ChemInform Abstract: Synthesis and Conformational Studies of Calixarene‐Analogous Trihydroxy(3.3.3)metacyclophanes and Their O‐Alkylated Derivatives.

Abstract

Synthesis and Conformational Studies of Calixarene-Analogous Trihydroxy(3.3.3)metacyclophanes and Their O-Alkylated Derivatives.-The metacyclophane (III) is prepared in six steps from p-tert-butylanisole in 25% yield and de-tert-butylated to give the desired metacyclophane (IV). Weak intramolecular hydrogen bonding is observed in these triols. Tri-O-alkylation of (III) in the presence of Cs2CO3 leads to the formation of partial-cone conformer tri-O-alkyl derivatives in quantitative yield. Ring inversion by oxygen-throughthe-annulus rotation takes place for the triethoxy derivative, but is inhibited for the tripropoxy and tributoxy derivatives. -(YAMATO, T.; DOAMEKPOR, L. K.; KOIZUMI, K.; KISHI, K.; HARAGUCHI, M.; TASHIRO, M.; Liebigs Ann.