title: Rational design of the first closed coordination capsule with octahedral outer shape.
abstract: The rational synthesis of an octahedral coordination capsule in which the triangular faces are covered by single ligands is described herein. Starting with tris(2-hydroxybenzylidene)triaminoguanidinium chloride [H(6)L]Cl, we observed an oxidative cyclization of this ligand in the presence of PPh(4) (+) ions resulting in the complex [Pd(H(2)L')(PPh(3))] (1). The use of 5,5-diethylbarbiturate (bar(2-)) as a bridging ligand in the presence of [Co(en)(3)](3+) (en=ethylenediamine) leads to the formation of a rectangular box with the formula (Et(4)N)(6)[[Co[(PdCl)(Pd)L](2)(mu-bar)](2)] (2). The analysis of the architecture of compounds 1 and 2 enables the development of a self-assembly strategy for the synthesis of an octahedral coordination cage 3 with the formula Na(4)(Et(3)NH)(12)[(Pd(3)L)(8)[mu-(bar)](12)].x H(2)O. Compound 3 was characterized by (13)C-MAS-NMR spectroscopy and single-crystal structure analysis.
authors.affiliation: Lehrstuhl für Analytische Chemie, NC 4/27, Ruhr-University Bochum, 44780 Bochum, Germany. iris.m.mueller@rub.de
authors.forename: Iris M
authors.initials: IM
authors.lastname: Müller
authors.forename: Susanne
authors.initials: S
authors.lastname: Spillmann
authors.forename: Holger
authors.initials: H
authors.lastname: Franck
authors.forename: Rudolf
authors.initials: R
authors.lastname: Pietschnig