An efficient route to new 1,2,4,3-triazaphosphole-3-oxide derivatives

Article abstract of DOI:10.1080/10426500903567521

The condensation of hexamethylphosphorotriamide and bis-(dimethylamino) methylphosphonate with amidrazones 1 constitutes a new route to the synthesis of 1,2,4,3-triazaphosphole-3-oxide derivatives 3. Structures of all the synthesized compounds have been established by NMR (¹H, ¹³C, ³¹P) and IR spectroscopy, as well as by elemental analysis and MS spectral data for some products. Copyright Taylor & Francis Group, LLC.

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Phosphorus, Sulfur, and Silicon and the
Related Elements
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An Efficient Route to New 1,2,4,3-
Triazaphosphole-3-Oxide Derivatives
M. Smadhi a & R. Abderrahim a
a Laboratory of Organic Synthesis, Department of Chemistry, Faculty
of Science , University of Bizerte , Zarzouna, Bizerte, Tunisia
Published online: 05 Nov 2010.
To cite this article: M. Smadhi & R. Abderrahim (2010) An Efficient Route to New 1,2,4,3-
Triazaphosphole-3-Oxide Derivatives, Phosphorus, Sulfur, and Silicon and the Related Elements,
185:11, 2229-2232
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Phosphorus, Sulfur, and Silicon, 184:2229–2232, 2010
Copyright ꢀC Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426500903567521
AN EFFICIENT ROUTE TO NEW
1,2,4,3-TRIAZAPHOSPHOLE-3-OXIDE DERIVATIVES
M. Smadhi and R. Abderrahim
Laboratory of Organic Synthesis, Department of Chemistry, Faculty of Science,
University of Bizerte, Zarzouna, Bizerte, Tunisia
The condensation of hexamethylphosphorotriamide and bis-(dimethylamino) methylphos-
phonate with amidrazones 1 constitutes a new route to the synthesis of 1,2,4,3-
triazaphosphole-3-oxide derivatives 3. Structures of all the synthesized compounds have
been established by NMR (1H, 13C, 31P) and IR spectroscopy, as well as by elemental
analysis and MS spectral data for some products.
Keywords Amidrazones; bis-(dimethylamino) methylphosphonate; hexamethylphosphorotri-
amide; triazaphosphole
INTRODUCTION
The synthesis of phosphonitrogenous heterocycles1–3 is one of the aims of researchers
in synthetic organic chemistry because of their large biological and pharmaceutical ac-
tivities.3–6 Triazaphosphole derivatives are a family of heterocyclic compounds that has
attracted the interest of chemists due to their various applications as antibacterials4 and
cytoxicity4 agents.
There are various methods7–12 for the synthesis of 1,2,4,3-triazaphospholes, but most
of them suffer from one or more disadvantages, such as the triazaphosphole derivatives can
exist in several different isomeric forms depending on the type of substitution. We report
in this article the selective synthesis of new triazaphosphole derivatives 3 by the reac-
tion of amidrazones 1 with hexamethylphosphorotriamide or bis-(dimethylamino) methyl
phosphonate.
RESULTS AND DISCUSSION
2-Aminobenzamidrazones 1, which are the starting material for this work, were
prepared from the condensation of hydrazine with 2-aminobenzonitrile in the presence of a
catalytic amount of acetic acid. The chemical structure of compound 1 is in agreement with
its spectral data. The IR spectrum of compound 1 exhibited the absorption bands for NH2
Received 26 October 2009; accepted 14 December 2009.
Address correspondence to R. Abderrahim, Laboratory of Organic Synthesis, Department of Chemistry,
Faculty of Science, University of Bizerte, 7021 Zarzouna, Bizerte, Tunisia. E-mail: abderrahim raoudha@yahoo.fr
2229

2230
M. SMADHI AND R. ABDERRAHIM
O
R1
NH2
NH2
P(NMe2)2
H
-2
N
NHMe2
/
NH2
P
O
R1
3
1
N
N-NHR
N
R
3c
3b
3a
H
3d
H
3e
3f
3
R
Me
Ph
Me Ph
R1
NMe NMe NMe Me Me Me
2 2 2
Figure 1 Synthetic route of the formation of compound 3.
and C N (imine) and the absence of an absorption band of a CN group. 1H NMR analysis
confirmed the formation of compound 1 and showed the presence of new signals assigned
to NH2, NH, and protons of the methyl and phenyl introduced by the substituted hydrazine.
13C NMR spectra showed the total absence of a signal related to CN (nitrile) group.
The reaction of compound 1 with phosphorylated reagents in dry toluene under reflux
afforded triazaphosphole 3 (Figure 1).
The formation of triazaphospholes 3 was confirmed by 1H, 13C, and 31P NMR spectra
and IR spectroscopy as well as elemental analysis for some products (3c and 3d). The 31P
NMR spectra showed the presence of a signal corresponding to phosphonate moiety (P O)
at 25 ppm when R1 = NMe2 and a signal at 38 ppm when R1 = Me.
The IR spectrum of 3 showed absorption bands at 3230–3150 cm−1 (NH2), 3350 cm−1
(NH), 1296–1308 cm−1 (P O bonded) and strong bands in the region of 1090–1100 cm−1
indicating the presence of P-N groups. The 1H NMR spectrum of 3 revealed the presence of
two types of methyl group protons in NMe2 with different chemical shifts. Furthermore, the
Me group protons of NMe2 groups coupled with phosphorus and were split into a doublet.
The 13C NMR spectra of 3 displayed the characteristic signals of all carbons and revealed
two signals attributable to the carbons of P-N(CH3)2 of the two non-equivalent methyls of
the NMe2 group.
EXPERIMENTAL
IR spectra were recorded on Perkin Elmer Paragon 1000 PC spectrometer using a
solution of CHCl3. The spectra resolution was 4 cm−1
.
1H, 13C, and 31 P NMR spectra were recorded in CDCl3 as solvent containing TMS
(tetramethylsilane) on a Bru¨ker 300 spectrometer (1H: 300 MHz, 13C: 75.47 MHz, 31P:
121.49 MHz). The chemical shifts (δ)) are reported in ppm relative to TMS (internal
reference) for 1H and 13C and relative to 85% H3PO4 (external reference) for 31P.
Melting points were determined using a Bu¨chi melting point apparatus and are un-
corrected. Elemental microanalysis was performed on a Perkin-Elmer CHN-2400 analyzer
apparatus.

NEW 1,2,4,3-TRIAZAPHOSPHOLE-3-OXIDE DERIVATIVES
2231
Synthesis of 2-Aminobenzamidrazones 1
To a solution of anthranilonitrile (0.01 mol) in ethanol (10 mL), hydrazine (0.015 mol)
and a few drops of acetic acid were added. The reaction mixture was refluxed for 12 h and
then allowed to reach room temperature. The solvent was evaporated from the vacuum
pump, and the resulting solid was filtered, washed several times with diethyl ether, and
recrystallized from ethanol. Compound 1a obtained was chromatographed on a silica gel
column using a mixture of ethyl acetate and petroleum ether (4:6) as eluent.
1a: Mp = 50◦C. Yield = 93%. IR (CHCl3), ν (cm−1): ν (NH2) = 3320–3400; ν
(NH) = 3460. 1H NMR (CDCl3): δ 4.38 (s, 6H, NH2); 6.60–7.28 (m, 4H, Harom). 13C NMR
(CDCl3): δ 115.23; 117.75; 117.90; 132.32; 134.04; 149.78.
1b: Mp = 52◦C. Yield = 94%. IR (CHCl3), ν (cm−1): ν (NH2) = 3320–3400, ν
1
(NH) = 3455. H NMR (CDCl3): δ 4.60 (broad s, 5H, NH, NH2); 3.10 (s, 3H, CH3);
6.40–7.25 (m, 4H, Harom). 13C NMR (CDCl3): δ 38.60; 117.34; 118.48; 128.50; 129.29;
131.98; 146.85; 150.78.
1c: Oil. Yield = 90%. IR (CHCl3), ν (cm−1): ν (NH2) = 3325–3400, ν (NH) =
1
3465. H NMR (CDCl3): δ 4.30 (broad s, 5H, NH, NH2); 6.40–7.25 (m, 9H, Harom). 13C
NMR (CDCl3): δ 115.34, 118.00, 119.43, 119.77, 128.50, 129.29, 131.98, 134.56, 146.85,
151.42.
Synthesis of 1,2,4,3-Triazaphosphole-3-oxide Derivatives
A
mixture of aminobenzamidrazone
1
(1.0 mmol) and hexamethyl-
phosphorotriamide or bis-(dimethylamino) methylphosphonate (1.0 mmol) dissolved in
anhydrous toluene (10 mL) was heated under reflux for 24 h. After evaporating off the
solvent in vacuum, the resulting solid product was recrystallized from CCl4 (3c, 3d, 3e,
3f), and the oil obtained (3a and 3b) was purified by column chromatography using silica
gel (60–120 mesh) with ethyl acetate:petroleum ether (3:7) as eluent.
3a: Oil. Yield = 60%. IR (CHCl3), ν (cm−1): ν (C N) = 1635; ν (NH2) = 3230–3150;
ν (NH) = 3350; ν (P O) = 1296. 1H NMR (CDCl3): δ 2.35 (d, 3JPH = 5.5 Hz, 3H, N-CH3);
2.52 (d, 3JPH = 5.5 Hz, 3H, N-CH3); 4.81 (broad s, 4H, NH, NH2); 6.50–7.16 (m, 4Harom).
2
2
13C NMR (CDCl3): δ 35.88 (d, JPC = 9.2 Hz, NCH3); 36.22 (d, JPC = 6.0 Hz, NCH3);
115.22; 116.11; 117.53; 131.42; 133.30; 150.74; 169.96. 31P NMR (CDCl3): δ 25.09. Calcd
for C9H14N5PO:%C: 45.18;%H: 5.85;%N: 29.28; found:%C: 45.10;%H: 5.80;%N: 29.15.
3b: Oil. Yield = 70%. IR (CHCl3), ν (cm−1): ν (C N) = 1630; ν (NH2) =
1
3
3235–3120; ν (NH) = 3350; ν (P O) = 1296. H NMR (CDCl3): δ 2.38 (d, JPH = 4.9
Hz, 3H, N-CH3); 2.50 (d, 3JPH = 4.9 Hz, 3H, N-CH3); 3.20 (s, 3H, N-CH3); 4.80 (broad s,
3H, NH2, NH); 6.05–7.16 (m, 4Harom). 13C NMR (CDCl3): δ 35.70 (d, JPC = 3.0 Hz,
2
NCH3); 36.12 (d, 2JPC = 7.0 Hz, NCH3); 39.70 (NCH3); 116.25; 116.59; 116.92; 130.65;
133.31; 149.44; 169.00. 31P NMR (CDCl3): δ 25.60. m/e (Relative intensity)%: 253 (5);
193 (50); 165 (20); 150 (30); 135(47); 109(35); 92(42); 76(14).
3c: Mp: 175◦C. Yield = 73%. IR (CHCl3), ν (cm−1): ν (C N) = 1635; ν (NH2) =
3230–3140; ν (NH) = 3330; ν (P O) = 1296. 1H NMR ((CDCl3): δ 2.22 (d, 3JPH = 5.0 Hz,
3H, N-CH3); 2.10 (d, 3JPH = 4.9 Hz, 3H, N-CH3); 5.00 (broad s, 3H, NH2, NH); 6.10–7.20
(m, 4Harom). 13C NMR (CDCl3) : δ 36.07 (d, JPC = 6.0 Hz, NCH3); 36.12 (d, JPC
=
2
2
7 Hz, NCH3); 111.59; 116.11; 117.63; 122.34; 128.04; 128.53; 129.17; 140.42; 147.06;
164.72. 31P NMR (CDCl3): δ 25.10. Calcd for C15H18N5PO:%C: 57.14;%H: 5.71;%N:
22.22; found:%C: 57.00;%H: 5.68;%N: 22.00.

2232
M. SMADHI AND R. ABDERRAHIM
3d: Mp: 180◦C. Yield = 80%. IR (CHCl3), ν (cm−1): ν (C N) = 1635; ν (NH) =
3354; ν (NH2) = 3230–3150; ν (P O) = 1308. 1H NMR (CDCl3): δ 1.30 (d, 2JPH = 11.0 Hz,
3H, P-CH3); 4.72 (broad s, 3H, NH2, NH); 6.60–7.70 (m, 4Harom). 13C NMR (CDCl3): δ
13.12 (NCH3); 114.82; 117.77; 118.98; 119.30; 131.70; 134.33; 145.00; 150.27. 31P NMR
(CDCl3): δ 38.08. Calcd for C8H11N4PO:%C: 45.71;%H: 5.23;%N: 26.66; found:%C:
45.60;%H: 5.20;%N: 26.56.
3e: Mp: 200◦C. Yield = 80%. IR (CHCl3), ν (cm−1): ν (C N) = 1630; ν (NH) =
3354; ν(NH2) = 3230–3140; ν (P O) = 1308. 1H NMR (CDCl3): δ 1.30 (d, 2JPH = 10.0Hz,
3H, P-CH3); 2.60 (s, 3H, N-CH3); 4.90 (broad s, 3H, NH2, NH); 6.50–7.60 (m, 4Harom). 13
C
NMR (CDCl3): δ 11.72 (NCH3); 28.98; 115.17; 117.83; 121.12; 131.90; 133.90; 143.77;
150.54. 31P NMR (CDCl3): δ 38.80. MS: m/e (Relative intensity)%: 224(1); 209 (55);
162(10); 150(30); 135(37); 109(30); 92(48); 76(24).
3f: Mp: 192◦C. Yield = 82%. IR (CHCl3), ν (cm−1): ν (C N) = 1632; ν (NH) =
3350; ν(NH2) = 3225–3130; ν (P O) = 1307. 1H NMR (CDCl3): δ 1.32 (d, 2JPH = 12.0
Hz, 3H, P-CH3); 4.68 (broad s, 3H, NH2, NH); 6.62–7.31 (m, 9Harom). 13C NMR (CDCl3):
δ 14.24 (NCH3); 116.80; 119.71; 121.36; 128.81; 131.3; 133.35; 142.01; 148.78. 31P NMR
(CDCl3): δ 34.20.
REFERENCES
1. B.-A. Song, Y.-L. Wu, S. Yang, D.-Y. Hu, X.-Q. He, and L.-H. Jin, Molecules, 8, 186–192 (2003).
2. L. Wan, I. Alkorta, J. Elguero, J. Sun, and W. Zheng, Tetrahedron, 63, 9129–9133 (2007).
3. R. M. Abdel-Rahman, Trends Heterocycl. Chem. (Indian), 8, 187–195 (2002).
4. A. T. El-Sayed, Eur. Eur, 44(11), 4539–4546 (2009).
5. L. Wan, I. Alkorta, J. Elguero, J. Sun, and W. Zheng, Tetrahedron, 63, 9129–9133 (2007).
6. J.-L. Pirat, J. Monbrun, D. Virieux, and H.-J. Cristau, Tetrahedron, 61, 7029–7036 (2005).
7. M. Hadded, F. Dahan, J. P. Legros, L. Lopez, M.-T. Boidson, and J. Barrans, J. Chem. Soc.
Perkin. Trans. 2, 671–678 (1992).
8. M. Hadded, M.-T. Boisdon, and J. Barrans, J. Soc. Chim. Tunisie, 3, 75–88 (1991).
9. M. Hadded, J. P. Legros, L. Lopez, M.-T. Boidson, and J. Barrans, Phosphorus, Sulfur, and
Silicon, 69, 189–196 (1992).
10. Y. Charbonnel and J. Barrans, Tetrahedron, 32, 2039–2043 (1976).
11. R. Abderrahim, Phosphorus, Sulfur, and Silicon, 182, 893–897 (2007).
12. R. Abderrahim and K. Boujlel, Phosphorus, Sulfur, and Silicon, 180, 79–84 (2005).