Abstract
Exchange kinetics of Ba2+-18-crown-6 complex in deuterated methanol solution was studied by proton NMR line-shape analysis of a series of solutions containing equal population of free and complexed 18-crown-6, but varying concentration of the macrocycle, at various temperatures. From −33 to 37°C, the predominant mechanism for the exchange of the ligand between the two sites is a bimolecular pathway which is characterized by the following activation parameters:E a=47±2 kJ-mol−1; ΔH ≠=45±2 kJ-mol−1; ΔS ≠=−8±4 J-mol−1-K−1. However, the contribution of a dissociative mechanism with activation parametersE a=36±5 kJ-mol−1, ΔH ≠=33±5 kJ-mol−1 and ΔS ≠=104±18 J-mol−1-K−1 becomes more important at higher temperatures.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
R. M. Izatt, J. S. Bradshaw, S. A. Nielsen, J. D. Lamb, J. J. Christensen, and D. Sen,Chem. Rev. 85, 271 (1985).
R. M. Izatt, K. Pawlak, J. S. Bradshaw, and R. L. Bruening,Chem. Rev. 91, 1721 (1991).
M. Shamsipur,Iran. J. Chem. & Chem. Eng. 1 (Nos. 10 and 11), 59 (1988).
L. J. Rodriguez, G. W. Liesegang, M. M. Farrow, N. Purdie, and E. M. Eyring,J. Phys. Chem. 82, 647 (1978).
P. B. Chock,Proc. Natl. Acad. Sci. U.S.A. 69, 1939 (1972).
W. Walace, E. M. Eyring, and S. Petrucci,J. Phys. Chem. 88, 6353 (1984).
E. Eigen and R. Winkler,In the Neuroscience: Second Study Program, F. D. Schmitt, ed., (Rockfeller University, New York, 1970).
B. O. Strasser, M. Shamsipur, and A. I. Popov,J. Phys. Chem. 89, 4822 (1985).
M. Shamsipur and A. I. Popov,J. Phys. Chem. 90, 5997 (1986).
P. Szezygiel, M. Shamsipur, K. Hallenga, and A. I. Popov,J. Phys. Chem. 91, 1252 (1987).
M. Shamsipur and A. I. Popov,J. Phys. Chem. 91, 447 (1987).
M. Shamsipur and A. I. Popov,J. Phys. Chem. 92, 147 (1988).
M. K. Amini and M. Shamsipur,J. Phys. Chem. 95, 9601 (1991).
A. Rouhollahi, M. K. Amini, and M. Shamsipur,J. Solution Chem. 23, 63 (1994).
J. Ghasemi and M. Shamsipur,Polyhedron 15, 923 (1996).
G. W. Gokel, D. J. Cram, C. L. Liotta, H. P. Harris, and F. L. Cook,Org. Synth. 56, 30 (1977).
J. A. Pople, W. G. Schneider, and H. J. Bernstein,High Resolution Nuclear Magnetic Resonance (McGraw-Hill, New York 1959), p. 218.
Y. M. Cahen, J. L. Dye, and A. I. Popov,J. Phys. Chem. 79, 1292 (1975).
M. J. D. Powell,Comput. J. 7, 155 (1964).
S. Kashanian and M. Shamsipur,Inorg. Chim. Acta 155, 203 (1989).
J. D. Lamb, R. M. Izatt, S. W. Swain and J. J. Christensen,J. Am. Chem. Soc. 102, 475 (1980).
E. Shchori, J. Jagur-Grodzinski, Z. Luz, and M. Shporer,J. Am. Chem. Soc. 93, 7133 (1971).
E. Shchori, J. Jagur-Grodzinski, and M. Shporer,J. Am. Chem. Soc. 95, 3842 (1973).
S. H. Lin, K. P. Li, and H. Eyring, inPhysical Chemistry, an Advanced Treatise Vol. VII, H. Eyring, D. Handerson, and W. Yost, eds., (Academic Press, New York, 1977), p. 1.
V. Gutmann,Coordination Chemistry in Nonaqueous Solutions (Springer, Vienna, 1968).
E. Schmidt and A. I. Popov,J. Am. Chem. Soc. 105, 1873 (1983).
K. M. Briere and C. Detellier,J. Phys. Chem. 96, 2185 (1992).
A. Delville, H. D. H. Stover and C. Detellier,J. Am. Chem. Soc. 109, 7293 (1987).
K. M. Briere and C. Detellier,New J. Chem. 13, 145 (1989).
B. O. Strasser and A. I. Popov,J. Am. Chem. Soc. 107, 7921 (1985).
J. C. Lockhart, M. B. McDonnell, M. N. Stuart Hill, and M. Todd,J. Chem. Soc., Perkin Trans. II 1915 (1989).
Y. Marcus,J. Solution Chem. 15, 291 (1986).
R. D. Shannon,Acta Crystalogr. 32 A, 751 (1970).
C. J. Pedersen,J. Am. Chem. Soc. 92, 386 (1970).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Alizadeh, N., Shamsipur, M. Nuclear magnetic resonance study of the ligand interchange of Ba2+-18-crown-6 complex in methanol solution. J Solution Chem 25, 1029–1039 (1996). https://doi.org/10.1007/BF00972597
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00972597