Oxidation of aromatic compounds: XII. Regio- and stereoselective oxidative dimerization of alkyl 3-arylpropynoates in the system CF3CO 2H-CH2Cl2-PbO2

Article abstract of DOI:10.1007/s11178-005-0005-5

Regio- and stereoselective oxidative dimerization of alkyl 3-arylpropynoates in the system CF₃CO₂H-CH ₂Cl₂-PbO₂ (1-30 h, 0-20°C) leads to dialkyl (E)-2,3-bis(arylcarbonyl)-2-butene-1,4-dioates with trans arrangement of the substituents at the double bond.

Full text of DOI:10.1007/s11178-005-0005-5

Russian Journal of Organic Chemistry, Vol. 40, No. 9, 2004, pp. 1279–1283. Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 9, 2004,
pp. 1329–1333.
Original Russian Text Copyright © 2004 by Savechenkov, Vasil’ev, Rudenko.
Oxidation of Aromatic Compounds:
XII.* Regio- and Stereoselective Oxidative Dimerization of Alkyl
3
-Arylpropynoates in the System CF CO H–CH Cl –PbO
3
2
2
2
2
P. Yu. Savechenkov, A. V. Vasil’ev, and A. P. Rudenko
St. Petersburg State Academy of Forestry Engineering, Institutskii per. 5, St. Petersburg, 194021 Russia
Received January 14, 2004
Abstract—Regio- and stereoselective oxidative dimerization of alkyl 3-arylpropynoates in the system
CF CO H–CH Cl –PbO (1–30 h, 0–20°C) leads to dialkyl (E)-2,3-bis(arylcarbonyl)-2-butene-1,4-dioates with
3
2
2
2
2
trans arrangement of the substituents at the double bond.
We previously showed that one-electron oxidation
of acetylene derivatives with lead(IV) oxide in weakly
nucleophilic acidic media (HSO F, CF CO H) leads to
The structure of compounds E-IIa–E-IIi was
rigorously established by X-ray analysis and NMR
spectroscopy. X-Ray diffraction study of the product
obtained by oxidation of methyl 3-(4-methoxyphenyl)-
propynoate (Ie) showed that it has the structure of
dimethyl 2,3-bis(4-methoxybenzoyl)-2-butene-1,4-di-
oate (IIe) having E-configuration at the double C=C
bond [1]. The structure of molecule E-IIe suggests that
oxidative dimerization of alkyne Ie involves formation
of a new C–C bond between acetylenic carbon atoms
in the α-position with respect to the carbonyl group
3
3
2
formation of oxidative dimerization products [2–6].
The next step in studying reactions of this sort was
examination of stereo- and regioselectivity relations
holding in the formation of new carbon–carbon bonds
via transformations of radical cations derived from
alkyl 3-arylpropynoates [1]. The present communica-
tion reports on the oxidation of alkyl 3-arylpropyn-
oates in the system CF CO H–CH Cl –PbO .
3
2
2
2
2
(
Scheme 1). This pattern is typical of radical cations
Scheme 1 illustrates the transformation of alkyl
derived from arylpropynone systems such as esters Ia–
Ii and symmetrically substituted 1,3-diarylpropynones
which were studied by us previously [5].
3
-arylpropynoates Ia–Ii through intermediate radical
+
·
+·
cations Ia –Ii to dialkyl (E)-2,3-bis(arylcarbonyl)-2-
butene-1,4-dioates E-IIa–E-IIi, which is promoted by
the system CF COOH–CH Cl –PbO . The reaction
1
Comparison of the H NMR spectrum of dimethyl
3
2
2
2
conditions and products yields are given in Table 1.
trans-2,3-dibenzoyl-2-butene-1,4-dioate (E-IIa) with
Scheme 1.
R'
R'
α
C
CF
3
COOH–CH
2
Cl
2
–PbO
2
C
COOR
C
C
COOR
–
e
Ia–Ii
Ia –Ii
3
5
2
R'
O
C
1
4
C
COOR
α
α'
C
O
6
ROCO
C
R'
E-IIa–E-IIi
R = Me, R' = H (a), 4-Me (b), 3,4-Me
2
2
(c), 4-F (d), 4-MeO (e), 3,4-(MeO) (f); R = Et, R' = 4-MeO (g), 3-F-4-MeO (h),
4
-MeO-3-NO (i).
2
*
For communication XI, see [1].
1
070-4280/04/4009-1279 © 2004 MAIK “Nauka/Interperiodica”

1
280
SAVECHENKOV et al.
Table 1. Conditions of oxidation of alkyl 3-arylpropynoates Ia–Ii in the system CF
products E-IIa–E-IIi
3
CO
2
H–CH
2 2
Cl –PbO
2
and yields of
Amounts of reactants
PbO , mmol CF CO H, ml CH
Reaction conditions
Initial
comp. no.
Product
(yield, %)
I, mmol
2
3
2
2
Cl
2
, ml temperature, °C
time, h
Ia
Ib
Ic
Id
Ie
If
6.25
1.72
1.33
2.81
2.10
2.11
0.49
0.45
0.50
6.25
1.72
1.33
2.81
2.10
2.11
0.49
0.45
0.50
2.4
0.7
0.5
1.1
0.8
0.8
0.2
0.2
0.2
5.0
3.0
2.5
5.0
4.0
4.0
1.5
2.0
1.0
18–20
18–20
0–2
30
05
03
20
02
01
02
01
12
E-IIa (4)
E-IIb (23)
E-IIc (18)
E-IId (9)
E-IIe (55)
E-IIf (40)
E-IIg (37)
E-IIh (38)
E-IIi (19)
18–20
0–2
0–2
Ig
Ih
Ii
0–2
0–2
18–20
that reported in [7] for cis isomer Z-IIa revealed some
distinguishing features. In the H NMR spectra
{δ (MeO) = 3.84 ppm, δZ-IIa(MeO) = 3.79 ppm [7]}.
Ia
1
As follows from the data in Table 2, a similar
recorded in CDCl , the signal from the methoxy group
difference in the chemical shifts of the OCH protons,
3
2
of isomer E-IIa is located at δ 3.56 ppm (see
Experimental), while the corresponding signal of
isomer Z-IIa appears at δ 3.79 ppm [7]. The observed
difference (∆δ = 0.23 ppm) results from different
magnetically anisotropic effects of the surrounding
molecular fragments on the MeO protons in the cis and
trans isomers of IIa. Taking into account the above
specificity of the MeO signal, dimethyl esters IIb–IIf
were also assigned trans configuration at the double
bond: signals from the methoxy protons in these com-
pounds were located in the narrow range from δ 3.56
to 3.59 ppm (see Experimental and Table 2).
∆δ (OCH ) = –0.21±0.04 ppm, is observed for ethyl
E
2
esters Ig–Ii and their oxidative dimerization products
E-IIg–E-IIi.
The yield of the product and the reaction time
strongly depend on the substituents in the aromatic
ring of esters Ia–Ii. In the oxidation of methyl
3
-phenylpropynoate (Ia), the yield of dimerization
product E-IIa in 30 h was as poor as 4%. The reaction
with para-fluoro-substituted ester Id also required
a long time (20 h), and the yield of E-IId was 9%.
Introduction of alkyl (compounds Ib and Ic) or
methoxy groups (Ie–Ii) into the aromatic ring leads to
considerable shortening of the reaction time (to 1 h for
compounds If and Ih) and increase in the yield up to
40–55% (Table 1). We failed to obtain the expected
oxidative dimerization product from methyl 3-(3,5-di-
methylphenyl)propynoate (Ij). Despite complete con-
1
In the H NMR spectra of diethyl esters IIg–IIi,
magnetic anisotropy of the environment is reflected
most clearly in the positions of signals from the OCH2
protons of the ester groups. We revealed the following
relations holding in the positions of signals from the
OMe and OCH groups in the spectra of Ia–Ii and
sumption of PbO
2
(equimolar amount, 2 h, 0–2°C), we
2
E-IIa–E-IIi. The difference between the chemical
shifts of the ester methoxy protons in compounds Ia–If
and oxidation products E-IIa–E-IIf turned out to be
isolated only a small amount of tarry products. Pre-
sumably, radical cation Ij possesses an a -like highest
2
occupied molecular orbital, and the alkyne chain con-
tributes little to delocalization of the positive charge
and unpaired electron. As a result, the oxidation in-
volves methyl groups in the substrate.
+
·
constant, ∆δ (MeO) = –0.25±0.01 ppm (Table 2). For
E
example, the chemical shift of the MeO protons in
initial alkyne Ic is δ = 3.82 ppm, and the correspond-
Ic
ing value for E-IIc is δ
= 3.57 ppm; the difference
Thus alkyl 3-arylpropynoates undergo regio- and
stereoselective transformation into dialkyl (E)-2,3-bis-
(arylcarbonyl)-2-butene-1,4-dioates in the system
CF CO H–CH Cl –PbO . This reaction may be
E-IIc
∆
δ (MeO) is δ (MeO) – δ (MeO) = –0.25 ppm. The
E
E-IIc
Ic
same pattern is typical of the other pairs of compounds
Ia–If and E-IIa–E-IIf (Table 2). By contrast, the corre-
sponding difference for the cis isomer of IIa (Z-IIa)
is ∆δ (MeO) = δ (MeO) – δ (MeO) = –0.05 ppm
3
2
2
2
2
regarded as a new efficient one-pot synthesis of dif-
ficultly accessible polyfunctional compounds [7, 8].
Z
Z-IIa
Ia
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 40 No. 9 2004

OXIDATION OF AROMATIC COMPOUNDS: XII.
1281
Table 2. Chemical shifts (CDCl
3
2
) of the MeO and OCH protons in the ester fragments of compounds Ia–Ii and E-IIa–E-IIi
δ(MeO), ppm
Pairs of compounds
∆δ
E
(MeO) = δE-II(MeO)–δ
I
(MeO), ppm
I
E-II
3.56
3.56
3.57
3.59
3.56
3.56
Ia–E-IIa
Ib–E-IIb
Ic–E-IIc
Id–E-IId
Ie–E-IIe
If–E-IIf
3.84
3.82
3.82
3.83
3.81
3.81
–0.28
–0.26
–0.25
–0.24
–0.25
–0.25
E
Average value ∆δ (MeO) = –0.25±0.01
2
δ(OCH ), ppm
∆δ
E
(OCH
2
) = δE-II(OCH
2 I 2
) – δ (OCH ),
Pairs of compounds
ppm
I
E-II
4.02
4.04
4.08
Ig–E-IIg
Ih–E-IIh
Ii–E-IIi
4.26
4.26
4.25
–0.24
–0.22
–0.17
Average value ∆δ
E
(OCH
2
) = –0.21±0.04
–
1
1
EXPERIMENTAL
spectrum (CHCl
3
), ν, cm : 1700, 2220. H NMR spec-
trum (CDCl ), δ, ppm: 2.36 s (3H, Me), 3.82 s (3H,
3
1
13
The H and C NMR spectra were recorded on
OMe), 7.16 d (2H, H , J = 7.8 Hz), 7.46 d (2H,
arom
1
a Bruker AM-500 spectrometer (500 MHz for H and
Harom, J = 7.8 Hz).
1
3
1
25.76 MHz for C) using CDCl as solvent and
3
Methyl 3-(3,4-dimethylphenyl)propynoate (Ic).
internal reference (δ 7.25 ppm, δ 77.0 ppm). The IR
C
–1
mp 41–43°C. IR spectrum (CHCl ), ν, cm : 1705,
3
spectra were obtained on a Specord 75-IR instrument
1
2
220. H NMR spectrum (CDCl ), δ, ppm: 2.24 s (3H,
3
from samples prepared as solutions in CHCl and KBr
3
Me), 2.28 s (3H, Me), 3.82 s (3H, OMe), 7.12 d
1H, Harom, J = 7.7 Hz), 7.32 d (1H, Harom, J = 7.7 Hz),
.36 s (1H, Harom). Found, %: C 76.33; H 6.38.
pellets. The mass spectra (electron impact, 70 eV)
were run on an MKh-1321 mass spectrometer with
direct sample admission into the ion source (batch inlet
probe temperature 100–120°C).
(
7
+
M 188. C H O . Calculated, %: C 76.57; H 6.42.
1
2
12
2
M 188.23.
Methyl 3-arylpropynoates Ia–If and Ij were syn-
thesized by esterification of the corresponding 3-aryl-
propynoic acids with dimethyl sulfate according to the
procedure described in [9]; the acids were prepared
from the corresponding cinnamic acids as reported in
10]. Ethyl 3-arylpropynoates Ig–Ii were obtained
by reactions of aryl iodides with ethyl propynoate
11, 12]. The properties of compounds Ie and E-IIe
Methyl 3-(4-fluorophenyl)propynoate (Id).
1
mp 56–57°C. H NMR spectrum (CDCl ), δ, ppm:
3
3
8
%
.83 s (3H, OMe), 7.07 d.d (2H, H , J = 8.9,
arom
.5 Hz), 7.58 d.d (2H, Harom, J = 8.9, 5.3 Hz). Found,
+
: C 67.31; H 4.00. M 178. C H FO . Calculated,
[
10
7
2
%
: C 67.42; H 3.96. M 178.16.
Methyl 3-(3,4-dimethoxyphenyl)propynoate (If).
mp 82–84°C; published data [9]: mp 81–82°C. IR
[
and the X-ray diffraction data for E-IIe were reported
–
1
1
previously [1].
spectrum (CHCl ), ν, cm : 1695, 2210. H NMR
3
Methyl 3-phenylpropynoate (Ia). Oily substance.
spectrum (CDCl
3
), δ, ppm: 3.81 s (3H, OMe), 3.89 s
Published data [13]: bp 128°C (4 mm). IR spectrum
(3H, OMe), 3.90 s (3H, OMe), 7.05 d (1H, Harom, J =
8.4 Hz), 7.19 d (1H, Harom, J = 1.7 Hz), 7.26 d.d (1H,
–
1
1
(
(
H
CHCl ), ν, cm : 1700, 2200. H NMR spectrum
3
CDCl ), δ, ppm: 3.84 s (3H, OMe), 7.37 d.d (2H,
Harom, J = 8.4, 1.7 Hz).
3
, J = 7.5, 7.4 Hz), 7.45 t (1H, H , J = 7.4 Hz),
arom
arom
Ethyl 3-(4-methoxyphenyl)propynoate (Ig). Oily
substance. Published data [14]: bp 140°C (5 mm).
H NMR spectrum (CDCl
J = 7.2 Hz), 3.80 s (3H, OMe), 4.26 q (2H, OCH ,
7
.58 d (2H, Harom, J = 7.5 Hz) .
1
Methyl 3-(4-methylphenyl)propynoate (Ib).
mp 65–68°C; published data [13]: mp 68–70°C. IR
3
), δ, ppm: 1.32 t (3H, Me,
2
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 40 No. 9 2004

1
282
SAVECHENKOV et al.
2
J = 7.2 Hz), 6.85 d (2H, Harom, J = 8.7 Hz), 7.51 d (2H,
Harom, J = 8.7 Hz).
128.74 d.d.d (C , J = 161.1, 7.3, 6.3 Hz), 128.94 d.d
3
4
(C , J = 162.3, 7.6 Hz), 134.04 d.t (C , J = 161.5,
.2 Hz), 135.46 t (C , J = 7.2 Hz), 142.27 s (C=C),
62.84 q (C=O, ester, J = 4.0 Hz), 190.87 t (C=O,
ketone, J = 4.5 Hz). Mass spectrum, m/z (I , %): 352
3) M , 321 (2) [M – OMe] , 105 (100) [PhCO] , 77
32) [Ph] , 51 (6). Found, %: C 68.15; H 4.58. M 352.
C H O . Calculated, %: C 68.18; H 4.58. M 352.34.
1
7
1
Ethyl 3-(3-fluoro-4-methoxyphenyl)propynoate
–
1
(
1
(
(
Ih). mp 72.5–73.5°C. IR spectrum (CHCl ), ν, cm :
3
1
rel
700, 2220. H NMR spectrum (CDCl ), δ, ppm: 1.32 t
3
+
+
+
(
(
3H, Me, J = 7.2 Hz), 3.89 s (3H, OMe), 4.26 q
+
+
2H, OCH , J = 7.2 Hz), 6.91 d.d (1H, Harom, J = 8.5,
2
8
7
.5 Hz), 7.27 d.d (1H, Harom, J = 11.2, 1.9 Hz),
20 16
6
.33 d.d.d (1H, Harom, J = 8.5, 2.2, 1.9 Hz). Found, %:
Dimethyl (E)-2,3-bis(4-methylbenzoyl)-2-butene-
1,4-dioate (E-IIb). mp 224–226°C. IR spectrum
+
C 64.82; H 4.78. M 222. C H FO . Calculated, %:
1
2
11
3
–
1
1
C 64.86; H 4.99. M 222.21.
(CHCl
3
), ν, cm : 1670, 1720. H NMR spectrum
(
CDCl ), δ, ppm: 2.43 s (6H, 2Me), 3.56 s (6H,
3
Ethyl 3-(4-methoxy-3-nitrophenyl)propynoate
1
2OMe), 7.31 d (4H, H , J = 8.3 Hz), 7.88 d (4H,
arom
(
1
Ii). mp 86–87°C. H NMR spectrum (CDCl ), δ, ppm:
3
1
3
Harom, J = 8.3 Hz). C NMR spectrum (CDCl ), δ ,
3
C
.31 t (3H, Me, J = 7.2 Hz), 3.96 s (3H, OMe), 4.25 q
ppm: 21.81 q.t (Me, J = 126.7, 4.0 Hz), 53.21 q (MeO,
(
2H, OCH , J = 7.2 Hz), 7.08 d (1H, Harom, J = 8.7 Hz),
2
2
J = 148.4 Hz), 128.90 d.d (C , J = 160.2, 6.4 Hz),
7
.70 d.d (1H, Harom, J = 8.7, 2.1 Hz), 8.00 d (1H, Harom,
3
1
1
29.67 d.d.q (C , J = 159.8, 5.9, 4.7 Hz), 133.16 t (C ,
J = 2.1 Hz). Found, %: C 57.89; H 4.48; N 5.36.
4
+
J = 7.4 Hz), 142.18 s (C=C), 145.10 t.q (C , J = 6.5,
.5 Hz), 162.98 q (C=O, ester, J = 4.0 Hz), 190.57 t
C=O, ketone, J = 3.7 Hz). Mass spectrum, m/z
M 249. C H NO . Calculated, %: C 57.83; H 4.45;
12
11
5
6
N 5.62. M 249.22.
(
(
[
Methyl 3-(3,5-dimethylphenyl)propynoate (Ij).
+
+
I , %): 380 (10) M , 349 (7) [M – OMe] , 119 (100)
rel
–
1
mp 26–27°C. IR spectrum (CHCl ), ν, vm : 1700,
+
+
3
MeC H CO] , 91 (12) [MeC H ] . Found, %:
6
4
6
4
1
2
200. H NMR spectrum (CDCl ), δ, ppm: 2.30 s (6H,
+
3
C 69.60; H 5.21. M 380. C H O . Calculated, %:
C 69.46; H 5.30. M 380.40.
2
2
20
6
2
Me), 3.80 s (3H, OMe), 7.17 s (1H, Harom), 7.23 s
+
(
2H, Harom). Found, %: C 76.70; H 6.31. M 188.
Dimethyl (E)-2,3-bis(3,4-dimethylbenzoyl)-2-
butene-1,4-dioate (E-IIc). mp 218–219°C. IR spec-
C H O . Calculated, %: C 76.57; H 6.42. M 188.23.
12
12
2
Oxidation of alkyl-3-arylpropynoates Ia–Ii to
dialkyl (E)-2,3-bis(arylcarbonyl)-2-butene-1,4-di-
oates E-IIa–E-IIi. Alkyl 3-arylpropynoate Ia–Ii,
–1
1
trum (KBr), ν, cm : 1673, 1732. H NMR spectrum
(
CDCl ), δ, ppm: 2.33 s (6H, 2Me), 2.34 s (6H, 2Me)
3
3
7
.57 s (6H, 2OMe), 7.26 d (2H, H , J = 8.0 Hz),
arom
0
.45–6.25 mmol, was added at 0–20°C under vigorous
.71 d.d (2H, Harom, J = 8.0, 1.6 Hz), 7.79 d (2H, Harom
,
13
stirring to a solution of 0.2–2.4 ml of trifluoroacetic
acid in 1–5 ml of methylene chloride. Lead(IV) oxide,
J = 1.6 Hz). C NMR spectrum (CDCl ), δ , ppm:
3
C
1
9.80 q.d (Me, J = 126.7, 4.6 Hz), 20.17 q.d (Me,
0
.45–6.25 mmol, was then added, and the mixture was
J = 126.7, 4.6 Hz), 53.24 q (MeO, J = 148.8 Hz),
26.75 d.d (C , J = 160.6, 5.9 Hz), 129.55 d.d.q (C ,
J = 158.1, 5.5 Hz), 130.19 d.q (C , J = 158.5, 4.7 Hz),
33.53 d (C , J = 7.6 Hz), 137.45 m (C , J = 5.0 Hz),
42.25 s (C=C), 143.94 m (C , J = 5.0 Hz), 163.06 q
C=O, ester, J = 4.0 Hz), 190.82 t (C=O, ketone, J =
4.2 Hz). Mass spectrum, m/z (I , %): 408 (9) M , 134
(10), 133 (100) [Me C H CO] , 95 (6), 79 (9), 77 (7).
6
2
stirred for 1–30 h (Table 1). When the reaction was
complete, the mixture was poured into 50–250 ml of
chloroform. The chloroform solution was washed in
succession with water, a saturated aqueous solution of
sodium hydrogen carbonate, and water again, dried
1
5
1
3
1
1
4
(
+
over Na SO , and evaporated. The residue was sub-
2
4
rel
+
jected to column chromatography on silica gel using
petroleum ether–chloroform (40:70) as eluent. The
yields of compounds E-IIa–E-IIi were determined
from the weights of fractions isolated by chromatog-
raphy (Table 1).
2
6
3
+
Found, %: C 70.37; H 6.03. M 408. C H O . Cal-
culated, %: C 70.57; H 5.92. M 408.45.
2
4
24
6
Dimethyl (E)-2,3-bis(4-fluorobenzoyl)-2-butene-
,4-dioate (E-IId). mp 207–208°C. IR spectrum
1
–
1
1
Dimethyl (E)-2,3-dibenzoyl-2-butene-1,4-dioate
(KBr), ν, cm : 1684, 1728. H NMR spectrum
–
1
(
E-IIa). mp 161–162°C. IR spectrum (KBr), ν, cm :
(CDCl ), δ, ppm: 3.59 s (6H, 2OMe), 7.20 d.d (4H,
3
1
1
3
7
(
(
676, 1730. H NMR spectrum (CDCl ), δ, ppm:
H
, J = 8.9, 8.4 Hz), 8.00 d.d (4H, H , J = 8.9,
3
arom arom
1
3
.56 s (6H, 2OMe), 7.52 d.d (4H, H
, J = 8.0,
5.3 Hz). C NMR spectrum (CDCl ), δ , ppm: 53.45 q
arom
3
C
3
.4 Hz), 7.63 t.t (2H, Harom, J = 7.4, 1.0 Hz), 7.99 d.d
4H, Harom, J = 8.0, 1.0 Hz). C NMR spectrum
CDCl ), δ , ppm: 53.30 q ( MeO, J = 148.5 Hz),
(MeO, J = 148.8 Hz), 116.28 d.d.d (C , J = 165.7,
1
3
2
22.0, 3.4 Hz), 131.45 d.d.d (C , J = 163.2, 9.8, 7.1 Hz),
131.98 m (C , J = 5.0 Hz), 142.07 s (C=C), 162.69 q
1
3
C
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 40 No. 9 2004

OXIDATION OF AROMATIC COMPOUNDS: XII.
1283
4
+
(
1
C=O, ester, J = 3.8 Hz), 166.27 d.t.t (C , J = 256.9,
5.0 Hz). Mass spectrum, m/z (I , %): 476 (10) M ,
rel
+
0.5, 5.0 Hz), 189.32 t (C=O, ketone, J = 3.6 Hz).
Mass spectrum, m/z (I , %): 388 (5) M , 357 (2), [M –
OMe] , 123 (100) [FC H CO] , 95 (25), 75 (5). Found,
154 (10), 153 (100) [MeOFC H CO] , 125 (7)
[MeOFC H ] , 110 (4), 95 (6). Found, %: C 60.68;
H 4.73. M 476. C H F O . Calculated, %: C 60.50;
24 22 2 8
6
3
+
+
rel
6 3
+
+
+
6
4
+
%
: C 61.89; H 3.67. M 388. C H F O . Calculated,
H 4.65. M 476.43.
2
0
14
2
6
%
: C 61.86; H 3.63. M 388.32.
Dimethyl (E)-2,3-bis(3,4-dimethoxybenzoyl)-2-
butene-1,4-dioate (E-IIf). mp 197–198°C. IR spec-
Diethyl (E)-2,3-bis(4-methoxy-3-nitrobenzoyl)-2-
butene-1,4-dioate (E-IIi). mp 232–234°C. IR spec-
–
1
1
trum (CHCl ), ν, cm : 1670, 1720. H NMR spectrum
3
–
1
1
trum (CHCl ), ν, cm : 1670, 1715. H NMR spectrum
(CDCl ), δ, ppm: 1.02 t (6H, 2Me, J = 7.1 Hz), 4.06 s
3
3
(
2
8
CDCl ), δ, ppm: 3.56 s (6H, 2CO Me), 3.94 s (6H,
(6H, 2OMe), 4.08 q (4H, 2OCH , J = 7.1 Hz), 7.21 d
3
2
2
OMe), 3.96 s (6H, 2OMe), 6.90 d (2H, H , J =
(2H, Harom, J = 8.7 Hz), 8.13 d.d (2H, Harom, J = 8.7,
arom
.3 Hz), 7.50 d.d (2H, H , J = 8.3, 1.5 Hz), 7.60 d
2.1 Hz), 8.46 d (2H, H , J = 2.1 Hz). Mass spectrum,
arom
arom
13
+
+
(
2H, Harom, J = 1.5 Hz). C NMR spectrum (CDCl ),
m/z (I , %): 530 (6) M , 485 (2) [M –OEt] , 457 (2)
[M – CO Et] , 181 (10), 180 (100) [MeO(NO )-
C H CO] , 133 (6), 106 (9), 105 (18), 104 (17), 76 (8).
Found, %: C 54.31; H 4.19. M 530. C H N O .
3
rel
+
δ , ppm: 53.32 q (MeO, J = 148.5 Hz), 56.07 q (MeO,
C
2
2
+
J = 144.8 Hz), 56.21 q (MeO, J = 145.3 Hz), 109.74 d.d
6
3
2
5
+
(
C , J = 160.5, 7.2 Hz), 110.38 d (C , J = 160.5 Hz),
2
4
22
2
12
6
1
1
8
1
3
24.62 d.d (C , J = 161.4, 6.7 Hz), 128.90 d (C , J =
.1 Hz), 142.04 s (C=C), 149.60 m (C , J = 5.0 Hz),
54.28 m (C , J = 5.0 Hz), 163.20 q (C=O, ester, J =
.9 Hz), 189.53 t (C=O, ketone, J = 4.8 Hz). Mass
Calculated, %: C 54.34; H 4.18. M 530.44.
3
4
REFERENCES
+
spectrum, m/z (I , %): 472 (14) M , 413 (5) [M –
CO Me] , 236 (2) M , 165 (100) [(MeO) C H CO] ,
1. Vasil’ev, A.V., Fundamenskii, V.S., Savechenkov, P.Yu.,
and Rudenko, A.P., Russ. J. Org. Chem., 2003, vol. 39,
p. 860.
rel
+
2+
+
2
2
6
3
+
1
37 (7) [(MeO) C H ] , 122 (4), 107 (14), 94 (3), 79
2 6 3
+
(6). Found, %: C 59.84; H 5.17. M 472. C H O .
2. Rudenko, A.P. and Vasil’ev, A.V., Russ. J. Org. Chem.,
2
4
24 10
1
995, vol. 31, p. 1360.
. Vasil’ev, A.V. and Rudenko, A.P., Russ. J. Org. Chem.,
997, vol. 33, p. 1555.
4. Rudenko, A.P. and Vasil’ev, A.V., Russ. J. Org. Chem.,
000, vol. 36, p. 1548.
Calculated, %: C 61.01; H 5.12. M 472.45.
3
Diethyl (E)-2,3-bis(4-methoxybenzoyl)-2-butene-
,4-dioate (E-IIg). Oily substance. IR spectrum
1
1
–
1
1
(
(
(
(
CHCl ), ν, cm : 1675, 1720. H NMR spectrum
3
2
CDCl ), δ, ppm: 0.95 t (6H, 2Me, J = 7.1 Hz), 3.88 s
3
5
. Vasil’ev, A.V., Rudenko, A.P., and Grinenko, E.V., Russ.
J. Org. Chem., 2000, vol. 36, p. 1157.
6H, 2OMe), 4.02 q (4H, 2OCH , J = 7.1 Hz), 6.98 d
4H, Harom, J = 8.9 Hz), 7.96 d (4H, Harom, J = 8.9 Hz).
2
+
6. Vasil’ev, A.V., Rudenko, A.P., and Fundamenskii, V.S.,
Mass spectrum, m/z (I , %): 440 (5) M , 395 (1) [M –
OEt] , 367 (1) [M – CO Et] , 136 (9), 135 (100)
rel
+
+
Russ. J. Org. Chem., 2001, vol. 37, p. 523.
7. Graziano, M.L., Iesce, M.R., and Scarpati, R., J. Chem.
Soc., Perkin Trans. 1, 1982, p. 2007.
2
+
[
MeOC H CO] , 107 (4), 92 (5), 77 (9), 64 (2). Found,
6 4
+
%: C 65.49; H 5.55. M 440. C H O . Calculated, %:
24 24 8
8
. Graziano, M.L., Iesce, M.R., Carli, B., and Scarpati, R.,
Synthesis, 1983, p. 125.
C 65.45; H 5.49. M 440.45.
Diethyl (E)-2,3-bis(3-fluoro-4-methoxybenzoyl)-
-butene-1,4-dioate (E-IIh). mp 137–139°C. IR spec-
9
. Freudenberg, K. and Wilke, G., Chem. Ber., 1952,
vol. 85, p. 78.
2
–
1
1
trum (CHCl ), ν, cm : 1670, 1720. H NMR spectrum
3
1
0. Walker, G.N., J. Am. Chem. Soc., 1954, vol. 76, p. 309.
(
(
CDCl ), δ, ppm: 0.97 t (6H, 2Me, J = 7.0 Hz), 3.96 s
3
11. Barabanov, I.I., Fedenok, L.G., and Shvartsberg, M.S.,
6H, 2Me), 4.04 q (4H, J = 7.0 Hz), 7.03 d.d (2H,
Izv. Ross. Akad. Nauk, Ser. Khim., 1998, p. 2327.
Harom, J = 8.4, 7.9 Hz), 7.71 d (2H, Harom, J = 8.4 Hz),
1
2. Rudenko, A.P., Vasil’ev, A.V., Savechenkov, P.Yu.,
Sommer, Zh., Khauas, M., and Val’spurzhe, S., Inter-
mediaty. Sintez, protonirovanie i okislenie atsetileno-
vykh soedinenii (Intermediates. Synthesis, Protonation,
and Oxidation of Acetylenic Compounds), St. Peters-
burg: Lesotekhn. Akad., 2003, vol. 2, p. 76.
1
3
7.74 d (2H, Harom, J = 11.3 Hz). C NMR spectrum
(
1
CDCl ), δ , ppm: 56.32 q (MeO, J = 145.8 Hz),
3
C
3.42 t.q (OCH , J = 127.6, 2.5 Hz), 62.79 q.t (MeO,
2
5
J = 149.2, 4.2 Hz), 112.53 d (C , J = 161.9 Hz),
2
115.76 d.d.d (C , J = 164.0, 19.1, 7.6 Hz), 126.70 d.d.d
6
1
(
C , J = 162.3, 7.2, 3.0 Hz), 129.13 d.d (C , J =
13. Benghait, J. and Becker, A., J. Org. Chem., 1958,
vol. 23, p. 885.
14. Sakamoto, T., Shiga, F., Yasuhara, A., Uchiyama, D.,
Kondo, Y., and Yamanaka, H., Synthesis, 1992, p. 746.
3
7
7
.7 Hz), 141.75 s (C=C), 152.26 d.d.d.d (C , J = 249.1,
, 7, 1.5 Hz), 152.68 m (C , J = 5.0 Hz), 162.41 q
4
(
C=O, ester, J = 3.2 Hz), 188.72 t (C=O, ketone, J =
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 40 No. 9 2004