Kinetic of iodination of phenol and substituted phenols by pyridinium iodochloride in methanol

Journal of the Iranian Chemical Research

مقاله 8، دوره 2، شماره 2، شهریور 2009، صفحه 151-156   

نویسندگان

Yeshwant B. Vibhute^* ؛ Sandeep V. Khansole

P.G. Department of Chemistry, Yeshwant Mahavidyalaya, Nanded-431 602, India.

چکیده

The kinetics of iodination of the phenol and substituted phenols using pyridinium
iodochloride in methanol has been studied under varying conditions. The rates show first order
kinetics each in pyridinium iodochloride and phenols. The rates of reactions are measured at
different temperature and activation parameters for all phenols computed. Hammett plot is found
to be valid and the corrletion between the enthalpies and free energies of activations is
reasonably linear with an isokinetic temperature 359.55 K. Similarly log A values of all the
phenols are optimized corresponding to Ea of phenols through the equation, log A = log kobs + Ea
/ 2.303 RT.

کلیدواژه‌ها

Kinetics؛ Iodination؛ phenols؛ Pyridinium iodochloride

مراجع

[1] A.Bachi, F. Foubelo, M.Yus, Tetrahedron 50 (1994) 5139.
[2] G.A. Olah, Q. Wang, G. Sanford, G.K.S. Prakash, J. Org. Chem. 58 (1993) 3194.
[3] R.C. Larock, E.K. Yum, J. Am. Chem. Soc. 113 (1991) 6689.
[4] R.C. Larock, N.H. Lee, J. Org. Chem. 56 (1991) 6253.
[5] E.C. Taylor, G.S.K. Wong, J. Org. Chem. 54 (1989) 3618.
[6] W.C. Eckelman, H.R. Adams, C.H. Paik, Int. J. Nucl. Med. Biol. 11 (1984) 163.
[7] (a) C.A. Busacca, R.E. Johnson, Tetrahedron Lett. 33 (1992) 165, (b) J.S. Swenton, A. Callinan, S.J.
Wang, J. Org. Chem. 57 (1992) 78.
[8] K.C. Nicolaou, Angew. Chem. Int. Ed. Engl. 32 (1993) 1377.
[9] N.D. Heindel, H.D. Burns, T. Honds, L.W. Brandy, Chemistry of Radiopharmaceuticals; Eds., Masson;
New York, 1997.
[10] B.S. Painter, F.G. Soper, J. Chem. Soc. (1947) 342.
[11] E. Berliner, J. Am. Chem. Soc. 73 (1951) 4307.
[12] G.V. Shashidhar, N. Sataynarayana, E.V. Sundaram, Ind. J. Chem. 25 (1986) 289.
[13] P.S. Radhakrishnamurthy, R. Janaradhana, Indian. J. Chem. 19A (1980) 333.
[14] (a) H. Firouzabadi, N. Iranpoor, M. Shiri, Tetrahedron Lett. 44 (2003) 8781, (b) A.S. Castanet, F.
Colobert, P.E. Broutio, Tetrahedron Lett. 43 (2002) 5047, (c) G.W. Kabalka, A.R. Mereddy,
Tetrahedron Lett. 45 (2004) 343, (d) K.V.V. Krishna Mohan, N. Narendre, S.J. Kulkarni, Tetrahedron
Lett. 45 (2004) 8015.
[15] P. Sykes, A Guidebook to Mechanism in Organics Chemistry, Orient Longman, 6th Edition, 1981.
[16] H.A. Muathem, J. Chem. Res. 5 (1994) 405.
[17] B. Thimme Gowda, M.C. Mary, Indian J. Chem. 40A (2001) 1196.
[18] O. Exner, Nature 201 (1964) 488.
[19] O. Exner, J.R. Streitwiser, R.W. Talt, Progress in Physical Organic Chemistry, John Wiley, New
York, 1973.
[20] G.V. Shashidhar, N. Satyandraya, E.V. Sundaram, Indian J. Chem. 25A (1986) 289.