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The synthesis and characterization of hexanuclear, octanuclear, and decanuclear manganese metalladiazamacrocycles of a series of pentadentate ligands with systematically controlled beta-branched N-acylsalicylhydrazides and alpha-branched N-acylsalicylhydrazides are reported. The results show that the size and shape of the substituents influence the nuclearity and the features of metalladiazamacrocycles because close contacts are occurring between the N-acyl substituents.

A manganese ion and a ditopic pentadentate ligand were used to self-assemble either an [S.sub.8] symmetrical 48-membered hexadecanuclear or an [S.sub.10] symmetrical 60-memebred icosanuclear manganese metallamacrocycle. The icosanuclear manganese metallamacrocycle was observed to have a remarkable toroidlike shape with a relatively large internal hydrophobic cavity and hence could be considered as a new donut-shaped host to accommodate small organic molecules.

The preparation of discrete metal-organic polyhedra (MOP) with nanosized cavities by combining triangular C3-symmetric facial ligands and a potential hexatopic Cu(II) ion is discussed. Findings reveal that the nitrate anion results in 2-fold interpenetrating MOFs with an augmented primitive 3-D cubic network topology.

A study reports the synthesis of a new [S.sub.4]-symmetric icosanuclear manganese metalladiazamacrocycle using a pentadentate ligand, N-3-phenyl-trans-2-propenoylsalicylhydrazide ([H.sub.3]L), that has a rigid and bulky terminal N-acyl group. It is found that a 20 cyclic repeat of an -(Mn-N-N)-linkage results in a highly puckered diaza-bridged 60-membered icosanuclear metallamacrocycle.

Discrete metal-organic polyhedra (MOP) with nanosized cavities and/or clusters of MOP could be prepared when C3-symmetric facial ligands and a potential hexatopic Cu(II) ion are combined in the presence of perchlorate as a weak linker, while similar reaction conditions in the presence of a nitrate linker led to extended metal-organic frameworks made of MOP as supramolecular building blocks.