Tautomeric behaviors of 5-arylazobarbituric acids in different concentrations
الموضوعات : Journal of the Iranian Chemical Research
Nader Noroozi Pesyan
1
(Department of Chemistry, Faculty of Science, Urmia University, 57159, Urmia, Iran)
Jabbar Khalafy
2
(Department of Chemistry, Faculty of Science, Urmia University, 57159, Urmia, Iran)
Karim Akbari Dilmaghani,
3
(Department of Chemistry, Faculty of Science, Urmia University, 57159, Urmia, Iran)
Saeed Rastgar,
4
(Department of Chemistry, Faculty of Science, Urmia University, 57159, Urmia, Iran)
Zahra Malekpoor,
5
(Department of Chemistry, Faculty of Science, Urmia University, 57159, Urmia, Iran)
Mina Mohammadzadeh
6
(Department of Chemistry, Faculty of Science, Urmia University, 57159, Urmia, Iran)
الکلمات المفتاحية: Azo-hydrazone tautomerism, Solvatochromic dyes, 5-Arylazobarbituric acids, Bifurcated intramolecular hydrogen bond,
ملخص المقالة :
The NMR spectra of azo dyes, 5-arylazobarbituric (5a-g), 5-arylazo-1,3-dimethylbarbituric(6a-g) and 5-arylazothiobarbituric acids (7a-g) were studied in DMSO-d6 in differentconcentrations. An intramolecular hydrogen bond was observed and indicating that thehydrazone forms is mostly predominant. The peak of the hydrazone proton was severelybroadened and its chemical shift appeared at down field due to intramolecular hydrogen bond.Existence of nitro group at ortho-position on phenyl ring caused the chemical shift value of theproton of hydrazone form in 5a-7a to be more deshielded than other hydrazone protons in 5bg−7b-g due to bifurcated intramolecular hydrogen bond and anisotropic ring-current effect. Dyes6 shows two tautomers in NMR time scale at low concentration in DMSO-d6.
[1] H. Zollinger, Color Chemistry, Synthesis, Properties and Application of Organic Dyes and Pigments,
3th Edition, Wiley VCH, Weinheim, 2003, Chapters 12-14, pp. 413-537.
[2] P. Gregory, High-Technology Applications of Organic Colorants, Plenum press, New York, 1991,
Chapters 3-5, pp. 27-52.
[3] G. Viscardi, P. Quagliotto, C. Barolo, G. Caputo, G. Digilio, I. Degani, E. Barni, Dyes and Pigments
57 (2003) 87.
[4] N. Haralampus-Grinaviski, L.J. Johnson, M.A. Firestone, Macromolecules 38 (2005) 8971.
N. Noroozi et al. / J. Iran. Chem. Res. 2 (2009) 133-144
144
[5] C.W. Lester, Am. J. Surg. 43 (1939) 153.
[6] S.M. Parmerter, Org. React. 10 (1959) 1.
[7] P. Gregory, Dyes and Pigments 7 (1986) 45.
[8] R.L. Reeves, R.S. Kaiser, J. Org. Chem. 35 (1970) 3670.
[9] K. Hamada, S. Take, T. Iijima, S. Amiya, J. Chem. Soc., Faraday trans. 82 (1986) 3141.
[10] C. Ouyang, S. Chen, B. Che, G. Xue, Colloids and Surface A: Physicochem. Eng. Aspects 301
(2007) 346.
[11] M. Dakiky, K. Kanan, M. Khamis, Dyes and Pigments 41 (1999) 199.
[12] A.H. Berrie, P. Hampson, S.W. Longworth, A. Mathias, J. Chem. Soc. B (1968) 1308.
[13] P. Ŝimůnek, V. Bertolasi, A. Lyčka, V. Mecháček, Org. Biomol. Chem. 1 (2003) 3250.
[14] A. Lyčka, D. Šnobl, V. Macháček, M. Večeřa, Org. Magn. Reson. 16 (1981) 17.
[15] V. Macháček, A. Lyčka, P. Šimůnek, T. Weidlich, Magn. Reson. Chem. 38 (2000) 293.
[16] A. Lyčka, D. Šnobl, V. Macháček, M. Večeřa, Org. Magn. Reson. 15 (1981) 390.
[17] L.A. Fedorov, M.S. Zhukov, N.V. Korsakova, Y.M. Dedkov, A.N. Ermakov, Russian Chem. Bull.
38 (1984) 1612.
[18] A. Lyčka, Dyes and Pigments 43 (1999) 27.
[19] A. Lyčka, Z. Vrba, M. Vrba, Dyes and Pigments 47 (2000) 45.
[20] R.R. Hsieh, D. De'silet, P.M. Kamaier, Dyes and Pigments 14 (1990) 165.
[21] X. Jun, Z. Zheng-Hua, L. Yi-Xin, Dyes and Pigments 16 (1991) 11.
[22] K. Hamada, M. Nishizawa, M. Miitsuishi, Dyes and Pigments 16 (1991) 165.
[23] A.R. Monahan, N.J. Germano, D.F. Blossey, J. Phys. Chem. 75 (1971) 1227.
[24] A. Vogel, Textbook of Practical Organic Chemistry including Qualitative Organic Analysis
(VOGELE’S), 4th Edition, New York, Longman, 1978.
[25] T. Steiner, Angew. Chem. Int. Ed. 41 (2002) 48.
[26] I. Huc, Eur. J. Org. Chem. (2004) 17.
[27] J.C. McDonald, G.M. Whitesides, Chem. Rev. 94 (1994) 2383.
[28] V. Bertolasi, P. Gilli, V. Ferretti, G. Gilli, New J. Chem. 25 (2001) 408.
[29] M. Dakiky, I. Němcova, Dyes and Pigments 40 (1999) 141.
