Synthesis of tetrahemispheraplexes with ammonium, alkylammonium or alkaline metal ions as exohedral guests via self-assembly or guest exchange

Abstract

To study the interplay between the steric demand of the guest and the space available at the host, we have prepared the tetraammonium complexes {(NH4)(4)boolean AND[Mg-4(L-1/2)(6)]} 1, tetrakis(methylammonium) complexes {(Me-NH3)(4)boolean AND[Mg-4(L (1/2))(6)]} 2, tetrakis(ethylammonium) complex {(Et-NH3)(4)boolean AND[Mg-4(L-1)(6)]} 3, and mixed sodium tris(ethylammonium) complex {Na(Et-NH3)(3)boolean AND(Mg-4(L-2)(6)]} 4. The tetrahemispheraplexes 1-4 were available in one-pot syntheses. The tetrakis(alkylammonium) clusters {(R-1-NH3)(4)boolean AND[Mg-4(L-1)(6)]} 5 and the mixed diammonium-bis(p-methoxybenzylammonium) cluster {(NH4)(2)(R-2-NH3)(2)boolean AND[Mg-4(L-1)(6)]} 6, however, were prepared by exchange of the ammonium ions of la by alkylammonium ions, Similarly, exchange of the four ammonium ions of 1b by alkaline metal cations afforded the tetraalkaline metal tetrahemispheraplexes {M(4)boolean AND[Mg-4(L-2)(6)]} 7. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).