Reaction of 4-hydroxycoumarin with 2-acetyloxiranes

Article abstract of DOI:10.1134/S1070428013100163

The reaction of 4-hydroxycoumarin with 2-acetyloxiranes in dimethylformamide in the presence of triethylamine gave 2,3-dihydro-4H-furo[3,2- c]chromen-4-ones which were converted into 4H-furo[3,2-c]-chromen-4-one derivatives as a result of dehydration or f

Full text of DOI:10.1134/S1070428013100163

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2013, Vol. 49, No. 10, pp. 1497–1501. © Pleiades Publishing, Ltd., 2013.
Original Russian Text © I.A. Os’kina, A.Ya. Tikhonov, I.Yu. Bagryanskaya, Yu.V. Gatilov, O.S. Fedorova, 2013, published in Zhurnal Organicheskoi Khimii,
2
013, Vol. 49, No. 10, pp. 1517–1521.
Reaction of 4-Hydroxycoumarin with 2-Acetyloxiranes
I. A. Os’kina , A. Ya. Tikhonov , I. Yu. Bagryanskaya , Yu. V. Gatilov , and O. S. Fedorova
a
a
a
a
b
a
Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences,
pr. Akademika Lavrent’eva 9, Novosibirsk, 630090 Russia
e-mail: oi@nioch.nsc.ru
b
Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences,
Novosibirsk, Russia
Received May 4, 2013
Abstract—The reaction of 4-hydroxycoumarin with 2-acetyloxiranes in dimethylformamide in the presence of
triethylamine gave 2,3-dihydro-4H-furo[3,2-c]chromen-4-ones which were converted into 4H-furo[3,2-c]-
chromen-4-one derivatives as a result of dehydration or fragmentation.
DOI: 10.1134/S1070428013100163
Furocoumarins occupy an important place among
phenyloxirane in dimethylformamide in the presence
of triethylamine at room temperature to give 3-hy-
droxy-2-[hydroxy(phenyl)methyl]-3-methyl-2,3-dihy-
dro-4H-furo[3,2-c]chromen-4-one (II). With a view to
estimate the scope of this reaction, in the present work
we examined the reaction of 4-hydroxycoumarin (I)
with 2-acetyloxiranes III and IV containing aromatic
biologically active 4-hydroxycoumarin derivatives.
They exhibit a broad spectrum of pharmacological
properties, in particular antifungal, anticoagulant, spas-
molytic, vasodilator, antitumor, etc. [1–6]. Furocou-
marins can be isolated from natural sources [7] or
prepared by synthetic methods [8–11]. Known meth-
ods of synthesis of furocoumarin derivatives are based
on C-alkylation of 4-hydroxycoumarin with α-halo
ketones or halo alkynes, followed by cyclization
1
2
(III, R = 3-ClC
H
, R = H) or aliphatic substituents
6
4
1
2
(IV, R = R = Me) in position 3 of the three-mem-
bered ring (Scheme 1).
[
9, 10], or on oxidative addition of olefins in the pres-
As with 2-acetyl-3-phenyloxirane, 4-hydroxycou-
marin (I) reacted with 2-acetyl-3-(3-chlorophenyl)-
oxirane (III) to produce 2-[(3-chlorophenyl)(hydroxy)-
ence of silver(I) salts [11]. We recently showed [12]
that 4-hydroxycoumarin (I) reacts with 2-acetyl-3-
Scheme 1.
HO
HO
1
1
R
R
R
R
2
2
OH
O
O
O
O
OH
Me
R1
Me
Et N, DMF
3
O
+
R2
–H O
2
O
Me
O
O
O
O
I
III, IV
VII, [VIII]
IX
R1
R1
O
O
R2
O
R2
OH
I
+
III, IV
VII, [VIII]
H
OH
Me
OH
Me
O
O
O
O
V
VI
1
2
1
2
6 4
III, VII, R = 3-ClC H , R = H; IV, VIII, IX, R = R = Me.
1
497

1
498
OS’KINA et al.
methyl]-3-hydroxy-3-methyl-2,3-dihydro-4H-furo-
appreciably improve it by raising the reaction tem-
perature or increasing the reaction time.
[3,2-c]chromen-4-one (VII) (Scheme 1, cf. [12]) as
a mixture of two diastereoisomers A (Fig. 1) and B at
a ratio of 3:1, which were characterized by different
melting points and spectral parameters.
No expected 3-hydroxy-2-(1-hydroxy-1-methyl-
ethyl)-3-methyl-2,3-dihydro-4H-furo[3,2-c]chromen-
The observed difference in the behavior of oxiranes
III and IV and 2-acetyl-3-phenyloxirane in the reac-
tion with 4-hydroxycoumarin (I) may be related to the
steric structure of compounds II, VII, and VIII.
Presumably, the bulkier isopropyl group in poisition 2
of 2,3-dihydrofurocoumarin VIII favors elimination of
water with formation of double C=C bond in the five-
membered ring.
We made an attempt to effect dehydration of 3-hy-
droxy-2-[hydroxy(phenyl)methyl]-3-methyl-2,3-dihy-
dro-4H-furo[3,2-c]chromen-4-one (II) by treatment
with trifluoroacetic acid at room temperature. How-
ever, instead of the expected dehydration product X,
we isolated 3-methyl-4H-furo[3,2-c]chromen-4-one
4
2
-one (VIII) was detected in the reaction of I with
-acetyl-3,3-dimethyloxirane (IV). Obviously, inter-
mediate compound VIII undergoes fast dehydration to
form 2-(1-hydroxy-1-methylethyl)-3-methyl-4H-furo-
[3,2-c]chromen-4-one (IX) (Scheme 1). The yield of
IX was lower than the yield of VII, and we failed to
Cl1
C14
C13
(
XI) which was likely to be formed as a result of
C1
C
5
fragmentation of cation C (Scheme 2). No reaction
occurred (even on heating to 50°C) when trifluoro-
acetic acid was replaced by acetic acid.
C12
C2
C8
16
C9
C7
O1
C11
C10
C9a
9
b
The structure of compounds VII (isomer A) and IX
was determined by X-ray analysis (Figs. 1, 2). The
furochromene skeleton of VII is almost planar, the
mean-square deviation of atoms from the plane being
C
C5a
C5
C6
C3
O2
C3a
C17
2
0.049 Å. The C atom deviates by 0.214 (8) Å from the
C4
plane formed by the other atoms of the furan ring.
O3
2
O4
Analogous deviation [0.178(5) Å] was observed for C
in 3-hydroxy-2-[hydroxy(phenyl)methyl]-3-methyl-
2,3-dihydro-4H-furo[3,2-c]chromen-4-one (II) [12].
On the whole, the bond lengths and bond angles in
molecules VIIA and II coincide within 3σ with the
corresponding standard values [13]. Like 3-hydroxy-2-
Fig. 1. Structure of the molecule of 2-[(3-chlorophenyl)-
(
[
hydroxy)methyl]-3-hydroxy-3-methyl-2,3-dihydro-4H-furo-
3,2-c]chromen-4-one (VII, diastereoisomer A) according to
the X-ray diffraction data. Non-hydrogen atoms are shown as
thermal vibration ellipsoids with a probability of 30%.
[
hydroxy(phenyl)methyl]-3-methyl-2,3-dihydro-4H-
furo[3,2-c]chromen-4-one (II), molecules VIIA in
crystal are packed in such a way that through channels
occupied by strongly disordered solvate hexane mole-
C12
3
C11
C10 O2
cules with an overall volume of 371.8 Å are formed.
The furochromene skeleton of molecule IX is
planar within ±0.014(2) Å. The isopropyl group is
oriented with respect to the furan ring so that the
O1
C2
C9
C9b
C8
C9a
torsion angle C C C O is equal to 8.7(3)°. The bond
lengths in molecule IX are similar to the corresponding
bond lengths in 3-[(4-bromophenyl)amino]-4H-furo-
[3,2-c]chromen-4-one [14]. Molecules IX in crystal are
packed to form stacks along the c axis due to inter-
molecular π-stacking between the aromatic rings with
an interplane distance of 3.3 Å and intercentroid dis-
tance of 3.432(2)–3.888(2) Å. The stacks are linked to
layers through several hydrogen bonds O–H···O
3
2
10
2
O3
C3
C13
C3a
C4
C7
C5a
C6
C5
O4
Fig. 2. Structure of the molecule of 2-(1-hydroxy-1-methyl-
ethyl)-3-methyl-4H-furo-[3,2-c]chromen-4-one (IX) accord-
ing to the X-ray diffraction data. Solvate water molecule is
shown. Non-hydrogen atoms are shown as thermal vibration
ellipsoids with a probability of 50%.
(
H···O 1.76–2.19 Å, ∠ OHO 160–168°) with dis-
ordered water molecules.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 10 2013

REACTION OF 4-HYDROXYCOUMARIN WITH 2-ACETYLOXIRANES
1499
Scheme 2.
HO
Ph
CF COOH
3
O
AcOH
Me
Ph
HO
Ph
O
O
O
X
Me
OH
HO
O
O
O
O
CF COOH
Me
3
II
Me
OH2
–H O, –PhCHO
2
+
–
H
O
O
O
O
C
XI
Thus the reaction of 4-hydroxycoumarin with
-acetyloxiranes leads to the formation of 2,3-dihydro-
H-furo[3,2-c]chromen-4-ones which may undergo de-
(entry nos. CCDC 931267, 931268) and are available
at www.ccdc.cam.ac.uk/data_request/cif. Slow evap-
oration of a solution of VII in hexane–acetone gave
thin lamellar needle-shaped crystals of VIIA, and we
failed to obtain single crystals of a higher quality.
Single crystals of IX were obtained by slow evapora-
tion of its solution in a mixture of petroleum ether
2
4
hydration or fragmentation to give 4H-furo[3,2-c]-
chromen-4-one derivatives.
EXPERIMENTAL
(
bp 40–70°C) with acetone.
Analytical and spectral measurements were carried
out at the Joint Chemical Service Center (Siberian
Branch, Russian Academy of Sciences). The IR spectra
were recorded on a Bruker Vector 22 spectrometer. The
UV spectra were measured on a Hewlett Packard 4853
Commercial dimethylformamide was distilled
under reduced pressure first over calcium hydride and
then over molecular sieves and was stored over molec-
ular sieves under argon. Commercial 4-hydroxycouma-
rin (I) and 3-chlorobenzaldehyde were used without
additional purification, 4-methylpent-3-en-2-one was
distilled before use, and 1-(3,3-dimethyloxiran-2-yl)-
ethanone (IV) was prepared according to the procedure
described in [17] (its physical constants coincided with
published data).
1
spectrophotometer. The H NMR spectra were ob-
tained on a Bruker AV-400 instrument from solutions
in CDCl using the residual proton signal of the
3
solvent as reference (CHCl , δ 7.26 ppm). The high-
3
resolution mass spectra were recorded on a DFS mass
spectrometer. The X-ray diffraction data for com-
pounds VIIA and IX were acquired at 296 (VIIA) or
4
-(3-Chlorophenyl)but-3-en-2-one. 3-Chlorobenz-
aldehyde, 3.6 ml (0.032 mol), was added dropwise
over a period of 10 min to a mixture of 30 ml (0.4 mol)
of acetone and 0.5 ml of 10% aqueous sodium hydrox-
ide. The mixture was stirred for 2 h at 23–25°C,
poured into 60 ml of water, neutralized with
10% aqueous HCl, and extracted with chloroform
(2×30 ml), The combined extracts were dried over
1
50 K (IX) on a Bruker Kappa ApexII CCD diffrac-
tometer [graphite monochromator, λ(MoK ) =
α
0
.71073 Å; ω,φ-scanning, 2θ < 50 (VIIA), 52° (IX)].
A correction for absorption was applied empirically
using SADABS program [15]. The structures were
solved by the direct method. The positions and tem-
perature parameters of non-hydrogen atoms were
refined by the full-matrix least-squares procedure in
anisotropic approximation. The positions of hydrogen
atoms were calculated geometrically and were refined
according to the riding model. All calculations were
performed using SHELX97 software package [16].
The CIF files for structures VIIA and IX were deposit-
ed to the Cambridge Crystallographic Data Centre
MgSO and evaporated, and the residue, 5.5 g, was
4
distilled under reduced pressure. Yield 2.2 g (38%),
1
bp 108°C (20 mm). H NMR spectrum, δ, ppm: 2.25 s
(3H, CH ), 6.55 d (1H, CH, J = 16.4 Hz), 7.19 m (2H,
3
H
arom), 7.25 m (1H, Harom), 7.28 d (1H, CH, J =
16.4 Hz), 7.35 m (1H, Harom). Found: m/z 180.0337
+
[M] . C10
H ClO. Calculated: M 180.0336.
9
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 10 2013

1
500
OS’KINA et al.
1
-[3-(3-Chlorophenyl)oxiran-2-yl]ethanone (III).
therefore, we failed to unambiguously identify atoms
therein, and their positions were refined in isotropic
approximation. The final divergence factors were
Hydrogen peroxide, 6 ml, was added to a solution of
.81 g (0.01 mol) of 4-(3-chlorophenyl)but-3-en-2-one
1
in 50 ml of methanol, and a solution of 2 g (0.05 mol)
of sodium hydroxide in 10 ml of water was then added
in portions over a period of 30 min at room tempera-
ture. The mixture was stirred for 2.5 h at 23–25°C and
extracted with chloroform (2×30 ml), and the com-
wR
2
= 0.3007 (for all reflections) and R = 0.0980 [for
1
1596 reflections with I > 2σ(I)]; goodness of fit S =
1.015. We did not succeed in improving the R factor
because of disordering of solvent molecules and large
thermal vibrations of the carbon and chlorine atoms in
the phenyl substituent.
bined extracts were dried over MgSO and evaporated.
4
1
Yield 1.8 g (92%), colorless oily substance. H NMR
–1
Diastereoisomer VIIB. IR spectrum (KBr), ν, cm :
spectrum, δ, ppm: 2.25 s (3H, CH ), 3.46 d (1H, CH,
3
3
420, 2924, 2853, 1705, 1647, 1420, 758. UV spec-
J = 1.7 Hz), 3.98 d (1H, CH, J = 1.7 Hz), 7.17 m (1H,
trum (EtOH), λ , nm (logε): 203 (4.42), 273 (3.76),
max
H
), 7.25 m (1H, H ), 7.32–7.29 m (2H, H ).
1
arom
arom
arom
2
1
85 (3.81), 308 (3.73). H NMR spectrum, δ, ppm:
+
Found: m/z 196.0287 [M] . C H ClO . Calculated:
M 196.0286.
1
0
9
2
.74 s (3H, CH ), 2.60 s (1H, OH), 4.23 d (1H, 2-H,
3
J = 10.5 Hz), 4.96 s (1H, OH), 5.07 d (1H, CH, J =
2
-[(3-Chlorophenyl)(hydroxy)methyl]-3-hy-
10.5 Hz), 7.27–7.61 m (7H, Harom), 7.78 m (1H, Harom).
+
droxy-3-methyl-2,3-dihydro-4H-furo[3,2-c]chro-
men-4-one (VII). A mixture of 0.324 g (2 mmol) of
Found: m/z 358.0605 [M] . C19
M 358.0603.
H
15ClO . Calculated:
5
4
-hydroxycoumarin (I), 0.498 g (2.53 mmol) of
2
-(1-Hydroxy-1-methylethyl)-3-methyl-4H-furo-
oxirane III, and 0.202 g (2 mmol) of triethylamine in
[
(
(
(
3,2-c]chromen-4-one (IX). a. A mixture of 1.62 g
10 mmol) of 4-hydroxycoumarin (I), 1.14 g
10 mmol) of 1-(3,3-dimethyloxiran-2-yl)ethan-1-one
IV), and 1.01 g (10 mmol) of triethylamine in 5 ml of
2
ml of DMF was stirred for 15 h at 23–25°C. The
mixture was poured into water and extracted with
chloroform (3×10 ml), the extract was washed with
water and dried over MgSO , and the aqueous phase
4
DMF was stirred for 15 h at 23–25°C. The mixture
was then poured into water and extracted with chloro-
form (2×50 ml), the extract was washed with water
was acidified with 10% aqueous HCl to isolate 80 mg
of 4-hydroxycoumarin (I). The extract was evaporated,
and the residue (0.34 g) was subjected to chromatog-
raphy on a 20×20-mm glass plate coated with silica
gel (5–40 µm) using chloroform as eluent. We thus
isolated 0.18 g (25%) of diastereoisomer A with
and dried over MgSO , and the aqueous phase was
4
acidified with 10% aqueous HCl to isolate 1.5 g of
unreacted 4-hydroxycoumarin (I). The extract was
evaporated, and the residue, 0.14 g, was subjected to
chromatography on a 20×20-mm glass plate coated
with silica gel (5–40 µm) using chloroform as eluent.
Yield 0.05 g (2%; 26%, calculated on the reacted
mp 130–132°C (from hexane–CHCl ) and 0.06 g (8%)
3
of diastereoisomer B with mp 155–156°C (from
hexane–CHCl ).
3
–
1
4
-hydroxycoumarin), mp 134–135°C (from petroleum
Diastereoisomer VIIA. IR spectrum (KBr), ν, cm :
–1
ether–CHCl , 1:1). IR spectrum (KBr), ν, cm : 3471,
3
433, 1709, 1645, 1420, 758. UV spectrum (EtOH),
3
2
978, 1749, 1715, 1184, 754. UV spectrum (EtOH),
, nm (logε): 211 (4.27), 292 (3.81), 319 (4.03).
λ
, nm (logε): 206 (4.55), 273 (3.98), 285 (4.06), 309
max
1
λ
(
3.97). H NMR spectrum, δ, ppm: 1.92 s (3H, CH ),
max
3
1
H NMR spectrum, δ, ppm: 1.72 s (6H, CH ), 2.51 s
3
.30 s (1H, OH), 3.80 d (1H, OH, J = 4.2 Hz), 4.58 d
1H, 2-H, J = 8.5 Hz), 5.17 d.d (1H, CH, J = 4.2,
.5 Hz), 7.27–7.64 m (8H, H ), 7.63 m (1H, H ).
3
(3H, CH ), 7.29 m (1H, H ), 7.39 m (1H, H ),
7
(
3
arom
arom
.45 m (1H, H
), 7.79 m (1H, H
). Found:
8
arom
arom
arom
arom
+
+
m/z 258.0885 [M] . C H O . Calculated: M 258.0887.
Found: m/z 358.0605 [M] . C H ClO . Calculated:
15 14
4
1
9
15
5
M 358.0603. X-Ray diffraction data: monoclinic crystal
b. A mixture of 0.43 g (2.65 mmol) of 4-hydroxy-
coumarin (I), 0.30 g (2.63 mmol) of oxirane IV, and
0.26 g (2.57 mmol) of triethylamine in 5 ml of DMF
was stirred for 30 h at 76°C. The mixture was poured
into water and extracted with chloroform (3×5 ml), the
system, space group P2 /n; unit cell parameters: a =
1
1
9
2.713(4), b = 7.824(2), c = 19.393(6) Å; β =
3
6.828(9)°; V = 1915.3(9) A ; Z = 4; C H O Cl·
1
9
15
5
3
–1
C H ; d = 1.543 g/cm ; μ = 0.239 mm ; T /T
=
6
14
calc
min max
0
.75/0.98. Total of 10166 reflection intensities were
measured, including 3284 independent reflections
= 0.101). Solvate hexane molecules were located
extract was washed with water and dried over MgSO ,
4
and the aqueous phase was acidified with 10% aqueous
HCl to isolate 0.40 g of unreacted 4-hydroxycoumarin
(I). The extract was evaporated, and the residue,
(R
int
inside through channels and were strongly disordered;
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 10 2013

REACTION OF 4-HYDROXYCOUMARIN WITH 2-ACETYLOXIRANES
.07 g, was subjected to chromatography on a 20×20-
1501
0
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1
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1
1
2. Os’kina, I.A., Gatilov, Yu.V., and Tikhonov, A.Ya., Russ.
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5
3 mg (86%), mp 135–136°C [9]. H NMR spectrum,
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3
arom
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+
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1
8
8
3
M 200.0468.
1
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at 25°C or heated for 5 h at 50°C.
1
1
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integration project no. 90, 2009).
vol. 69, p. 815.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 10 2013