Oxidative coupling reaction of 1,3-diarylpropenes with propane-1,3-dione derivatives mediated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone with molecular oxygen

Article abstract of DOI:10.3184/174751914X14179672591720

An oxidative coupling reaction between 1,3-diarylpropenes and propane-1,3-dione derivatives mediated by a catalytic amount of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and azobisisobutyronitrile with molecular oxygen has been developed. The corresponding products are obtained in moderate to good yields.

Full text of DOI:10.3184/174751914X14179672591720

JOURNAL OF CHEMICAL RESEARCH 2014
VOL. 38 DECEMBER, 751–753
RESEARCH PAPER 751
Oxidative coupling reaction of 1,3-diarylpropenes with propane-1,3-dione
derivatives mediated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone with
molecular oxygen
Dongping Cheng, Kun Yuan, Xiayi Zhou and Jizhong Yan*
College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, P.R. China
An oxidative coupling reaction between 1,3-diarylpropenes and propane-1,3-dione derivatives mediated by a catalytic amount
of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and azobisisobutyronitrile with molecular oxygen has been developed. The
corresponding products are obtained in moderate to good yields.
Keywords: oxidative coupling, oxygen, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, azobisisobutyronitrile
The coupling reaction through direct oxidation of two C–H
or heteroatom–H bonds is one of the most efficient and
atom-economical methods for constructing new bonds.1,2
2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as an
efficient oxidant has been already applied for the coupling
reaction.1 Ourgrouphasstudiedaseriesofthecouplingreactions
between 1,3-diarylpropenes and compounds containing active
hydrogen.3–9 However, in these reactions, a stoichiometric or
excess amount of DDQ is usually required and the by-product
H2DDQ makes the purification difficult. Several inorganic
co-oxidants such as Mn(OAc)3,10–11 MnO212 and FeCl313 have
been used to regenerate DDQ and the amount of DDQ required
decreased to 0.1–0.2 equiv. But these co-oxidants are required
in a large excess which is an environmental problem.
between 1,3-diarylpropenes and active methylenic compounds
mediated by a catalytic amount of DDQ with AIBN as an
additive in the presence of O2.
Results and discussion
Tobeginourstudy, wechosethereactionof1,3-diphenylpropene
(1a) with dicarbonyl compound (2a) as a model reaction. It
was catalysed by 10 mol% DDQ and 10 mol% AIBN at 60 °C
in the atmosphere of oxygen (balloon). The desired coupled
product 3a was obtained in 47% yield after 6 h (Table 1,
entry 1). Performing the reaction under anaerobic conditions
or without AIBN resulted in low yield (Table 1, entries 2 and
3). No coupling product was obtained in the absence of DDQ
(Table 1, entry 4). This indicated that DDQ is essential, and that
molecular oxygen and AIBN could promote the reaction. Then
the temperature was raised to 80 °C and 100 °C, the coupling
product was obtained in 51% and 54% yields respectively
(Table 1, entries 5 and 6). It was shown that increasing the
temperature improved the reaction. Finally, the amounts of
DDQ and AIBN were examined (Table 1, entries 7–11). Yield
was decreased when the amount of the DDQ and AIBN was
reduced. The combination of DDQ (20 mol%) and AIBN
(20 mol%) gave the best result. Prolonging the reaction time to
24 h gave the expected product in 64% yield (Table 1, entry 12).
From the aspect of green chemistry,14 molecular oxygen is an
ideal co-oxidant because of its cheapness and water is the only
by-product. But there have been few reports of the oxidation
promoted by a catalytic amount of DDQ with molecular
oxygen as co-oxidant.15–21 For example, Prabhu has developed
the coupling reaction of N-aryltetrahydroisoquinoline using
catalytic amount of DDQ and azobisisobutyronitrile (AIBN)
with molecular oxygen.17 Our group has studied the alkylation
of 1,3-diarylpropene catalysed by DDQ/N-hydroxyphthalimide
at the atmosphere of O2.20 We now report the coupling reaction
Table 1 Optimisation of the reaction conditionsa
Table 2 Oxidative coupling reaction of 1,3-diarylpropenesa
O
O
O
O
DDQ (20 mol%)
AIBN (20 mol%)
O
O
O
O
DDQ/AIBN
O2(1atm)
Ph
Ph
Ph
R3
R4
Ph
Ph
R1
R2
Ph
R3
R4
CH3NO2
O2 (1 atm)
R1
R2
Ph
Ph
3
1a
2a
3a
1
2
Entry DDQ/mol% AIBN/mol% Temp./oC
Time/h
Yield/%b
Entry
R1, R2
R3, R4
Product (3) Yield/%b
1
2
3c
4
5
6
7
8
9
10
10
10
0
10
10
5
10
0
60
60
60
60
80
100
100
100
100
100
100
100
6
6
6
6
6
6
6
6
6
47
8
18
0
51
54
10
23
36
58
52
64
1
2
3
4
5
6
7
8
9
C6H5, C6H5
C6H5, C6H5
C6H5, C6H5
C6H5, C6H5
C6H5, C6H5
C6H5, C6H5
C6H5, C6H5
C6H5, C6H5
C6H5, C6H5
C6H5, C6H5
3a
3b
3c
3d
3e
3f
3g
3h
3i
64
65
81
79
51
49
62
56
61
70
84
58
C6H5, 4-CH3C6H4
C6H5, 4-CH3OC6H4
C6H5, 3-CH3OC6H4
C6H5, 4-FC6H4
C6H5, 4-BrC6H4
C6H5, CH3
10
10
10
10
5
15
100
20
40
20
5
10
20
20
20
CH3, CH3
CH3, OCH2CH3
10
11
12
6
6
24
10 C6H5, 4-CH3OC6H4 C6H5, C6H5
11 C6H5, 4-BrC6H4
12 4-CH3C6H4, C6H5
3j
3k
3l
C6H5, C6H5
C6H5, C6H5
a1a (0.24 mmol), 2a (0.2 mmol), CH3NO2 (1 mL), O2 balloon.
bIsolated yields.
a1 (0.24 mmol), 2 (0.2 mmol), DDQ (20 mol%), AIBN (20 mol%), CH3NO2
(1 mL), 100 °C, 24 h, O2 balloon.
cIn the absence of O2.
bIsolated yield.
* Correspondent. E-mail: yjz@zjut.edu.cn
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752 JOURNAL OF CHEMICAL RESEARCH 2014
(125 MHz, CDCl3): 194.7, 194.0, 192.7, 192.0, 163.8, 163.6, 141.14,
141.05, 137.4, 137.02, 137.0, 133.4, 133.1, 131.8, 131.7, 131.3, 131.0,
130.2, 130.13, 129.9, 128.8, 128.79, 128.61, 128.60, 128.56, 128.5,
128.35, 128.32, 128.30, 127.30, 127.28, 126.8, 126.28, 126.27, 114.1,
113.8, 62.78, 62.66, 55.5, 55.4, 49.96, 49.90.
2-[(2E)-1,3-Diphenylprop-2-en-1-yl]-1-(3-methoxylphenyl)-3-
phenylpropane-1,3-dione (3d): White solid; m.p. 100–102 °C (lit.3
99–101 °C). 1H NMR (500 MHz, CDCl3): δ 8.08–8.07 (m, 1H),
7.86–7.84 (m, 1H), 7.70 (d, J=7.7 Hz, 0.5×1H), 7.57 (t, J=7.4 Hz,
0.5×1H), 7.50–7.46 (m, 2+0.5×1H), 7.40–7.09 (m, 13), 7.04–7.02 (m,
0.5H),6.37–6.35 (m, 2H), 6.01, 5.99 (dd, J=10.5, 10.5 Hz, 1H), 4.83
(dd, J=7.2, 10.5 Hz, 1H), 3.74 (s, 0.5×3H), 3.73 (s, 0.5×3H). 13C NMR
(125 MHz, CDCl3): 194.4, 194.1, 193.7, 193.4, 160.0, 159.7, 141.0, 140.9,
138.6, 138.2, 137.2, 136.85, 136.82, 133.4, 133.2, 131.84, 131.78, 129.9,
129.5, 128.9, 128.7, 128.61, 128.58, 128.55, 128.46, 128.3, 128.26,
128.24, 128.23, 127.3, 126.8, 126.21, 126.19, 121.1, 120.9, 120.3, 120.1,
112.8, 112.5, 62.5, 62.4, 55.3, 55.2, 50.06, 50.04.
2-[(2E)-1,3-Diphenylprop-2-en-1-yl]-1-(4-flurophenyl)-3-phenyl-
propane-1,3-dione (3e): White solid; m.p. 119–121 °C. 1H NMR
(500 MHz, CDCl3): δ 8.12–8.05 (m, 2H), 7.90–7.83 (m, 2H), 7.58 (t,
J=7.4 Hz, 0.5×1H), 7.51–7.46 (m, 1+0.5×1H), 7.38–7.35 (m, 3H),
7.27–7.11 (m, 9H), 7.02 (t, J=8.6 Hz, 1H), 6.38–6.29 (m, 2H), 5.93, 5.92
(dd, J=10.7, 10.6 Hz, 1H), 4.82 (dd, J=7.2, 10.6 Hz, 1H). 13C NMR
(125 MHz, CDCl3): 194.3, 193.8, 192.8, 192.3, 166.9, 166.7, 164.9,
164.7, 140.8, 137.2, 136.8, 133.6, 133.4, 133.3, 132.0, 131.6, 131.5, 131.3,
131.2, 129.8, 129.7, 128.8, 128.7, 128.66, 128.4, 128.33, 128.30, 127.5,
127.4, 127.0, 126.3, 126.25, 116.1, 116.0, 115.8, 115.7, 63.1, 63.0, 50.0,
49.98. HRMS(ESI): calcd for C30H23FNaO2 [M+Na+] 457.1580; found
457.1581.
2-[(2E)-1,3-Diphenylprop-2-en-1-yl]-1-(4-bromophenyl)-3-phenyl-
propane-1,3-dione (3f): White solid; m.p. 189–195 °C. 1H NMR
(500 MHz, CDCl3): δ 8.05–8.03 (m, 0.8×2H), 7.91 (d, J=8.7 Hz,
0.2×2H), 7.83 (d, J=7.4 Hz, 0.2×2H), 7.71–7.68 (m, 0.8×2H),
7.60–7.57 (m, 1H), 7.50–7.46 (m, 3H), 7.38–7.10 (m, 11H), 6.38–6.28
(m, 2H), 5.91, 5.90 (dd, J=10.7, 10.5 Hz, 1H), 4.81 (dd, J=7.7, 10.6 Hz,
1H). 13C NMR (125 MHz, CDCl3): 194.1, 193.6, 193.5, 192.9, 140.7,
137.1, 136.8, 136.75, 135.9, 135.6, 133.6, 133.4, 132.2, 132.0, 131.9,
130.3, 130.0, 129.7, 129.6, 129.0, 128.8, 128.7, 128.69, 128.6, 128.5,
128.4, 128.3, 128.28, 127.5, 127.4, 127.01, 127.0, 126.3, 62.9, 50.0.
HRMS(ESI): calcd for C30H27BrNO2 [M+NH4+] 512.1225; found
512.1233.
With the optimised reaction conditions established, various
dicarbonyl compounds were subjected to the oxidative
coupling reaction (Table 2). It was observed that the reaction
was sensitive to electronic changes on the benzene ring of the
dicarbonyl compounds (Table 2, entries 2–6). The substrates
with electron donating-group on the benzene ring reacted well
under the standard reaction condition and 69–86% yields were
obtained, while the substrates with electron withdrawing-
group were used and the yields decreased. Acetylacetone,
benzoylacetone and β‑keto ester were also compatible with the
present procedure and moderate yields were given (Table 2,
entries 7–9). To expand the scope of the substrates, other
1,3-diarylpropenes were further examined. The expected
products were obtained in satisfactory yields (Table 2,
entries 10–12).
In summary, we have developed an oxidative coupling
reaction between 1,3-diarylpropenes and active methylenic
compounds mediated by a catalytic amounts of DDQ and
AIBN with molecular oxygen as an co-oxidant.
Experimental
Column chromatography was carried out on silica gel
(200–300 mesh). 1H NMR spectra was recorded on Bruker AMX-
500 MHz instrument and the chemical shifts were reported in parts
per million (δ) relative to internal standard TMS (0 ppm) for CDCl3.
The coupling constants, J, are reported in Hz. Low-resolution mass
spectra were obtained using EI or ESI ionisation. IR spectra were
determined on a Nicolet 6700 spectrometer. Elemental analysis was
determined by Carbo Erbo EA-1110. Melting points were uncorrected.
All reagents were weighed and handled in air at room temperature and
all reactions were performed without exclusion of air or moisture.
Oxidative coupling reaction of 1,3-diarylpropenes 3; general
procedure
DDQ (9.08 mg, 0.04 mmol) and AIBN (0.04 mmol) were added to a
mixture of 1,3-diarylpropene (0.24 mmol) and substrate 2 (0.2 mmol)
in CH3NO2 (1 mL). It was carried out at 100 °C under oxygen
atmosphere (oxygen balloon) for 24 h. The resulting mixture was
purified by flash column chromatography on silica gel (petroleum
ether–ethyl acetate=10:1–20:1) to give the desired pure product 3.
2-[(2E)-1,3-diphenylprop-2-en-1-yl]-1,3-diphenylpropane-1,3-
1
dione (3a): White solid; m.p. 125–127°C (lit.3 123–125°C). H NMR
2-[(2E)-1,3-Diphenylprop-2-en-1-yl]-1-phenylbutane-1,3-dione (3g):
1
White solid; m.p. 130–132 °C (lit.3 130–132 °C). H NMR (500 MHz,
(500 MHz, CDCl3): δ 8.07–8.05 (m, 2H), 7.85–7.83 (m, 2H), 7.58–7.55
(m, 1H), 7.49–7.45 (m, 3H), 7.38–7.35 (m, 4H), 7.26–7.09 (m, 8H),
6.38–6.29 (m, 2H), 5.99 (d, J=10.6 Hz, 1H), 4.82 (dd, J=7.0, 10.6 Hz,
1H). 13C NMR (125 MHz, CDCl3): 194.4, 193.8, 141.0, 140.9, 137.3,
136.9, 133.4, 133.2, 131.9, 129.9, 128.9, 128.8, 128.63, 128.58, 128.52,
128.32, 128.30, 127.3, 126.9, 126.3, 62.7, 50.0.
2-[(2E)-1,3-Diphenylprop-2-en-1-yl]-1-(4-methylphenyl)-3-
phenyl-propane-1,3-dione (3b): White solid; m.p. 123–124°C (lit.20
120–122 °C). 1H NMR (500 MHz, CDCl3): δ 8.07 (d, J=7.5 Hz,
0.7 ×2H), 7.98 (d, J=8.2 Hz, 0.3×2H), 7.85 (d, J=7.4 Hz, 0.3×2H),
7.78 (d, J=8.3 Hz, 0.7×2H), 7.56 (t, J=7.4 Hz, 0.3×2H), 7.46 (t,
J=7.6 Hz, 0.7×2H), 7.39–7.11 (m, 13H), 6.36–6.34 (m, 2H), 5.99
(d, J=10.5 Hz, 1H), 4.85–4.82 (m, 1H), 2.40 (s, 0.3×3H), 2.34 (s,
0.7 ×3H). 13C NMR (125 MHz, CDCl3): 194.5, 193.9, 193.8, 193.2,
144.5, 144.2, 141.03, 141.01, 137.3, 136.94, 136.91, 134.8, 134.3, 133.4,
133.1, 131.8, 131.7, 130.1, 130.0, 129.6, 129.3, 129.0, 128.83, 128.76,
128.70, 128.6, 128.5, 128.49, 128.3, 128.29, 128.28, 128.26, 127.28,
127.26, 126.8, 126.25, 126.23, 62.5, 50.0, 49.9, 21.62, 21.56.
CDCl3): δ 8.10–8.08 (m, 1H), 7.91–7.89 (m, 1H), 7.61 (t, J=7.4 Hz,
0.5×1H), 7.55–7.49 (m, 1+0.5×1H), 7.43–7.11 (m, 11H), 6.57 (d,
J=15.8 Hz, 0.5×1H), 6.40–6.35 (m, 0.5×1+0.5×1H), 6.17 (dd, J=7.8,
15.8 Hz, 0.5×1H), 5.25, 5.21 (dd, J=11.3, 11.3 Hz, 1H), 4.69–4.61 (m,
1H), 2.27 (s, 0.5×3H), 2.01 (s, 0.5×3H). 13C NMR (125 MHz, CDCl3):
203.0, 202.5, 194.5, 194.3, 140.7, 140.0, 137.2, 136.9, 136.8, 136.7,
133.8, 133.7, 131.7, 131.65, 130.0, 129.4, 129.0, 128.9, 128.89, 128.82,
128.75, 128.73, 128.6, 128.56, 128.38, 128.35, 128.3, 127.9, 127.7, 127.5,
127.4, 126.9, 126.5, 126.3, 69.5, 68.7, 49.5, 49.3, 28.1, 27.8.
3-[(2E)-1,3-Diphenylprop-2-en-1-yl]-pentane-2,4-dione (3h): White
1
solid; m.p. 82–84 °C (lit.3 81–83 °C). H NMR (500 MHz, CDCl3):
δ 7.33–7.18 (m, 10H), 6.43 (d, J=15.8 Hz, 1H), 6.22–6.17 (m, 1H),
4.36–4.31 (m, 2H), 2.25 (s, 3H), 1.92 (s, 3H). 13C NMR (125 MHz,
CDCl3): 202.8, 202.6, 140.0, 136.5, 131.6, 129.2, 129.0, 128.5, 127.9,
127.7, 127.2, 126.3, 74.4, 49.1, 30.0, 29.7.
Ethyl 2-acetyl-3,5-diphenylpent-4-enoate (3i):3 Pale yellow oil.
1H NMR (500 MHz, CDCl3): δ 7.36–7.21 (m, 10H), 6.55, 6.46
(dd, J=15.8, 15.9 Hz, 1H), 6.35–6.25 (m, 1H), 4.34–4.30 (m, 1H),
4.21–4.11 (m, 2H), 3.98–3.94 (m, 1H), 2.33 (s, 0.5×3H), 2.06 (s,
0.5×3H), 1.24 (t, J=7.1 Hz, 0.5×3H), 1.00 (t, J=7.2 Hz, 0.5×3H).
13C NMR (125 MHz, CDCl3): 201.6, 201.4, 167.9, 167.5, 140.3, 140.2,
136.8, 136.6, 131.8, 131.5, 129.5, 129.3, 128.9, 128.8, 128.6, 128.5,
128.0, 127.9, 127.6, 127.5, 127.1, 127.0, 126.3, 126.29, 65.5, 65.2, 61.6,
61.3, 48.9, 48.7, 30.3, 29.8, 14.1, 13.7.
2-[(2E)-1,3-Diphenylprop-2-en-1-yl]-1-(4-methoxylphenyl)-3-
phenylpropane-1,3-dioe (3c): White solid; m.p. 171–173 °C (lit.3
172–174 °C). 1H NMR (500 MHz, CDCl3): δ 8.09–8.05 (m, 2H),
7.88–7.84 (m, 2H), 7.57–7.54 (m, 0.4×1H), 7.48–7.44 (m, 1+0.6×1H),
7.38–7.33 (m, 3H), 7.28–7.11 (m, 8H), 6.93 (d, J=8.9 Hz, 0.4×2H),
6.82 (d, J=8.9 Hz, 0.6×2H), 6.35–6.34 (m, 2H), 5.92 (d, J=10.7 Hz,
1H), 4.85–4.82 (m, 1H), 3.86 (s, 0.4×3H), 3.81 (s, 0.6×3H). 13C NMR
JCR1402911_FINAL.indd 752
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JOURNAL OF CHEMICAL RESEARCH 2014 753
2-[(2E)-1-(4-Methoxylphenyl)-3-phenyl-2-propenyl]-1,3-diphenyl-
1,3-propanedione (3j): White solid; m.p. 106–108 °C. 1H NMR
(500 MHz, CDCl3): δ 8.06 (d, J=3.1 Hz, 2H), 7.86–7.85 (m, 2H),
7.58–7.55 (m, 1H), 7.49–7.45 (m, 3H), 7.38–7.33 (m, 3H), 7.30–7.03
(m, 6H), 6.78 (d, J=8.7 Hz, 0.6×2H), 6.73 (d, J=8.7 Hz, 0.4×2H),
6.34–6.29 (m, 1+0.6H), 6.18 (dd, J=8.4, 15.7 Hz, 0.4×1H), 6.00,
5.96 (dd, J=10.6, 10.6 Hz, 1H), 4.83–4.79 (m, 1H), 3.76 (s, 0.4×3H),
3.73 (s, 0.6×3H). 13C NMR (125 MHz, CDCl3): 194.51, 194.45, 193.9,
193.8, 159.0, 158.4, 133.4, 133.2, 131.5, 131.3, 130.2, 129.3, 128.9,
128.8, 128.6, 128.53, 128.49, 128.3, 127.7, 127.4, 127.3, 126.2, 114.1,
114.0, 113.7, 62.9, 62.8, 55.19, 55.17, 50.0, 49.2. HRMS(ESI): calcd for
C31H26NaO3 [M+Na+] 469.1780; found 469.1781.
2-[(2E)-1-(4-bromophenyl)-3-phenylprop-2-en-1-yl]-1,3-diphenyl-
propane-1,3-dione (3k): White solid; m.p. 121–123 °C. 1H NMR
(500 MHz, CDCl3): δ 8.07–8.06 (m, 2H), 7.87–7.84 (m, 2H), 7.57
(t, J=7.4 Hz, 1H), 7.52–7.45 (m, 3H), 7.38–7.09 (m, 10H), 6.95 (d,
J=8.5 Hz, 1H), 6.36–6.25 (m, 2H), 6.00, 5.97 (dd, J=10.5, 10.6 Hz,
1H), 4.83–4.78 (m, 1H). 13C NMR (125 MHz, CDCl3): 194.4, 194.2,
193.6, 193.55, 140.7, 140.1, 137.2, 137.1, 136.8, 136.7, 136.65, 135.8,
133.6, 133.56, 133.5, 133.3, 132.3, 131.7, 131.4, 130.8, 130.7, 130.1,
129.2, 129.0, 128.8, 128.77, 128.7, 128.6, 128.54, 128.51, 128.4,
128.3, 127.8, 127.5, 127.0, 126.3, 121.1, 120.7, 62.6, 62.5, 50.0, 49.4.
HRMS(ESI): calcd for C30H23BrNaO2 [M+Na+] 517.0779; found
517.0778.
2-[(2E)-1-Phenyl-3-(4-methylphenyl)prop-2-en-1-yl]-1,3-diphenyl-
propane-1,3-dione (3l): White solid; m.p. 132–134 °C. 1H NMR
(500 MHz, CDCl3): δ 8.07–8.01 (m, 2H), 7.87–7.84 (m, 2H), 7.58–7.45
(m, 4H), 7.38–7.33 (m, 3H), 7.28–7.00 (m, 8H), 6.33–6.28 (m, 2H),
6.01–5.97 (m, 1H), 4.84–4.78 (m, 1H), 2.28 (s, 0.5×3H), 2.26 (s,
0.5×3H). 13C NMR (125 MHz, CDCl3): 194.5, 194.4, 193.8, 141.1,
137.9, 137.3, 137.1, 137.0, 136.9, 136.4, 134.1, 133.4, 133.2, 132.5, 131.7,
131.6, 130.1, 129.3, 129.0, 128.9, 128.84, 128.80, 128.7, 128.6, 128.57,
128.5, 128.3, 128.26, 128.1, 127.3, 127.2, 126.8, 126.2, 126.1, 62.8, 62.7,
50.0, 49.6, 21.1, 21.0. HRMS(ESI): calcd for C31H30NO2 [M+NH4+]
448.2277; found 448.2271.
This work was supported by the Research Fund of Zhejiang
University of Technology (1001116044408).
Received 24 September 2014; accepted 18 November 2014
Paper 1402911 doi: 10.3184/174751914X14179672591720
Published online: 19 December 2014
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