Synthesis of functionalized phosphonates and chromenes via catalyst-free multicomponent reactions in water

Article abstract of DOI:10.1080/10426507.2012.723768

Stable derivatives of phosphonates were prepared using multicomponent reactions of dialkyl acetylenedicarboxylate with 4-hydroxycumarin in the presence of trimethyl or triphenyl phosphite in good yields. Chromene derivatives were produced by using triethy

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Phosphorus, Sulfur, and Silicon and the
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Synthesis of Functionalized
Phosphonates and Chromenes via
Catalyst-Free Multicomponent Reactions
in Water
Zinatossadat Hossaini a , Faramarz Rostami Charati b & Mahboubeh
Ghasemian c
a Department of Chemistry, Qaemshahr Branch , Islamic Azad
University , Qaemshahr , Iran
b Department of Chemistry, Faculty of Science , Gonbad Kavous
University , Gonbad , Iran
c Department of Chemistry, North of Tehran Branch , Islamic Azad
University , Tehran , Iran
Accepted author version posted online: 30 Aug 2012.Published
online: 31 May 2013.
To cite this article: Zinatossadat Hossaini , Faramarz Rostami Charati & Mahboubeh Ghasemian
(2013): Synthesis of Functionalized Phosphonates and Chromenes via Catalyst-Free Multicomponent
Reactions in Water, Phosphorus, Sulfur, and Silicon and the Related Elements, 188:5, 555-560
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Phosphorus, Sulfur, and Silicon, 188:555–560, 2013
Copyright ꢀC Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426507.2012.723768
SYNTHESIS OF FUNCTIONALIZED PHOSPHONATES AND
CHROMENES VIA CATALYST-FREE MULTICOMPONENT
REACTIONS IN WATER
Zinatossadat Hossaini,1 Faramarz Rostami Charati,2
and Mahboubeh Ghasemian3
1Department of Chemistry, Qaemshahr Branch, Islamic Azad University,
Qaemshahr, Iran
2Department of Chemistry, Faculty of Science, Gonbad Kavous University,
Gonbad, Iran
3Department of Chemistry, North of Tehran Branch, Islamic Azad University,
Tehran, Iran
GRAPHICAL ABSTRACT
ABSTRACT Stable derivatives of phosphonates were prepared using multicomponent reac-
tions of dialkyl acetylenedicarboxylate with 4-hydroxycumarin in the presence of trimethyl
or triphenyl phosphite in good yields. Chromene derivatives were produced by using triethyl
phosphite and dialkyl acetylenedicarboxylate in the presence of 4-hydroxycumarin in excellent
yields.
Keywords Triphenyl phosphite; dialkyl acetylenedicarboxilates; multicomponent reactions;
triethyl phosphite
INTRODUCTION
Multicomponent reactions (MCRs), with three or more reactants combined in a
one-pot procedure to give a single product, have become increasingly popular during the
last decade.1–7 They are economically and environmentally advantageous because multi-
step syntheses produce considerable amounts of waste mainly due to complex isolation
procedures often involving expensive, toxic, and hazardous solvents after each step. The
developments of MCRs have attracted much attention from the vantage point of combinato-
rial and medicinal chemistry.8 Generally, the MCR strategy affords savings in synthetic time
and effort, and has significant advantages over conventional two-component reactions in
Received 16 June 2012; accepted 17 August 2012.
Address correspondence to Zinatossadat Hossaini, Department of Chemistry, Qaemshahr Branch, Islamic
Azad University, Qaemshahr, P O Box 163, Mazandaran, Iran. E-mail: zshossaini@yahoo.com
555

556
Z. HOSSAINI ET AL.
several aspects such as variable and high bond-forming efficiency. With a small set of start
materials, very large libraries can be developed within a short time, which can be applied
to research on medicinal chemistry. The first MCR was described in 1850 by the Strecker’s
synthesis of a-amino acids.9a Other MCRs have been described (as examples) successfully
in Hantsch’s synthesis of 1,4-dihydropyridines in 1882,9b Biginelli’s synthesis of 3,4-
dihydropyrimidin-2-ones in 1891,9c Mannich’s synthesis of b-amino carbonyl compounds
in 1912,9d Robinson’s synthesis of alkaloid tropinone in 1917,9e Passerini synthesis of a-
acyloxycarboxamide in 1921,9f Bucherer–Bergs’s synthesis of hydantoins in 1934,9g Ugi’s
synthesis of bis-amide in 1959,9h and Pauson–Khand’s synthesis of a,b-cyclopentenone in
1977.9i
Phosphonates have important applications in flame retardancy,10,11 organic synthe-
sis,12 and biological applications.13 Also, phosphonates have been used as substitutes of
the corresponding esters and acids of high biological activity14,15 and as suitable probes
for designing antibodies on the basis of transition state models. A large number of meth-
ods have appeared describing novel syntheses of organophosphorus compounds.16 In this
paper, another class of products is chromenes. Chromenes have attracted substantial atten-
tion due to their biological activity and their presence in a diversity of significant natural
products.17 The reaction of dialkyl acetylenedicarboxylate and 4-hydroxycumarine in the
presence of trimethyl or triphenyl phosphite leads to phosphonate derivatives 4 in high
yields18 (Scheme 1). This type of reactions in the presence of various catalysts has been
investigated in literatures.19–21
O
OH CO2R
OH
O
CO2R
P(OR')2
H2O
(R'O)3P
+
+
CO2R
70 oC, 5 h
O
O
O
CO2R
2
3
4
1
R'
2, 3, 4
Yield (%) of 4
R
Me
Me
a
Me
Et
85
80
b
c
Ph
Ph
Me
Et
72
68
d
Scheme 1 Reaction of phosphites, activated acetylenes, and 4-hydroxycumarin.
RESULT AND DISCUSSION
1
The H NMR spectrum of 4a displayed signals for vicinal methine protons at δ =
3.92 and 5.12, which appeared as two sets of doublet doublets with 2JHP and 3JHP values
of 20.4 and 8.7 Hz, respectively. The methoxy groups of the phosphoranyl moiety are
diastereotopic and show two separate doublets at δ = 2.92 and 3.72. The hydroxy pro-
ton was observed as a broad singlet at δ = 8.12, which disappeared with addition of D2O.

FUNCTIONALIZED PHOSPHONATES AND CHROMENES
557
CO2Me
Ar
O
O
H
H
(MeO)2P
(MeO)2P
Ar
CO2Me
H
H
CO2Me
CO2Me
(2R, 3S)-4 or (2S, 3R)-4
(2S, 3S)-4 or (2R, 3R)-4
Figure 1 Two diastereomers of 4a with anti arrangement.
Observation of 3JHH = 11.7 Hz for the vicinal methine protons in 4a specifies the supremacy
of anti arrangement. Since compound 4a possesses two stereogenic centers, two diastere-
3
omers with anti HCCH arrangements are possible (Figure 1). The observation of JCP of
21.5 Hz for the CO2Me group and 3JCP of zero for C of naphthalene moiety is in agreement
with the (2R,3S) or (2S,3R) diastereoisomer.18
A proposed mechanism for the formation of compound 4 is shown in Scheme 2.18
Under the reaction conditions, ylide 7 isomerizes to ylide 8 and hydrolysis of 8 leads to
phosphonate derivative 4.
_
O
O
CO2R
_
+
+
P(OMe)3
(MeO)3P
+
C
CHCO2R
H
O
CO2R
RO2C
O
O
O
5
6
7
CO2R
_
OH
OH CO2R
O
+
P(OMe)3
P(OMe)2
moisture
-ROH
CO2R
CO2R
O
O
O
O
8
4
Scheme 2 Proposed mechanism for the formation of 4.
Under similar conditions, the reaction of dialkyl acetylenedicarboxylate 2 and triethyl
phosphite 9 in the presence of 4-hydroxycumarin 1 produces 2,5-dioxo-3,4-dihydro-2H,5H-
pyrano[3,2-c]chromene-4-carboxylate 10 in excellent yield18 (Scheme 3). Compound 10 is
possibly produced through an ylide intermediate similar to 7 (Scheme 2). However, because
of the steric reasons, hydrolysis of this intermediate occurs on phosphorus atom and leads
to a succinate derivatives, which is lactonized to produce 10.
In conclusion, we found that the reaction of activated acetylenic compounds with
trimethyl phosphite, triethyl phosphite, or triphenyl phosphite in the presence of 4-
hydroxycumarin leads to a facile synthesis of some functionalized phosphonates and
chromenes in water as green solvent without using any catalyst.

558
Z. HOSSAINI ET AL.
O
O
OH
O
CO2R
H2O
CO2R
(EtO)3P
+
+
70 oC, 5 h
O
O
O
CO2R
10
9
1
2
Yield (%) of 10
2, 10
R
87
75
a
Me
Et
b
Scheme 3 Reaction of triethyl phosphite, activated acetylenes, and 4-hydroxycumarin.
EXPERIMENTAL
Melting points were measured on an Electrothermal 9100 aparatus. Elemental anal-
yses for the C, H, and N were performed using a Heraeus CHN-O-Rapid analyzer. Mass
spectra were recorded on a FINNIGAN-MATT 8430 spectrometer operating at an ioniza-
tion potential of 70 eV. IR spectra were measured on a Shimadzu IR-460 spectrometer. 1H,
13C, and 31P spectra were measured with a BRUKER DRX-500 AVANCE spectrometer
1
at 500.1, 125.8, and 202.4 MHz, respectively. H, 13C, and 31P spectra were obtained for
solutions in CDCl3 using TMS as internal standard or 85% H3PO4 as external standard.
All the chemicals used in this work were purchased from Fluka (Buchs, Switzerland) and
were used without further purification.
General Procedure for the Preparation of Compounds 4a–d
To a magnetically stirred solution of dialkyl acetylenedicarboxylate 2 (2 mmol) and
4-hydroxycumarin 1 (2 mmol) in H2O (10 mL) was added trimethyl or triphenyl phosphite 3
(2 mmol). The reaction mixture was then stirred for 5 h at 70 ◦C. The completion of reaction
was confirmed by TLC (EtOAc–hexane 6:1). The resulting precipitate was separated by
filtration and was recrystallized from EtOH to afford the pure title compounds.
Dimethyl 2-(Dimethoxyphosphoryl)-3-(4-hydroxy-2-oxo-2H-chromen-3-
◦
yl) succinate (4a). Colorless crystals, mp 185–187 C, 0.70 g, yield 85%. IR (KBr)
(νmax/cm−1): 3235, 1732, 1740, 1754 cm−1. Anal. calcd. for C17H19O10P (414.30): C,
1
49.28; H, 4.62. Found: C, 49.36; H, 4.74%. H NMR (500 MHz, CDCl3): δ 2.92 (3 H, d
3JHP 11.2 Hz, MeO), 3.65 (3 H, s, MeO), 3.72 (3 H, d 3JHP 11.2 Hz, OMe), 3.85 (3 H, s,
2
3
3
3
MeO), 3.92 (1 H, dd JHP 20.4 Hz JHH 11.7 Hz, CH), 5.12 (1 H, dd JHH 11.7 Hz JHP
8.7 Hz, CH), 6.95–7.92 (4 H, m, 4 CH), 8.12 (1 H, s, OH). 13C NMR (125.7 MHz, CDCl3):
1
2
δ 43.8 (CH), 48.2 (d JPC 134.4 Hz, CH), 51.8 (OMe), 52.3 (d JPC 8.2 Hz, MeO), 53.4
(MeO), 54.0 (d, 2JPC 8.2 Hz, MeO), 115.4 (C), 122.4 (CH), 123.8 (C), 125.4 (CH), 126.8
(CH), 127.5 (C), 132.6 (CH), 149.6 (C), 165.2 (C O), 167.5 (d 2JPC 5.4 Hz, C O), 172.6
(d 3JPC 21.5 Hz, C O). 31P NMR (202 MHz, CDCl3): δ 18.6. MS, m/z (%): 414 (M+, 20),
252 (48), 162 (86), 31 (100).

FUNCTIONALIZED PHOSPHONATES AND CHROMENES
559
Diethyl 2-(Dimethoxyphosphoryl)-3-(4-hydroxy-2-oxo-2H-chromen-3-yl)
succinate (4b). White powder, mp 192–194 ◦C, 0.71 g, yield 80%. IR (KBr) (νmax/cm−1):
3242, 1725, 1738, 1746 cm−1. Anal. calcd for C19H23O10P (442.35): C, 51.59; H, 5.24.
Found: C, 51.48; H, 5.18%. 1H NMR (500 MHz, CDCl3): δ 1.34 (3 H, t, 3JHH 7.4 Hz, Me),
1.38 (3 H, t, 3JHH 7.5 Hz, Me), 3.04 (3 H, d 3JHP 11.6 Hz, MeO), 3.75 (3 H, d 3JHP 11.6 Hz,
MeO), 4.02 (1 H, dd 2JHP 21.2 Hz 3JHH 12.4 Hz, CH), 4.21 (2 H, q, 3JHH 7.5 Hz, CH2O),
4.27 (2 H, q, 3JHH 7.4 Hz, CH2O), 5.18 (1 H, dd 3JHH 12.0 Hz 3JHP 9.2 Hz, CH), 6.87–7.90
(4 H, m, 4 CH), 8.09 (1 H, s, OH). 13C NMR (125.7 MHz, CDCl3): δ 13.4 (Me), 14.2 (Me),
44.0 (CH), 48.8 (d 1JPC 135.4 Hz, CH), 51.7 (d 2JPC 8.5 Hz, MeO), 54.6 (d, 2JPC 8.5 Hz,
MeO), 61.7 (CH2O), 62.3 (CH2O), 114.7 (C), 122.5 (CH), 124.3 (C), 125.8 (CH), 127.5
(CH), 128.2 (C), 132.4 (CH), 149.1 (C), 164.3 (C O), 166.8 (d 2JPC 5.8 Hz, C O), 173.2
(d 3JPC 22.3 Hz, C O). 31P NMR (202 MHz, CDCl3): δ 17.8.
Dimethyl 2-(Diphenoxyphosphoryl)-3-(4-hydroxy-2-oxo-2H-chromen-3-
◦
yl) succinate (4c). Pale yellow crystals, mp 204–206 C, 0.77 g, yield 72%. IR (KBr)
(νmax/cm−1): 3238, 1730, 1738, 1745 cm−1. Anal. calcd for C27H23O10P (538.44): C,
60.23; H, 4.31. Found: C, 60.34; H, 4.42%. 1H NMR (500 MHz, CDCl3): δ 3.74 (3 H, s,
MeO), 3.87 (3 H, s, MeO), 4.12 (1 H, dd 2JHP 21.2 Hz 3JHH 12.2 Hz, CH), 5.23 (1 H, dd
3JHH 12.2 Hz 3JHP 9.2 Hz, CH), 7.14–7.96 (14 H, m, 14 CH), 8.05 (1 H, s, OH). 13C NMR
(125.7 MHz, CDCl3): δ 44.2 (CH), 49.5 (d 1JPC 135.8 Hz, CH), 52.0 (OMe), 52.8 (MeO),
3
3
3
121.2 (d, JCP 6.4 Hz, 2 CH), 122.3 (d, JPC 10.2 Hz, C), 123.0 (d, JPC 5.6 Hz, 2 CH),
124.6 (CH), 126.2 (CH), 127.4 (CH), 128.2 (CH), 128.8 (CH), 130.4 (m, 4 CH), 130.8
(CH), 132.4 (C), 132.7 (C), 148.6 (d 2JPC 9.5 Hz, C), 150.8 (m, 2 C), 163.5 (C O), 168.2
(d 2JPC 17.0 Hz, C O), 175.3 (C O).
Diethyl
2-(Diphenoxyphosphoryl)-3-(4-◦hydroxy-2-oxo-2H-chromen-3-
yl) succinate (4d). Yellow powder, mp 212–214 C, 0.76 g, yield 68%. IR (KBr)
(νmax/cm−1): 3242, 1738, 1745, 1752. Anal. calcd for C29H27O10P (566.49): C, 61.49; H,
4.80. Found: C, 61.57; H, 4.86%. 1H NMR (500 MHz, CDCl3): δ 1.36 (3 H, t, 3JHH 7.6 Hz,
Me), 1.42 (3 H, t, 3JHH 7.6 Hz, Me), 4.16 (1 H, dd 2JHP 21.5 Hz 3JHH 12.0 Hz, CH), 4.24 (2
H, q, 3JHH 7.6 Hz CH2O), 4.34 (2 H, q, 3JHH 7.6 Hz, CH2O), 5.27 (1 H, dd 3JHH 12.5 Hz
3JHP 9.6 Hz, CH), 7.16-8.04 (14 H, m, 14 CH), 8.10 (1 H, s, OH). 13C NMR (125.7 MHz,
1
CDCl3): δ 13.2 (Me), 13.8 (Me), 44.6 (CH), 50.2 (d JPC 136.4 Hz, CH), 61.2 (CH2O),
3
3
3
62.3 (CH2O), 121.5 (d, JCP 6.8 Hz, 2 CH), 122.7 (d, JPC 10.6 Hz, C), 123.4 (d, JPC
6.3 Hz, 2 CH), 125.4 (CH), 126.7 (CH), 128.2 (CH), 128.8 (CH), 129.3 (CH), 130.8 (m, 4
CH), 131.3 (CH), 132.9 (C), 133.5 (C), 149.2 (d 2JPC 10.4 Hz, C), 151.3 (m, 2 C), 164.2
(C O), 169.3 (d 2JPC 18.4 Hz, C O), 176.2 (C O).
General Procedure for Preparation of Compounds 10a–b
To a magnetically stirred solution of dialkyl acethylenedicarboxylate 2 (2 mmol) and
4-hydroxycumarin 1 (2 mmol) in water was added triethyl phosphite 9 (2 mmol) slowly. The
reaction mixture was then stirred for 5 h at 70 ◦C. After completion of reaction (monitored
by TLC), the resulting precipitate was separated by filtration and recrystallized from EtOH
to afford the pure title compounds.
Methyl 2,5-Dioxo-3,4-dihydro-2H, 5H-pyrano[3,2-c]chromene-4-carboxy-
◦
late (10a). White powder, mp 130–132 C, 0.48 g, yield 87%., IR (KBr) (νmax/cm−1):
1735, 1757, 1463 cm−1. Anal. calcd for C14H10O6 (274.23): C, 61.32; H, 3.68. Found: C,
61.44; H, 3.76%. 1H NMR (500 MHz, CDCl3): δ 3.02 (1 H, dd 2JHH 15.8 Hz 3JHH 7.4 Hz,
HCH), 3.28 (1 H, dd 2JHH 15.8 Hz 3JHH 2.8 Hz, HCH), 3.78 (3 H, s, MeO), 4.12 (1 H, dd
3JHH 7.4 Hz 3JHH 2.8 Hz, CH), 7.28-7.76 (4 H, m, 4 CH). 13C NMR (125.7 MHz, CDCl3):

560
Z. HOSSAINI ET AL.
δ 31.8 (CH2), 42.2 (CH), 52.8 (MeO), 112.7 (C), 121.5 (CH), 122.6 (C), 126.2 (CH), 128.4
(CH), 134.3 (CH), 152.2 (C), 156.8 (C), 160.4 (C O), 165.4 (C O), 167.3 (C O). MS,
m/z (%): 274 (M+, 15), 243 (86), 162 (64), 31 (100).
Ethyl 2,5-Dioxo-3,4-dihydro-2H, 5H-pyrano[3,2-c]chromene-4-carboxyla-
te (10b). White powder, mp 138–140 ◦C, 0.43 g, yield 75%., IR (KBr) (νmax/cm−1): 1738,
1742, 1753 cm−1. Anal. calcd for C15H12O6 (274.23): C, 62.50; H, 4.20. Found: C, 62.38;
1
3
H, 4.05%. H NMR (500 MHz, CDCl3): δ 1.34 (3 H, t, JHH 7.4 Hz, Me), 2.97 (1 H, dd
2JHH 15.4 Hz 3JHH 7.5 Hz, HCH), 3.25 (1 H, dd 2JHH 15.4 Hz 3JHH 3.0 Hz, HCH), 4.15 (1
H, dd 3JHH 7.3 Hz 3JHH 3.0 Hz, CH), 4.24 (2 H, q, 3JHH 7.4 Hz, CH2O), 7.26-7.78 (4 H, m,
4 CH). 13C NMR (125.7 MHz, CDCl3): δ 13.8 (Me), 32.0 (CH2), 42.5 (CH), 62.4 (CH2O),
113.4 (C), 121.8 (CH), 123.4 (C), 126.7 (CH), 128.7 (CH), 134.6 (CH), 152.5 (C), 157.0
(C), 161.4 (C O), 165.8 (C O), 167.7 (C O).
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