Hexaaqua-aluminium(III) tris-(methane-sulfonate).

ABSTRACT: The title compound, [Al(H(2)O)(6)](CH(3)SO(3))(3) (common name: aluminium methane-sulfonate hexa-hydrate), was crystallized from an aqueous solution prepared by the precipitation reaction of aluminium sulfate and barium methane-sulfonate. Its crystal structure is the first of the boron group methane-sulfonates to be determined. The characteristic building block is a centrosymmetric unit containing two hexa-aqua-aluminium cations that are connected to each other by two O atoms of the -SO(3) groups in an O-H?O?H-O sequence. Further O-H?O hydrogen bonding links these blocks in orthogonal directions - along [010] forming a double chain array, along [10-1] forming a layered arrangement of parallel chains and along [101] forming a three-dimensional network. As indicated by the O?O distances of 2.600?(3)-2.715?(3)?Å, the hydrogen bonds are from medium-strong to strong. A further structural feature is the arrangement of two and four methyl groups, respectively, establishing 'hydro-phobic islands' of different size, all positioned in a layer-like region perpendicular to [101]. The only other building block within this region is one of the -SO(3) groups giving a local connection between the hydro-philic structural regions on both sides of the 'hydro-phobic' one. Thermal analysis indicates that a stepwise dehydration process starts at about 413?K and proceeds via the respective penta- and dihydrate until the compound completely decomposes at about 688?K.

SUBMITTER: Trella T 

PROVIDER: S-EPMC3414175 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature