Three-component reaction of triphenylphosphine, dimethyl acetylenedicarboxylate, and aldehyde benzoylhydrazones: An efficient one-pot synthesis of stable phosphorus ylides

Article abstract of DOI:10.1080/00397910802369703

Protonation of the reactive 1:1 intermediate produced in the reaction between dimethyl acetylenedicarboxylate and triphenylphosphine by benzoylhydrazones leads to vinylphosphonium salts, which undergo Michael addition with the conjugate base of the NH aci

Full text of DOI:10.1080/00397910802369703

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Three-Component Reaction of
Triphenylphosphine, Dimethyl
Acetylenedicarboxylate, and
Aldehyde Benzoylhydrazones:
An Efficient One-Pot Synthesis
of Stable Phosphorus Ylides
Alireza Hassanabadi a , Mohammad Anary-
Abbasinejad a & Alimohammad Dehghan a
a Department of Chemistry , Islamic Azad University,
Yazd Branch , Yazd, Iran
Published online: 15 Feb 2011.
To cite this article: Alireza Hassanabadi , Mohammad Anary-Abbasinejad &
Alimohammad Dehghan (2008) Three-Component Reaction of Triphenylphosphine,
Dimethyl Acetylenedicarboxylate, and Aldehyde Benzoylhydrazones: An Efficient One-
Pot Synthesis of Stable Phosphorus Ylides, Synthetic Communications: An International
Journal for Rapid Communication of Synthetic Organic Chemistry, 39:1, 132-138, DOI:
10.1080/00397910802369703
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Synthetic Communications1, 39: 132–138, 2009
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397910802369703
Three-Component Reaction of Triphenylphosphine,
Dimethyl Acetylenedicarboxylate, and Aldehyde
Benzoylhydrazones: An Efficient One-Pot
Synthesis of Stable Phosphorus Ylides
Alireza Hassanabadi, Mohammad Anary-Abbasinejad, and
Alimohammad Dehghan
Department of Chemistry, Islamic Azad University,
Yazd Branch, Yazd, Iran
Abstract: Protonation of the reactive 1:1 intermediate produced in the reaction
between dimethyl acetylenedicarboxylate and triphenylphosphine by benzoylhy-
drazones leads to vinylphosphonium salts, which undergo Michael addition with
the conjugate base of the NH acid to produce highly fanctionalized, salt-free
phosphorus ylides in excellent yields.
Keywords: Benzoylhydrazones, dimethyl acetylenedicarboxylate, NH acids,
phosphorus ylides, triphenylphosphine
Phosphorus ylides are reactive systems, which take part in many reactions of
value in organic synthesis.[1–7] Several methods have been developed for the
preparation of phosphorus ylides. These ylides are usually prepared by treat-
ment of an appropriate phosphonium salt with a base; the corresponding
phosphonium salts are usually obtained from the phosphine and an alkyl
halide.[1,2] Phosphonium salts are also prepared by Michael addition of
phosphorus nucleophiles to activated olefins.[1] Reaction of acetylenic esters
with triphenylphosphine in the presence of an organic compound containing
an acidic hydrogen has also been reported to produce phosphorus ylides.[8]
Received June 13, 2008.
Address correspondence to Mohammad Anary-Abbasinejad, Department of
Chemistry, Islamic Azad University, Yazd Branch, P.O. Box 89195-155, Yazd,
Iran. E-mail: mohammadanary@yahoo.com
132

One-Pot Synthesis of Phosphoranes
133
In continuation of our work on the reaction between trivalent phosphorus
nucleophiles and electron-deficient acetylenic compounds in the presence
of organic N-H, O-H, or C-H acids,[9–19] we herein report an efficient syn-
thetic route to stable phosphorus ylides using triphenylphosphine, dimethyl
acetylenedicarboxylate, and benzoylhydrazones. Thus, the reaction of the
benzoylhydrazones 1 with dimethyl acetylenedicarboxylate 2 in the presence
of triphenylphosphine 3 leads to the corresponding ylides 4 in good yields
(Scheme 1).
1
The H NMR spectrum of compound 4a displays two sharp lines
(d 2.82, 3.60 ppm) for the methyl groups, a doubled signal for the methine
proton at 5.72 (3JHP ¼ 16 HZ), a single signal at 8.35 ppm for the CH ¼ N
proton, and multiplets between 7.06 and 7.32 ppm for aromatic protons.
The 31P NMR spectrum of compound 4a consists of one signal at 23.2.
This shift is similar to those observed for other stable phosphorus
ylides.[20,21] The structural assignments made on the basis of the NMR
spectra of compounds 4a–f are supported by their IR spectra. The carbo-
nyl region of the spectrum exhibits absorption bands at 1650–1747 cmꢀ1
for the ester groups.
It is reasonable to assume that ylide 4 results from the initial addition
of triphenylphosphine to dimethyl acetylene dicarboxylate (DMAD) and
subsequent protonation of the 1:1 adduct by the NH-acidic benzoyl-
hydrazone. The positively charged 5 is then attacked by the benzoyl-
hydrazone anion 6 to form the phosphorane 4 (Scheme 2).
In summary, we report hearin that three-component reaction of triphe-
nylphosphine, dimethyl acetylenedicarboxylate, and benzoylhydrazones
Scheme 1. Three-component reaction of triphenylphosphine, dimethyl acetylene-
dicarboxylate, and benzoylhydrazones.

134
A. Hassanabadi, M. Anary-Abbasinejad, and A. Dehghan
Scheme 2. Mechanism of formation of ylide 4.
produces functionalized phosphoranes in good yields. The reaction is carried
out under neutral conditions, and starting materials are used without any
need for purification or modification.
EXPERIMENTAL
All melting points are uncorrected. Elemental analyses were performed
using a Heraeus CHN-O-Rapid analyzer. Mass spectra were recorded
on a Finnigan-MAT 8430 mass spectrometer operating at an ionization
potential of 70 eV. IR spectra were recorded on a Shimadzu IR-470
1
spectrometer. H, 13C, and 31P NMR spectra were recorded on Bruker
DRX-500 Avance spectrometer at 500, 128.5, and 202.5 MHz, respec-
tively. 1H, 13C, and 31P NMR spectra were obtained on solution in
dimethyl sulfoxide (DMSO) using tetramethylsilane (TMS) as internal
standard or 85% H3PO4 as external standard. The chemicals used in this
work purchased from Fluka (Buchs, Switzerland) and were used without
further purification.
General Procedure
A mixture of dimethyl acetylenedicarboxylate (0.28 g, 2 mmol) in acetonitrile
(3 ml) was added dropwise to a magnetically stirred solution of triphenyl-
phosphine (0.52 g, 2 mmol) and benzaldehyde benzoylhydrazone (0.45 g,
2mmol) in acetonitrile (15 ml) at room temperature over 2min. The reaction
mixture was then stirred for 2 h. The solvent was evaporated at reduced pres-
sure. The residue was precipitated in a mixture of diethyl ether–hexane. The
solid was filtered and washed with diethyl ether to give the pure product.
Dimethyl 3-(Triphenyl-k5-phosphanylidene)-2-(N-benzoyl-N-benzylidene-
hydrazino) Succinat (4a)
Yellow powder; mp 192–194ꢁC. IR (KBr) (nmax, cmꢀ1): 1747, 1695, 1650
(C ¼ O). Calcd. for C38H33N2O5P: C, 72.60; H, 5.29; N, 4.46%. Found: C,

One-Pot Synthesis of Phosphoranes
135
1
72.8; H, 5.4; N, 4.7%. MS (m=z, %): 628 (Mþ, 7). H NMR (500 MHz,
d6-DMSO): d 2.82 (3 H, s, OCH3), 3.60 (3 H, s, OCH3), 5.72 (1 H, d,
3JPH ¼ 16 Hz), 7.06–7.32 (25 H, m, aromatic), 8.35 (1H, s, CH ¼ N).
1
13C NMR (125.8 MHz, d6-DMSO): d 49.4 (d, JPC ¼ 122 Hz, C ¼ P),
2
1
52.8, 53.2 (2 OCH3), 59.7 (d, JPC ¼ 15 Hz, CH), 126.2 (d, JPC ¼ 91
Hz), 128.9 (2JPC ¼ 12 Hz), 132.4 (d, JPC ¼ 2 Hz), 133.7 (d, JPC ¼ 10
Hz), 127.2, 127.7, 128.8, 129.8, 129.9, 130.1, 135.8, 136.2 (2 ph), 152.6
(C ¼ N), 161.3 (C ¼ O), 168.6 (d, 2JPC ¼ 12 HZ C ¼ O), 172.2 (d, 3JPC ¼ 17
17 HZ C ¼ O). 31P NMR (202.5 MHz, d6-DMSO): d 23.19.
4
3
Dimethyl 3-(Triphenyl-k5-phosphanylidene)-2-[N-benzoyl-N-(2-methoxy-
benzylidene)-hydrazino] Succinat (4b)
Yellow powder; mp 140–142ꢁC. IR (KBr) (nmax, cmꢀ1): 1747, 1699, 1639
(C ¼ O). Calcd. for C39H35N2O6P: C, 71.11; H, 5.36; N, 4.25%. Found:
C, 71.4; H, 5.2; N, 4.4%. MS (m=z, %): 658 (Mþ, 9). 1H NMR
(500 MHz, d6-DMSO): d 3.14 (3 H, s, OCH3), 3.84 (3 H, s, OCH3),
3.87 (3 H, s, OCH3), 5.98 (1 H, d, 3JPH ¼ 16 HZ), 6.91–8.14 (24 H, m, aro-
matic), 8.72 (1H, s, CH ¼ N). 13C NMR (125.8 MHz, d6-DMSO): d 49.2
1
2
(d, JPC ¼ 122 Hz, C ¼ P), 52.5, 55.7, 55.8 (3 OCH3), 59.9 (d, JPC ¼ 15
Hz, CH), 126.9 (d, 1JPC ¼ 91 Hz), 129.7 (2JPC ¼ 12 Hz), 132.2 (d, 4JPC ¼ 2
3
2 Hz), 133.7 (d, JPC ¼ 10 Hz), 120.8, 122.8, 128.0, 128.4, 128.7, 128.8,
128.9, 131.6, 131.7, 144.5 (2 ph), 158.2 (C ¼ N), 164.2 (C ¼ O), 168.6
2
3
(d, JPC ¼ 12 HZ C ¼ O), 170.3 (d, JPC ¼ 17 HZ C ¼ O). 31P NMR
(202.5 MHz, d6-DMSO): d 23.37.
Dimethyl 3-(Triphenyl-k5-phosphanylidene)-2-[N-benzoyl-n-(4-methoxy-
benzylidene)-hydrazino] Succinat (4c)
Yellow powder; mp 198–200ꢁC. IR (KBr) (nmax, cmꢀ1): 1743, 1684, 1638
(C ¼ O). Calcd. for C39H35N2O6P: C, 71.11; H, 5.36; N, 4.25%. Found:
C, 71.4; H, 5.2; N, 4.4%. MS (m=z, %): 658 (Mþ, 7). 1H NMR
(500 MHz, d6-DMSO): d 3.09 (3 H, s, OCH3), 3.88 (3 H, s, OCH3),
3.91 (3 H, s, OCH3), 5.03 (1 H, d, 3JPH ¼ 16 Hz), 6.95–7.64 (24 H, m, aro-
matic), 8.62 (1H, s, CH ¼ N). 13C NMR (125.8 MHz, d6-DMSO): d 49.6
1
2
(d, JPC ¼ 122 Hz, C ¼ P), 52.8, 53.1, 55.8 (3 OCH3), 60.0 (d, JPC ¼ 15
Hz, CH), 126.6 (d, JPC ¼ 91 Hz), 129.7 (2JPC ¼ 12 Hz), 132.5
1
4
3
(d, JPC ¼ 2 Hz), 133.9 (d, JPC ¼ 10 Hz), 114.4, 126.9, 127.3, 129.1,
129.2, 130.4, 134.1, 136.6 (2 ph) 153.7 (C ¼ N), 161.3 (C ¼ O), 169.6
2
3
(d, JPC ¼ 12 Hz C ¼ O), 172.6 (d, JPC ¼ 17 Hz C ¼ O). 31P NMR
(202.5 MHz, d6-DMSO): d 23.34.

136
A. Hassanabadi, M. Anary-Abbasinejad, and A. Dehghan
Dimethyl 3-(Triphenyl-k5-phosphanylidene)-2-[N-benzoyl-n-(2-chloro-
benzylidene)-hydrazino] Succinat (4d)
Yellow powder; mp 195–197ꢁC. IR (KBr) (nmax, cmꢀ1): 1749, 1693, 1649
(C ¼ O). Calcd. for C38H32ClN2O5P: C, 68.83; H, 4.86; N, 4.22%. Found:
C, 68.7; H, 5.1; N, 4.5%. MS (m=z, %): 662 (Mþ, 4). 1H NMR (500MHz,
d6-DMSO): d 2.87 (3 H, s, OCH3), 3.60 (3 H, s, OCH3), 5.72 (1 H, d,
3JPH ¼ 16 Hz), 6.91–7.51 (24 H, m, aromatic), 8.52 (1H, s, CH ¼ N). 13C
1
NMR (125.8 MHz, d6-DMSO): d 49.5 (d, JPC ¼ 122 Hz, C ¼ P), 51.1,
2
1
52.6 (2 OCH3), 59.7 (d, JPC ¼ 15 Hz, CH), 126.9 (d, JPC ¼ 91 Hz), 129.7
(2JPC ¼ 12 Hz), 132.2 (d, JPC ¼ 2 Hz), 133.7 (d, JPC ¼ 10 Hz), 120.8,
4
3
122.8, 128.0, 128.4, 128.7, 128.8, 128.9, 131.6, 131.7, 144.5 (2 ph), 152.6
2
3
(C ¼ N), 161.9 (C ¼ O), 169.6 (d, JPC ¼ 12 Hz C ¼ O), 171.7 (d, JPC ¼ 17
Hz C ¼ O). 31P NMR (202.5 MHz, d6-DMSO): d 23.11.
Dimethyl 3-(Triphenyl-k5-phosphanylidene)-2-[N-benzoyl-n-(4-chloro-
benzylidene)-hydrazino] Succinat (4e)
Yellow powder; mp 188–190ꢁC. IR (KBr) (nmax, cmꢀ1): 1742, 1659, 1633
(C ¼ O). Calcd. for C38H32ClN2O5P: C, 68.83; H, 4.86; N, 4.22%. Found:
C, 68.7; H, 5.1; N, 4.5%. MS (m=z, %): 662 (Mþ, 6). 1H NMR (500 MHz,
d6-DMSO): d 3.07 (3 H, s, OCH3), 3.86 (3 H, s, OCH3), 6.06 (1 H, d,
3JPH ¼ 16 Hz), 7.35–7.67 (24 H, m, aromatic), 8.61 (1H, s, CH ¼ N).
1
13C NMR (125.8 MHz, d6-DMSO): d 49.3 (d, JPC ¼ 122 Hz, C ¼ P),
2
1
52.3, 52.8 (2 OCH3), 59.3 (d, JPC ¼ 15 Hz, CH), 126.9 (d, JPC ¼ 91
Hz), 129.6 (2JPC ¼ 12 Hz), 132.2 (d, JPC ¼ 2 Hz), 133.6 (d, JPC ¼ 10
4
3
Hz), 125.4, 128.4, 128.6, 128.9, 129.9, 132.0, 133.4, 135.9 (2 ph), 151.1
2
(C ¼ N), 163.8 (C ¼ O), 169.3 (d, JPC ¼ 12 Hz C ¼ O), 171.8
(d, JPC ¼ 17 Hz C ¼ O) .31P NMR (202.5 MHz, d6-DMSO): d 23.14.
3
Dimethyl 3-(Triphenyl-k5-phosphanylidene)-2-[N-benzoyl-n-(4-nitro-
benzylidene)-hydrazino] Succinat (4f)
Yellow powder; mp 182–184ꢁC. IR (KBr) (nmax, cmꢀ1): 1742, 1672, 1629
(C ¼ O). Calcd. for C38H32N3O7P: C, 67.75; H, 4.79; N, 6.24%. Found:
C, 67.9; H, 4.6; N, 6.5%. MS (m=z, %): 673 (Mþ, 6). 1H NMR
(500 MHz, d6-DMSO): d 2.99 (3 H, s, OCH3), 3.76 (3 H, s, OCH3),
3
5.87 (1 H, d, JPH ¼ 16 Hz), 7.34–7.68 (24 H, m, aromatic), 8.59 (1H, s,
1
CH ¼ N). 13C NMR (125.8 MHz, d6-DMSO): d 50.0 (d, JPC ¼ 122 Hz,
2
C ¼ P), 52.8, 53.4 (2 OCH3), 59.7 (d, JPC ¼ 15 Hz, CH), 125.9
1
4
(d, JPC ¼ 91 Hz), 130.0 (2JPC ¼ 12 Hz), 132.3 (d, JPC ¼ 2 Hz), 133.9

One-Pot Synthesis of Phosphoranes
137
(d, 3JPC ¼ 10 Hz), 125.3, 128.2, 128.3, 128.9, 130.2, 133.5, 135.9, 142.1 (2
2
ph), 148.7 (C ¼ N), 162.9 (C ¼ O), 169.5 (d, JPC ¼ 12 Hz C ¼ O), 171.9
3
(d, JPC ¼ 17 Hz C ¼ O). 31P NMR (202.5 MHz, d6-DMSO): d 23.11.
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