–254 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
170 (N-H), 3062, 2956–2870, 1678 (C=O), 1633. H NMR (600 MHz, CDCl ,
3
ppm): δ = 8.49 (1H, s, Ar), 7.58 (2H, s, Ar), 7.46 (1H, br s, Ar, NH), 7.37 (1H, s,
Ar), 3.60–3.66 (1H, m, CH(CH ) ), 3.02–3.06 (1H, m, CH(CH ) ), 2.28–2.32 (3H,
3
2
3 2
3
3
m), 1.46–1.68 (6H, m), 1.43 (6H, d, J=6.8 Hz, CH(CH ) ), 1.35 (6H, d, J=6.9 Hz,
3
2
1
3
CH(CH ) ), 1.00–1.03 (3H, m, CH ). C NMR (151 MHz, CDCl , ppm): δ =
3
2
3
3
1
3
62.4, 150.2, 144.0, 142.6, 132.9, 129.0, 124.9, 123.7, 122.8, 117.0, 107.8, 86.4,
5.3, 33.3, 30.3, 29.4, 28.0, 23.0, 22.6, 21.0. Mass spectrum (EI), m/z (I , %): 365
rel
+
[
М] (47). Found, %: C 79.04; H 8.64; N 3.87. C H NO . Calculated, %: C
24
31
2
7
8.87; H 8.55; N 3.83.
7
4
',9'-Diisopropyl-4-tert-butylspiro[cyclohexane-1,2'-naphtho[2,3-e][1,3]oxazin]-
'(3'H)-one (14)
-
1
Yield 80%, yellow powder, mp 130–136 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
199 (N-H), 3070, 2960–2870, 1678 (C=O), 1631. H NMR (400 MHz, CDCl ,
3
ppm): δ = 8.47 (1H, s, Ar), 7.76 (1H, br s, NH), 7.55 (1H, s, Ar), 7.54 (1H, s, Ar),
7
2
.37 (1H, s, Ar), 3.58–3.64 (1H, m, CH(CH ) ), 3.02–3.06 (1H, m, CH(CH ) ),
3
2
3 2
3
.28–2.32 (3H, m), 1.46–1.68 (6H, m), 1.43 (6H, d, J=6.8 Hz, CH(CH ) ), 1.35
3
2
3
13
(
6H, d, J=6.9 Hz, CH(CH ) ), 0.91 (9H, s, t-Bu). C NMR (100 MHz, CDCl ,
3
2
3
ppm): δ = 162.6, 150.0, 144.1, 142.7, 132.9, 128.8, 128.7, 124.7, 122.8, 117.0,
1
07.8, 86.4, 35.3, 33.3, 30.3, 29.4, 28.0, 26.7, 23.0, 22.6, 21.0. Mass spectrum (EI),
+
m/z (I , %): 407 [М] (52). Found, %: C 79.84; H 9.28; N 3.56. C H NO .
rel
27 37
2
Calculated, %: C 79.56; H 9.15; N 3.44.
2
0

ACCEPTED MANUSCRIPT
',9'-Diisopropyl-4-(1,1-dimethylpropyl)spiro[cyclohexane-1,2'-naphtho[2,3-
7
e][1,3]oxazin]-4'(3'H)-one (15)
-
1
Yield 85%, yellow powder, mp 105–115 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
3
190 (N-H), 3068, 2960–2872, 1680 (C=O), 1631. H NMR (400 MHz, CDCl ,
3
ppm): δ = 8.48 (1H. s, Ar), 7.76 (1H, br s, NH), 7.56 (1H, s, Ar), 7.54 (1H, s, Ar),
7
2
.37 (1H, s, Ar), 3.59–3.64 (1H, m, CH(CH ) ), 3.02–3.06 (1H, m, CH(CH ) ),
3
2
3 2
3
.28–2.32 (3H, m), 1.46–1.68 (8H, m), 1.43 (6H, d, J=6.8 Hz, CH(CH ) ), 1.35
3
2
3
13
(
6H, d, J=6.9 Hz, CH(CH ) ), 0.91 (6H, m), 0.82–0.84 (3H, m). C NMR (100
3
2
MHz, CDCl , ppm): δ = 163.0, 151.2, 144.9, 143.5, 132.7, 128.6, 128.3, 124.2,
3
1
8
3
23.2, 117.0, 107.8, 86.4, 35.3, 33.3, 30.3, 29.4, 28.2, 26.4, 23.1, 22.7, 22.5, 21.0,
+
.2. Mass spectrum (EI), m/z (I ,%): 421 [М] (46). Found, %: C 79.95; H 9.48; N
rel
.42. C H NO . Calculated, %: C 79.77; H 9.32; N 3.32.
27
37
2
Synthesis of compounds 16–27 (General Method)
Compound 4 (2.53 g, 0.01 mol) was added to the Vilsmeier reagent prepared from
POСl (2.75 mL, 0.03 mol) and DMF (4.61 mL, 0.06 mol) with ice cooling. The
3
reaction mixture was stirred and heated on a water bath at 80 °C for 1.5 h. Then the
reaction mixture was cooled to 10 °C and treated with an ice-cold 15% aq. solution
of NaClO (10 mL). The precipitate of the organic salt was filtered off, dried and
4
washed with toluene. The organic salt was dissolved in hot DMF (5 mL). To the
obtained solution, an aqueous 15 % NaOH solution (1.5 mL) was added and the
mixture was stirred vigorously at 60–75 °C for 5 min. The precipitated solid of
compound 16 was filtered off. If no solid was formed, the solution was cooled to
room temperature and water was added to crystallize the product.
Similarly to 16 compounds 17–27 and 29 were obtained.
N'-(3-Formyl-1,2-dihydrobenzo[g]cyclopenta[b]chromen-11-yl)-N,N-
dimethylimidoformamide (16)
-
1
Yield 65%, yellow powder, mp 215–216 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
1
626 (CHO). H NMR (400 MHz, DMSO-d , ppm): δ = 9.90 (1H, s, CHO), 8.23
6
2
1

ACCEPTED MANUSCRIPT
3
3
(
1H, s), 8.13 (1H, s, Ar), 7.95 (1H, d, J=8.2 Hz, Ar), 7.87 (1H, d, J=7.7 Hz, Ar),
3
3
7
.69 (1H, s, Ar), 7.50 (1H, t, J=7.3 Hz, Ar), 7.44 (1H, t, J=7.5 Hz, Ar), 3.11 (6H,
1
s, NMe ), 2.84–2.87 (2H, m, CH ), 2.55–2.58 (2H, m, CH ). H NMR (600 MHz,
2
2
2
3
CDCl , ppm): δ = 10.01 (1H, s, CHO), 7.82 (1H, d, J=8.2 Hz, Ar), 7.76 (1H, s,
3
3
3
Ar), 7.75 (1H, d, J=8.2 Hz, Ar), 7.51 (1H, s, Ar), 7.45 (1H, t, J=7.2 Hz, Ar), 7.39
3
(
1H, t, J=7.6 Hz, Ar), 3.18 (3H, s, Me), 3.10 (3H, s, Me), 2.81–2.84 (2H, m, CH ),
2
1
3
2
1
1
.73–2.76 (2H, m, CH ). C NMR (151 MHz, CDCl , ppm): δ = 182.6, 165.5,
2
3
53.3, 149.6, 133.0, 129.7, 127.4, 126.2, 126.1, 126.0, 124.3, 122.3, 121.7, 120.0,
14.2, 110.6, 39.6, 33.5, 23.0, 22.6. Mass spectrum (FAB), m/z (I , %): 319
rel
+
[
М+H] (28). Found, %: C 75.60; H 5.75; N 8.87. C H N O . Calculated, %: C
2
0
18
2
2
7
5.45; H 5.70; N 8.80.
N'-(4-Formyl-2,3-dihydro-1H-benzo[b]xanthen-12-yl)-N,N-
dimethylimidoformamide (17)
-
1
Yield 75%, yellow powder, mp 195–196 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
1
636 (CHO). H NMR (400 MHz, DMSO-d , ppm): δ = 10.25 (1H, s, CHO), 8.05
6
3
3
(
1H, s), 7.95 (1H, d, J=8.1 Hz, Ar), 7.84 (1H, d, J=8.2 Hz, Ar), 7.76 (1H, s, Ar),
3
3
7
.66 (1H, s, Ar), 7.50 (1H, t, J=7.0 Hz, Ar), 7.41 (1H, t, J=7.0 Hz, Ar), 3.09 (3H,
3
3
s, Me), 3.08 (3H, s, Me), 2.54 (2H, t, J=6.1 Hz, CH ), 2.31 (2H, t, J=5.9 Hz,
2
1
CH ), 1.56–1.62 (2H, m, CH ). H NMR (600 MHz, CDCl , ppm): δ = 10.35 (1H,
2
2
3
3
3
s, CHO), 7.92 (1H, s, Ar), 7.80 (1H, d, J=8.2 Hz, Ar), 7.72 (1H, d, J=8.2 Hz, Ar),
3
7
.42–7.75 (3H, m, Ar), 7.35 (1H, t, J=7.0 Hz, Ar), 3.17 (3H, s, Me), 3.08 (3H, s,
3
3
Me), 2.56 (2H, t, J=6.1 Hz, CH ), 2.45 (2H, t, J=6.0 Hz, CH ), 1.66–1.70 (2H, m,
2
2
1
3
CH ). C NMR (151 MHz, CDCl , ppm): δ = 187.3, 162.5, 153.8, 149.9, 146.3,
2
3
1
3
34.4, 130.2, 128.4, 127.2, 126.9, 124.9, 123.6, 121.8, 113.6, 112.4, 110.8, 40.4,
+
4.5, 25.6, 21.5, 20.9. Mass spectrum (EI), m/z (I , %): 332 [М] (67). Found, %:
rel
C 75.98; H 6.12; N 8.49. C H N O . Calculated, %: C 75.88; H 6.06; N 8.43.
2
1
20
2
2
N'-(7-Formyl-8,9,10,11-tetrahydrobenzo[g]cyclohepta[b]chromen-12-yl)-N,N-
dimethylimidoformamide (18)
2
2

ACCEPTED MANUSCRIPT
-
1
Yield 70%, yellow powder, mp 180–183 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
1
642 (CHO). H NMR (600 MHz, CDCl , ppm): δ = 10.39 (1H, s, CHO), 7.92
3
3
3
3
(
1H, s), 7.79 (1H, d, J=8.2 Hz, Ar), 7.71 (1H, d, J=8.2 Hz, Ar), 7.42 (1H, t, J=7.4
3
Hz, Ar), 7.39 (2H, s, Ar), 7.34 (1H, t, J=7.5 Hz, Ar), 3.17 (3H, s, Me), 3.09 (3H, s,
13
Me), 2.63–2.66 (4H, m, 2CH ), 1.76–1.82 (4H, m, 2CH ). C NMR (151 MHz,
2
2
CDCl , ppm): δ = 185.5, 166.5, 153.6, 150.0, 149.8, 134.6, 130.0, 128.5, 127.2,
3
1
26.9, 124.8, 123.9, 121.6, 117.9, 117.0, 110.5, 40.4, 34.6, 28.1, 26.1, 25.8, 20.0.
+
Mass spectrum (EI), m/z (I , %): 346 [М] (77). Found, %: C 76.40; H 6.52; N
rel
8
.18. C H N O . Calculated, %: C 76.28; H 6.40; N 8.09.
22
22
2
2
N'-(4-Formyl-2-methyl-2,3-dihydro-1H-benzo[b]xanthen-12-yl)-N,N-
dimethylimidoformamide (19)
-
1
Yield 60%, yellow powder, mp 217–220 °C (DMF). FTIR (KBr pellets, ν, cm ):
1
1
639 (CHO). H NMR (600 MHz, CDCl , ppm): δ = 10.34 (1H, s, CHO), 7.92
3
3
3
(
1H, s), 7.81 (1H, d, J=8.1 Hz, Ar), 7.72 (1H, d, J=8.2 Hz, Ar), 7.41–7.46 (3H,
3
m, Ar), 7.36 (1H, t, J=7.1 Hz, Ar), 3.19 (3H, s, Me), 3.10 (3H, s, Me), 2.70–2.77
(
2H, m, CH ), 2.02 (1H, dd, J=15.6 Hz, J=11.2 Hz), 1.90 (1H, dd, J=16.2 Hz,
2
3
13
J=10.2 Hz), 1.70–1.77 (1H, m, CH), 1.06 (3H, d, J=6.5 Hz, Me). C NMR (151
MHz, CDCl , ppm): δ = 187.3, 162.4, 153.7, 149.8, 145.6, 134.4, 130.1, 128.4,
3
1
2
27.2, 126.9, 124.9, 123.6, 121.7, 113.4, 111.7, 110.8, 40.4, 34.5, 33.5, 29.4, 27.0,
+
1.2. Mass spectrum (EI), m/z (I , %): 346 [М] (81). Found, %: C 76.43; H 6.54;
rel
N 8.18. C H N O . Calculated, %: C 76.28; H 6.40; N 8.09.
2
2
22
2
2
N'-(2-tert-Butyl-4-formyl-2,3-dihydro-1H-benzo[b]xanthen-12-yl)-N,N-
dimethylimidoformamide (20)
-
1
Yield 78%, yellow powder, mp 215–217 °C (DMF). FTIR (KBr pellets, ν, cm ):
1
1
635 (CHO). H NMR (600 MHz, CDCl , ppm): δ = 10.36 (1H, s, CHO), 7.91
3
3
3
(
1H, s), 7.81 (1H, d, J=8.3 Hz, Ar), 7.74 (1H, d, J=8.1 Hz, Ar), 7.43–7.46 (3H,
m, Ar), 7.35–7.39 (1H, m, Ar), 3.20 (3H, s, Me), 3.11 (3H, s, Me), 2.92 (1H, d,
J=15.2 Hz), 2.82 (1H, d, J=15.9 Hz), 1.90–1.99 (2H, m, CH ), 1.66–1.73 (1H, m,
2
2
3

ACCEPTED MANUSCRIPT
13
CH), 0.97 (9H, s, t-Bu). C NMR (151 MHz, CDCl , ppm): δ = 187.5, 162.4,
3
1
1
53.8, 149.9, 146.3, 134.4, 130.1, 128.4, 127.2, 126.9, 124.9, 123.5, 121.8, 114.7,
12.5, 110.9, 46.7, 40.4, 34.6, 32.4, 27.5, 26.5, 22.7. Mass spectrum (EI), m/z (Irel,
+
%
): 388 [М] (86). Found, %: C 77.45; H 7.36; N 7.29. C H N O . Calculated,
2
5
28
2
2
%: C 77.29; H 7.26; N 7.21.
N'-[2-(1,1-Dimethylpropyl)-4-formyl-2,3-dihydro-1H-benzo[b]xanthen-12-yl]-
N,N-dimethylimidoformamide (21)
-
1
Yield 74%, yellow powder, mp 190–193 °C (DMF). FTIR (KBr pellets, ν, cm ):
1
1
635 (CHO). H NMR (600 MHz, CDCl , ppm): δ = 10.35 (1H, s, CHO), 7.91
3
3
3
(
1H, s), 7.81 (1H, d, J=8.1 Hz, Ar), 7.73 (1H, d, J=8.2 Hz, Ar), 7.41–7.46 (3H,
3
m, Ar), 7.37 (1H, t, J=7.4 Hz, Ar), 3.19 (3H, s, Me), 3.11 (3H, s, Me), 2.83–2.88
(
1H, m), 2.73–2.78 (1H, m), 1.91–1.98 (2H, m, CH ), 1.26–1.45 (3H, m), 0.89
2
3
13
(
6H, s), 0.83 (3H, t, J=7.5 Hz). C NMR (151 MHz, CDCl , ppm): δ = 187.4,
3
1
1
62.4, 153.8, 149.8, 146.4, 134.3, 130.1, 128.4, 127.2, 126.9, 124.9, 123.5, 121.8,
14.7, 112.6, 110.9, 40.4, 39.7, 34.7, 32.7, 26.0, 24.2, 24.1, 22.3, 8.3. Mass
+
spectrum (EI), m/z (I , %): 402 [М] (75). Found, %: C 77.73; H 7.62; N 7.06.
rel
C H N O . Calculated, %: C 77.58; H 7.51; N 6.96.
2
6
30
2
2
N'-(3-Formyl-6,8-diisopropyl-1,2-dihydrobenzo[g]cyclopenta[b]chromen-11-yl)-
N,N-dimethylimidoformamide (22)
-
1
Yield 55%, yellow powder, mp 235–238 °C (i-PrOH). FTIR (KBr pellets, ν, cm ):
1
1
626 (CHO). H NMR (400 MHz, DMSO-d , ppm): δ = 10.02 (1H, s, CHO), 8.07
6
(1H, s), 7.76 (1H, s, Ar), 7.69 (1H, s, Ar), 7.53 (1H, s, Ar), 7.36 (1H, s, Ar), 3.57–
3
2
.66 (1H, m, CH(CH ) ), 3.20 (3H, s), 3.11 (3H, s), 3.02–3.04 (1H, m, CH(CH ) ),
3
2
3 2
3
.83–2.87 (2H, m, CH ), 2.55–2.58 (2H, m, CH ), 1.34 (6H, d, J=6.8 Hz,
2
2
3
CH(CH ) ), 1.28 (6H, d, J=6.9 Hz, CH(CH ) ). Mass spectrum (EI), m/z (I , %):
3
2
3
2
rel
+
4
7
02 [М] (83). Found, %: C 77.71; H 7.58; N 7.03. C H N O . Calculated, %: C
2
6
30
2
2
7.58; H 7.51; N 6.96.
2
4

ACCEPTED MANUSCRIPT
N'-(4-Formyl-7,9-diisopropyl-2,3-dihydro-1H-benzo[b]xanthen-12-yl)-N,N-
dimethylimidoformamide (23)
-
1
Yield 70%, yellow powder, mp 218–220 °C (MeOH). FTIR (KBr pellets, ν, cm ):
1
1
627 (CHO). H NMR (400 MHz, DMSO-d , ppm): δ = 10.32 (1H, s, CHO), 8.01
6
(1H, s), 7.82 (1H, s, Ar), 7.77 (1H, s, Ar), 7.62 (1H, s, Ar), 7.33 (1H, s, Ar), 3.61–
3
.66 (1H, m, CH(CH ) ), 3.09 (3H, s, Me), 3.08 (3H, s, Me), 2.97–3.04 (1H, m,
3
2
3
3
CH(CH ) ), 2.57 (2H, t, J=6.0 Hz, CH ), 2.32 (2H, t, J=5.7 Hz, CH ), 1.56–1.62
3
2
2
2
3
3
(
2H, m, CH ), 1.34 (6H, d, J=6.8 Hz, CH(CH ) ), 1.28 (6H, d, J=6.9 Hz,
2
3 2
13
CH(CH ) ). C NMR (400 MHz, DMSO-d /CF CO D, ppm): δ = 187.3, 159.3,
3
2
6
3
2
1
1
57.3, 148.9, 146.1, 144.2, 131.6, 131.5, 131.1, 126.3, 124.7, 124.5, 123.1, 118.9,
16.5, 107.7, 44.1, 37.8, 34.2, 28.9, 25.6, 24.0, 23.6, 21.4, 20.2. Mass spectrum
+
(
FAB), m/z (I , %): 417 [М+H] (100). Found, %: C 76.03; H 7.80; N 6.76.
rel
C H N O . Calculated, %: C 77.85; H 7.74; N 6.72.
2
7
32
2
2
N'-(7-Formyl-2,4-diisopropyl-8,9,10,11-tetrahydrobenzo[g]cyclohepta[b]chro-
men-12-yl)-N,N-dimethylimidoformamide (24)
-
1
Yield 65%, yellow powder, mp 121–124 °C (MeOH). FTIR (KBr pellets, ν, cm ):
1
1
635 (CHO). H NMR (400 MHz, CDCl , ppm): δ = 10.44 (1H, s, CHO), 7.88
3
(1H, s), 7.66 (1H, s, Ar), 7.48 (1H, s, Ar), 7.41 (1H, s, Ar), 7.29 (1H, s, Ar), 3.61–
3
.66 (1H, m, CH(CH ) ), 3.20 (3H, s, Me), 3.10 (3H, s, Me), 3.02–3.06 (1H, m,
3
2
CH(CH ) ), 2.63–2.66 (4H, m, 2CH ), 1.76–1.82 (4H, m, 2CH ), 1.43 (6H, d,
3
2
2
2
3
3
13
J=6.8 Hz, CH(CH ) ), 1.35 (6H, d, J=6.9 Hz, CH(CH ) ). C NMR (100 MHz,
3
2
3 2
CDCl , ppm): δ = 187.1, 162.6, 153.4, 149.4, 145.5, 144.9, 143.6, 131.0, 130.6,
3
1
2
24.0, 123.1, 122.5, 121.0, 113.4, 111.5, 107.0, 40.4, 34.5, 34.2, 33.5, 29.6, 29.3,
+
7.5, 24.0, 23.6, 22.9. Mass spectrum (EI), m/z (I , %): 430 [М] (73). Found, %:
rel
C 78.33; H 8.09; N 6.61. C H N O . Calculated, %: C 78.10; H 7.96; N 6.51.
2
8
34
2
2
N'-(4-Formyl-7,9-diisopropyl-2-methyl-2,3-dihydro-1H-benzo[b]xanthen-12-yl)-
N,N-dimethylimidoformamide (25)
2
5

ACCEPTED MANUSCRIPT
-
1
Yield 55%, yellow powder, mp 191–194 °C (MeOH). FTIR (KBr pellets, ν, cm ):
1
1
630 (CHO). H NMR (600 MHz, CDCl , ppm): δ = 10.40 (1H, s, CHO), 7.88
3
(1H, s), 7.70 (1H, s, Ar), 7.49 (1H, s, Ar), 7.42 (1H, s, Ar), 7.31 (1H, s, Ar), 3.61–
3
.66 (1H, m, CH(CH ) ), 3.20 (3H, s, Me), 3.10 (3H, s, Me), 3.02–3.06 (1H, m,
3
2
CH(CH ) ), 2.74–2.80 (2H, m, CH ), 2.05 (1H, dd, J=15.3 Hz, J=11.3 Hz), 1.93
3
2
2
3
(
1H, dd, J=15.9 Hz, J=10.3 Hz), 1.70–1.77 (1H, m, CH), 1.43 (6H, d, J=6.8 Hz,
3
3
13
CH(CH ) ), 1.35 (6H, d, J=6.9 Hz, CH(CH ) ), 1.08 (3H, d, J=6.5 Hz, Me). C
3
2
3 2
NMR (151 MHz, CDCl , ppm): δ = 187.3, 162.8, 153.6, 149.6, 145.8, 145.0,
3
1
3
43.8, 131.2, 130.9, 124.0, 123.4, 122.6, 121.0, 113.4, 111.5, 107.0, 40.4, 34.5,
4.3, 33.5, 29.5, 29.0, 27.1, 24.0, 23.6, 21.3. Mass spectrum (EI), m/z (I , %): 430
rel
+
[
М] (81). Found, %: C 78.26; H 8.05; N 6.58. C H N O . Calculated, %: C
2
8
34
2
2
7
8.10; H 7.96; N 6.51.
N'-(2-tert-Butyl-4-formyl-7,9-diisopropyl-2,3-dihydro-1H-benzo[b]xanthen-12-yl)-
N,N-dimethylimidoformamide (26)
-
1
Yield 50%, yellow powder, mp 139–142 °C (MeOH). FTIR (KBr pellets, ν, cm ):
1
1
633 (CHO). H NMR (600 MHz, CDCl , ppm): δ = 10.38 (1H, s, CHO), 7.85
3
(1H, s), 7.70 (1H, s, Ar), 7.48 (1H, s, Ar), 7.42 (1H, s, Ar), 7.30 (1H, s, Ar), 3.60–
3
.66 (1H, m, CH(CH ) ), 3.20 (3H, s, Me), 3.10 (3H, s, Me), 3.00–3.05 (1H, m,
3
2
CH(CH ) ), 2.92–2.95 (1H, m), 2.81–2.85 (1H, m), 1.92–1.99 (3H, m), 1.43 (6H,
3
2
3
3
d, J=6.8 Hz, CH(CH ) ), 1.35 (6H, d, J=6.9 Hz, CH(CH ) ), 0.95 (9H, s, t-Bu).
3
2
3 2
+
Mass spectrum (EI), m/z (I , %): 472 [М] (74). Found, %: C 78.90; H 8.68; N
rel
6
.03. C H N O . Calculated, %: C 78.77; H 8.53; N 5.93.
31
40
2
2
N'-(2-(1,1-Dimethylpropyl)-4-formyl-7,9-diisopropyl-2,3-dihydro-1H-
benzo[b]xanthen-12-yl)-N,N-dimethylimidoformamide (27)
-
1
Yield 45%, yellow powder, mp 126–129 °C (MeOH). FTIR (KBr pellets, ν, cm ):
1
1
634 (CHO). H NMR (600 MHz, CDCl , ppm): δ = 10.39 (1H, s, CHO), 7.85
3
(1H, s), 7.70 (1H, s, Ar), 7.48 (1H, s, Ar), 7.42 (1H, s, Ar), 7.30 (1H, s, Ar), 3.60–
3
.66 (1H, m, CH(CH ) ), 3.19 (3H, s, Me), 3.09 (3H, s, Me), 3.00–3.05 (1H, m,
3
2
2
6

ACCEPTED MANUSCRIPT
CH(CH ) ), 2.87–2.90 (1H, m), 2.76–2.81 (1H, m), 1.94–1.98 (2H, m), 1.54–1.58
3
2
3
3
(
1H, m), 1.43 (6H, d, J=6.8 Hz, CH(CH ) ), 1.35 (6H, d, J=6.9 Hz, CH(CH ) ),
3
2
3 2
3
13
0
1
1
2
7
.90 (6H, s), 0.85 (3H, d, J=6.5 Hz, CH ). C NMR (151 MHz, CDCl , ppm): δ =
2
3
86.7, 162.2, 153.0, 149.0, 145.9, 144.4, 143.2, 130.6, 129.3, 123.3, 122.0, 120.4,
20.0, 113.4, 111.5, 107.0, 40.4, 34.5, 34.3, 33.5, 29.5, 29.0, 27.1, 26.2, 24.0, 22.0,
+
3.6, 21.3, 7.7. Mass spectrum (EI), m/z (I , %): 486 [М] (79). Found, %: C
rel
9.23; H 8.88; N 5.90. C H N O . Calculated, %: C 78.97; H 8.70; N 5.76.
3
1
40
2
2
2
,2-Dimethyl-2,3-dihydro-4H-naphtho[2,3-e][1,3]oxazin-4-one (28)
2
4
Compound 28 was obtained by the known procedure. Yield 62%, white powder,
1
mp 220–222 °C. H NMR (400 MHz, DMSO-d , ppm): δ = 8.91 (1H, s, NH), 8.44
6
3
3
(
1H, s, Ar), 8.03 (1H, d, J=8.2 Hz, Ar), 7.83 (1H, d, J=8.3 Hz, Ar), 7.55 (1H, t,
3
J=7.5 Hz, Ar), 7.40–7.44 (2H, m, Ar), 1.56 (6H, s, 2Me).
(4-Amino-2H-benzo[g]chromen-2-ylidene)malonaldehyde (29)
-
1
Yield 54%, yellow powder, mp 232–234 °C (MeOH). FTIR (KBr pellets, ν, cm ):
1
3
307 (NH ), 3032, 2923–2865, 1649 (C=O), 1574. H NMR (400 MHz, 20 °C,
2
DMSO-d , ppm): δ = 9.95 (2H, s, CHO), 9.17 (1H, s) and 8.95 (1H, s, NH ), 8.84
6
2
3
3
(
1H, s, Ar), 8.15 (1H, s, Ar), 8.04 (1H, d, J=8.3 Hz, Ar), 7.98 (1H, d, J=8.4 Hz,
3
3
1
Ar), 7.79 (1H, s, Ar), 7.68 (1H, t, J=7.0 Hz, Ar), 7.59 (1H, t, J=8.0 Hz, Ar). H
NMR (400 MHz, 60 °C, DMSO-d , ppm): δ = 9.95 (2H, s, CHO), 9.00 (2H, br s,
6
3
NH ), 8.85 (1H, s, Ar), 8.14 (1H, s, Ar), 8.04 (1H, d, J=8.3 Hz, Ar), 7.99 (1H, d,
2
3
3
3
J=8.4 Hz, Ar), 7.79 (1H, s, Ar), 7.68 (1H, t, J=7.0 Hz, Ar), 7.59 (1H, t, J=8.0
1
3
Hz, Ar). C NMR (100 MHz, DMSO-d , ppm): δ = 186.1, 167.9, 156.3, 148.7,
6
1
35.2, 129.5, 129.0, 128.6, 127.2, 126.4, 124.1, 114.3, 114.0, 107.4, 90.8. Mass
+
spectrum (FAB), m/z (I , %): 266 [М+H] (14). Found, %: C 72.51; H 4.25; N
rel
5
.34. C H NO . Calculated, %: C 72.45; H 4.18; N 5.28.
16
11
3
X-ray diffraction study
2
7

ACCEPTED MANUSCRIPT
Crystals of 16 (C H N O , Mr = 318.36) are monoclinic, space group P2 /c, at
2
0
18
2
2
1
1
20K: a = 11.7875(6) Å, b = 6.1475(3) Å, c = 21.3522(11) Å, β = 96.5170(10)°, V
3
–
3
-1
=
1537.26(13) Å , Z = 4, d = 1.376 g/cm , µ(MoKa) = 0.090 mm , F(000) =
calc
6
72. Intensities of 19768 reflections were measured with a Bruker APEX 2 Duo
diffractometer (CCD detector) [l(MoKa) = 0.71073Å, ω-scans, 2q<60°] and 4484
independent reflections [R =0.0592] were used in further refinement. The
int
structure was solved by direct method and refined by the full-matrix least-squares
2
technique against F in the anisotropic-isotropic approximation. The H(C) atom
positions were calculated, these atoms were refined in the isotropic approximation
within the riding model. For 16, the refinement converged to wR = 0.1348 and
2
GOF = 1.028 for all independent reflections (R = 0.0487 was calculated against F
1
for 3088 observed reflections with I>2s(I)). Crystal data were deposited at
Cambridge Crystal Database, deposition number CCDC 1874393.
Crystals of 17 (C H N O , Mr = 332.39) are monoclinic, space group P2 /c, at
2
1
20
2
2
1
1
20K: a = 15.755(2) Å, b = 9.0624(13) Å, c = 12.5984(19) Å, β = 107.711(4)°, V
3
–
3
-1
=
1713.6(4) Å , Z = 4, d = 1.288 g/cm , µ(MoKa) = 0.084 mm , F(000) = 704.
calc
Intensities of 14127 reflections were measured with a Bruker APEX 2 Duo
diffractometer (CCD detector) [l(MoKa) = 0.71073Å, ω-scans, 2q<61°] and 5069
independent reflections [R =0.0559] were used in further refinement. The
int
structure was solved by direct method and refined by the full-matrix least-squares
2
technique against F in the anisotropic-isotropic approximation. The H(C) atom
positions were calculated, these atoms were refined in the isotropic approximation
within the riding model. For 17, the refinement converged to wR = 0.1432 and
2
GOF = 0.986 for all independent reflections (R = 0.0553 was calculated against F
1
for 3048 observed reflections with I>2s(I)). Crystal data were deposited at
Cambridge Crystal Database, deposition number CCDC 1874392.
Crystals of 18 (C H N O , Mr = 346.41) are monoclinic, space group P2 /n, at
22
22
2
2
1
1
20K: a = 8.1416(4) Å, b = 16.8250(8) Å, c = 13.0219(6) Å, β = 93.2860(10)°, V
2
8