TORAND SYNTHESIS BY TRIMERIZATION - NEW RECEPTORS FOR GUANIDINIUM

The largest cycloarene derivative reported so far, the torand 1, is surprisingly readily accessible by CsOH‐mediated cyclotrimerization. According to Macromodel calculations, 1 is almost planar and binds guanidinium with formation of six almost ideal hydrogen bonds with only slight change in conformation: the UV spectra of the torand and of its guanidinium complex are almost identical. (Figure Presented.) Copyright © 1990 by VCH Verlagsgesellschaft mbH, Germany