NEW NMR METHODS FOR THE STUDY OF FLEXIBLE ORGANIC-MOLECULES IN SOLUTION - APPLICATION TO THE CONFORMATIONAL STUDY OF SYMMETRICALLY SUBSTITUTED CALIX[6]ARENES IN SOLUTION

The study of flexible calix[6]arenes in solution has been largely overlooked because of the difficulties arising from their complex structures and flexibility. The combined use of several 2D-NMR techniques at low temperature with partial deuteration of the phenolic protons has allowed us the determination of the three dimensional structure of several calix[6]arenes in solution. The methodology that we have published has been extended with new NMR experiments that allow the study of molecules with greater flexibility.