Synthesis and characterisation of asymmetrically bridged calix[4]arene and tetrathiacalix[4]arene mono amido crown derivatives.

The synthesis of asymmetrically bridged calix[4]arene and tetrathiacalix[4]arene amido crown derivatives has been achieved by the aminolysis of distal diester derivatives of calix[4]arene and tetrathiacalix[4]arene with 1,2-diaminopropane or 1,2-diaminocyclohexane (stereoisomeric mixture, mainly trans). The title compounds have been characterised by detailed analysis of their NMR spectra. The assignment of NMR signals and stereo differentiation in the amido crown ring formation has been studied using a chiral shift reagent. [ABSTRACT FROM AUTHOR]