Tetrakis(mu2-4-aminobenzoato)di-mu3-oxido-tetrakis[dibutyltin(IV)]

The molecule of the title compound, [Sn(4)(C(4)H(9))(8)(C(7)H(6)NO(2))(4)O(2)], lies about an inversion centre and is a tetranuclear bis(tetrabutyldicarboxylatodistannoxane) complex containing a planar Sn(4)O(2) core in which two mu(3)-oxide O atoms connect an Sn(2)O(2) ring to two exocyclic Sn atoms. Each Sn atom has a highly distorted octahedral coordination. In the molecule, the carboxylate groups of two aminobenzoate ligands bridge the central and exocyclic Sn atoms, while two further aminobenzoate ligands have highly asymmetric bidentate chelation to the exocyclic Sn atoms plus long O...Sn interactions with the central Sn atoms. Each Sn atom is also coordinated by two pendant n-butyl ligands, which extend roughly perpendicular to the plane of the Sn(4)O(10) core. Only one of the four unique hydrogen-bond donor sites is involved in a classic N-H...O hydrogen bond, and the resulting supramolecular hydrogen-bonded structure is an extended two-dimensional network which lies parallel to the (100) plane and consists of a checkerboard pattern of four-connected molecular cores acting as nodes. The amine groups not involved in the hydrogen-bonding interactions have significant N-H...pi interactions with neighbouring aminobenzene rings.