Abstract
The reactions between alkali metal ions and crown ethers, aza crown ethers, and cryptands in propylene carbonate were studied by potentiometric and calorimetric titrations. The most stable complexes formed by macrocyclic and macrobicyclic ligands are when the ligand and cation dimensions are comparable. On comparing the complex stabilities of crown ethers and aza crown ethers of the same size, crown ethers were, on the whole, found to form the most stable complexes, with the exception of the lithium cation. Enthalpic factors are responsible. Substitution of the amino group protons of the aza crown ethers by benzyl groups leads to a high increase in values of the reaction enthalpy. This effect is partly compensated by entropic contributions. The bulky benzyl groups reduce the ligand solvent interactions and induce a ligand conformation with the lone pair of electrons from the nitrogen donor atoms which are more or less directed inside the cavity. The thermodynamic data for the transfer from methanol to propylene carbonate indicate that the ligands containing nitrogen show specific interactions with methanol.
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. D. Boss and A. I. Popov:Inorg. Chem.25, 1747 (1986).
H.-J. Buschmann:J. Solution Chem. 17, 277 (1988).
F. Eggers, T. Funck, K. H. Richmann, H. Schneider, E. M. Eyring, and S. Petrucci:J. Phys. Chem. 91, 1961 (1987).
E. Schmidt, J.-M. Tremillon, J.-P. Kintzinger, and A. I. Popov:J. Am. Chem. Soc. 105, 7563 (1983).
Y. Marcus:Ion Solvation, J. Wiley, Chichester (1985).
H. Tsukube, K. Takagi, T. Higashiyama, T. Iwachido, and N. Hayama:J. Chem. Soc. Perkin Trans. I, 1033 (1986).
V. J. Gatto, K. A. Arnold, A. M. Viscariello, S. R. Miller, and G. W. Gokel:Tetrahedron Lett. 27, 327 (1986).
D. N. Bhattacharyya, C. L. Lee, J. Smid, and M. Szwarc:J. Phys. Chem. 69, 608 (1965).
J. J. Christensen, J. Ruckman, D. J. Eatough, and R. M. Izatt:Thermochim. Acta 3, 203 (1972).
D. J. Eatough, J. J. Christensen, and R. M. Izatt:Thermochim. Acta 3, 219 (1972).
D. J. Eatough, R. M. Izatt, and J. J. Christensen:Thermochim. Acta 3, 233 (1972).
H.-J. Buschmann:Z. Phys. Chem. (Frankfurt am Main)139, 113 (1984).
J. Gutknecht, H. Schneider, and J. Stroka:Inorg. Chem. 17, 3326 (1978).
H.-J. Buschmann:Polyhedron 7, 721 (1988).
A. J. Smetana and A. I. Popov:J. Chem. Thermodynamics 11, 1145 (1979).
M. K. Chantooni and I. M. Kolthoff:J. Solution Chem. 14, 1 (1985).
A. I. Smetana and A. I. Popov:J. Solution Chem. 9, 183 (1980).
A. F. Danil de Namor and L. Ghousseini:J. Chem. Soc. Faraday Trans. 1,81, 781 (1985).
G. W. Gokel, D. M. Goli, C. Minganti, and L. Echegoyen:J. Am. Chem. Soc. 105, 6786 (1983).
H.-J. Buschmann: inStereochemistry of Organometallic and Inorganic Compounds, Vol. 2, I. Bernal (ed.), Elsevier, Amsterdam, p. 103 (1987).
Y. Marcus:J. Solution Chem. 15, 291 (1986).
E. Mei, A. I. Popov, and J. L. Dye:J. Am. Chem. Soc. 99, 6532 (1977). E. Mei, L. Liu, J. L. Dye, and A. I. Popov:J. Solution Chem. 6, 771 (1977).
H.-J. Buschmann:Inorg. Chim. Acta 125, 31 (1986).
Y. Marcus:Pure Appl. Chem. 55, 977 (1983). Y. Marcus:Pure Appl. Chem. 57, 1103 (1985).
B. G. Cox, P. Firman, H. Horst, and H. Schneider:Polyhedron 2, 343 (1983).
M. H. Abraham and H. C. Ling:J. Chem. Soc., Faraday Trans. I,80, 3445 (1984).
N. K. Dalley: inSynthetic and Multidentate Macrocyclic Compounds, R. M. Izatt and J. J. Christensen (eds.), Academic Press, p. 207 (1978).
J.-M. Lehn:Struct. Bonding (Berlin)16, 1 (1973).
R. D. Shannon and C. T. Prewitt:Acta Crystallogr. B25, 925 (1969).
Author information
Authors and Affiliations
Additional information
This paper is dedicated to Professor H. Strehlow on the occasion of his 70th birthday.
Rights and permissions
About this article
Cite this article
Buschmann, HJ. The complexation of alkali metal ions by crown ethers, aza crown ethers, and cryptands in propylene carbonate. J Incl Phenom Macrocycl Chem 7, 581–588 (1989). https://doi.org/10.1007/BF01084708
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01084708