Organooxotin cages, {[(n-BuSn)3(μ3-O)(OC6H 4-4-X)3]2[HPO3]4}, X = H, Cl, Br, and I, in double O-capped structures: Halogen-bonding-mediated supramolecular formation

Abstract

The reaction of n-BuSn(O)(OH) with H3PO3 and HOC 6H4-4-X (X = H, Cl, Br, and I) afforded the hexanuclear organooxotin cages {[(n-BuSn)3(μ3-O)(OC 6H4-4-X)3]2[HPO3] 4}, where X = H (1), Cl (2), Br (3), and I (4), in moderate yields. These cages possess double O-capped structures. The oxotin cages 1-4 contain two tritin motifs that are joined by four tripodal [HPO3]2- ligands. The three tin atoms in each tritin subunit are held together by a μ3-capping oxygen atom. In addition three phenolate oxygen atoms act as μ2-bridging ligands between two tin atoms. The molecular structures of 1-4 are intimately related to other organooxotin cages such as the O-capped cluster, the drum, and the football cage. The crystal structures of 2-4 reveal intermolecular halogen-bonding-mediated [X- - -O (X = Cl, Br), I- - -I, and I- - π] supramolecular assemblies. © 2005 American Chemical Society.