Abstract
Crystalline complexes of urea and thiourea with crown ethers, have been prepared, viz., 18-crown-6 (18C6), benzo-18-crown-6 (B18C6), dibenzo-18-crown-6 (DB18C6), dicyclohexano-18-crown-6 (DC 18C6) and dibenzo-24-crown-8 (DB24C8). While the complexes of the large ring size crown ether, DB24C8, have high ether to (thio)urea ratios, the stoichiometry of the others lies between one molecule of crown ether and from one to six molecules of (thio)urea. An IR spectral study of the urea and thiourea complexes showed that the behavior of thiourea in these complexes is clearly different from that of urea, indicating the role of sulphur in the interaction of thiourea with crown ethers. The urea and thiourea complexes were classified according to their stoichiometries and their IR spectral behavior into three classes for which credible structures were proposed.
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Host Guest Complex Chemistry of Macrocycles: Synthesis, Structure, Applications, Editors: F. Vögtle and E. Weber, Springer-Verlag, Berlin (1985). (b) A. Elbasyouny, H. J. Brugge, K.V. Deuten, M. Dickel, A. Knöchel, K.U. Koch, J. Kopf, D. Melzer, and G. Rudolph:J. Am. Chem. Soc. 105, 6568 (1983); Y.A. Simonov, T.I. Malinowskii, E.V. Ganin, S.A. Kotlyar, G. Bocelli, G. Calestani, and C. Rizzoli:J. Incl. Phenom. 8, 349 (1990); I.M. Kolthoff, and M.K. Chantooni:Can. J. Chem. 70, 177 (1992); A. Belamri, C. Bavoux, and A. Thozet:J. Incl. Phenom. 8, 383 (1990); Y. Wu, H. An, J. Tao,J. Incl. Phenom. 9, 267 (1990); G.W. Buchana, A. Rodrigue, C. Bensimon, and C.I. Ratcliffe:Can. J. Chem. 70, 1033 (1992). (c) S.R. Salman and S.M. AL-Marsoumi:Spectrochim. Acta 49A, 435, (1993); (1993); G.A.W. Derwish, S.R. Salman, and S.M. AL-Marsoumi:J. Incl. Phenom. 20, 123 (1995).
C.J. Pedersen:J. Org. Chem. 36, 1690 (1971).
F. Vögtle and W.M. Muller: J. Org. Chem. 49, 347 (1984).
J.W.H.M. Uiterwijk, G.J. van Hummel, S. Harkema, V.M.L.J. Aarts, K. Daasvatn, J. Geevers, H.J. Denhertog, and D.N. Reinhoudt:J. Incl. Phenom. 6, 79 (1988).
R.B. Penland, S. Mizushima, C. Columba, and J.V. Quaglino:J. Am. Chem. Soc. 79, 1575 (1957).
A.C. Griffin and J.F. Johnson:J. Am. Chem. Soc. 99, 3460 (1977).
M.C. Etter:Acc. Chem. Res. 23, 120 (1990).
N.B. Colthup, L.H. Daly, and S.E. Wiberly: Introduction to Infrared and Raman Spectroscopy, 3rd ed., Academic Press, U.K. (1990).
N.S. Poonia and M.R. Truter:J. Chem. Soc. 2062 (1973).
C.A. Hunter:Chem. Soc. Rev. 23, 101 (1994).
A.R. Daniewski, U. Dabrowska, Z. Piasek, and T. Urbanski:J. Chem. Soc. 2340 (1962).
Y. Saito, K. Machida, and T. Uno:Spectrochim. Acta 27A, 991 (1971).
J.L. Duncan:Spectrochim. Acta 27A, 1197 (1971).
A. Yamaguchi, R.B. Penland, S. Misushima, T.J. Lan, C. Curran, and J.V. Quaglino:J. Am. Chem. Soc. 80, 527 (1958).
V.D. Brega, A.V. Ablov, and Yu.Ya. Kharitonov:Zh. Neorg. Khim. 15, 3163 (1970).Chem. Abstr 74, 47575j (1971).
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El-Eswed, B.I., Zughul, M.B. & Derwish, G.A.W. Crown ether molecular complexes with urea and thiourea. J Incl Phenom Macrocycl Chem 24, 325–340 (1996). https://doi.org/10.1007/BF01041117
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DOI: https://doi.org/10.1007/BF01041117