H. Akdas, Gilles Mislin, E. Graf
Mar 12, 1999
Citations
0
Influential Citations
64
Citations
Journal
Tetrahedron Letters
Abstract
The role of alkaline metal cations in the synthesis and in determining the conformer distribution of tetrakis((ethoxycarbonyl)methoxy)tetrathiacalix[4]arene obtained by treatment of tetrathiacalix[4]arene 1 in acetone by ethyl bromoacetate in the presence of M 2 CO 3 was systematically investigated. Among the four possible conformers, the cone, partial cone and 1,3-alternate conformers were obtained, purified and structurally characterised by X-ray analysis in the solid state. Although for Li + no tetra substituted derivative was observed, for Na + the cone conformer was exclusively formed while for both K + and Cs + a mixture of partial cone and 1,3-alternate conformers was obtained.