The preparation and co-ordination chemistry of 2,2′ :6′,2″-terpyridine macrocycles. Part 3. Transient template effects involving dimethyltin(IV)

Abstract

Complexes of a novel quinquedentate ligand L1, which incorporates a 2,2′ :6′,2″-terpyridine moiety, are prepared via template condensations about nickel(II) or manganese(II). The crystal and molecular structure of [NiL1(EtOH)2][BF4]2 shows the metal to be in a pentagonal-bipyramidal N5O2 environment. The free ligand L1 may be obtained as its dication from template condensations in which there is a mismatch between the donor properties of the ligand and the acceptor properties of the metal ion. Thus [H2L1][PF6]2 may be isolated from the template condensation about Cr3+ or [SnMe2]2+. The crystal and molecular structure of [H2L1][PF6]2 is reported, and the origin of this novel template effect is discussed.