Crystal structure of catena-poly[[aquadi-n-propyl­tin(IV)]-μ-oxalato]

The Sn^IV atom in the title compound shows a slightly distorted penta­gonal–bipyramidal SnC₂O₅ coordination with the C atoms of the aliphatic chain in the axial positions.

catena-Poly[[di-tert-butyl­tin(IV)]-μ-oxalato]

The title compound, [Sn(C₄H₉)₂(C₂O₄)]_n, an unexpected side product in the reaction of di-tert-butyl­tin(IV) oxide with nitric acid, represents the first diorganotin(IV) oxalate to be structurally characterized. The Sn^IV atom of the one-dimensional coordination polymer is located on a mirror plane and is coordinated by two chelating oxalate ions with two rather different Sn—O bond lengths of 2.150 (1) and 2.425 (1) Å, and two t-butyl groups with Sn—C bond lengths of 2.186 (2) and 2.190 (2) Å. The coordination polyhedron around the Sn^IV atom is a distorted tetra­gonal disphenoid. The centrosymmetric oxalate ion also has an asymmetric coordination geometry, as reflected by the two slightly different C—O bond lengths of 1.242 (2) and 1.269 (2) Å. The chains of the polymer propagate along the b-axis direction. Only van der Waals inter­actions are observed between the chains.

Methyl­phospho­nic acid, CH₃PO(OH)₂

The asymmetric unit of the title compound, CH₅O₃P, contains two independent mol­ecules with nearly identical bond lengths and angles. In the crystal, each of the mol­ecules acts as acceptor (P=O) and donor (P-OH) of four hydrogen bonds to three adjacent mol­ecules, resulting in the formation of two different bilayers (one for each mol­ecule) stacked perpendicular to the a axis in the crystal.