SIMULTANEOUS BINDING OF BORON AND AMMONIUM CATION BY A PSEUDOCRYPTAND- SYNTHESIS, X-RAY-ANALYSIS AND SOLUTION STUDIES BY NMR-SPECTROSCOPY

Treatment of the macrocyclic compound 1 bearing two catecholate moieti es with equimolar amounts of B(OH)(3) and aqueous NH3 in a H2O-EtOH mi xture gave exclusively the ammonium inclusion complex 2 which was then studied both in solution and in the solid state; the selectivity sequ ence NH4+ > Na+ > Cs+ in CD3OD solution was obtained and the ammonium ion complex 2 was found to be more stable than the ([222], NH4+) compl ex by at least 3 orders of magnitude.