[(Ethylenediamine)Pt(uracilate)]4, a Metal Analogue of Calix[4]arene. Coordination and Anion Host−Guest Chemistry Related to Its Conformational Dynamics

摘要: The open “molecular box” [(en)Pt(UH-N1,N3)]4(NO3)4 (with en = 1,2-diaminoethane, UH uracil monoanion) resembles calix[4]arenes in its structure and solution dynamics. It adopts a 1,3-alternate conformation the solid-state (1a), but after deprotonation to [(en)Pt(U-N1,N3)]4, second major species (cone conformer (1b-4H+)) occurs. 1b-4H+ acts as an efficient ligand for additional metal ions through oxo-surface formed by four O2 exocyclic atoms of nucleobases. As shown here, can incorporate single ion only, giving rise formation type {[(en)PtU]4M}(X)n with M ZnII (2a), BeII (3) (not isolated solid state), LaIII (4); X NO3, SO4/2; n 2, 3. In addition, both protonated cone (1b, pH 2−4) compounds 2a (at 3−8) 3 3−5) act hosts organic anions water, deduced from 1H NMR studies. is proposed that conformers anion due combination pos...