Triorganoantimony(V) carboxylates: Synthesis, characterization and crystal structure of [Me3Sb(O2C–C5H4N)2] · H2O

Reactions of [R3Sb(OPri)2] with N-heterocylic carboxylic acids gave compounds of the type [R3Sb(O2C–Ar)2] (1) (R = Me, Et, Pri, Ph; Ar = 2-C5H4N, 2-C9H6N). The mono-bromo compound [Me3Sb(Br)(O2C–C5H4N)] (2) exists in equilibrium with [Me3Sb(O2C–C5H4N)2] and [Me3SbBr2]. All new compounds have been characterized by IR and NMR (1H and 13C{1H}) spectral data. X-ray structural analysis of one example, [Me3Sb(O2C–C5H4N)2], isolated as its monohydrate, revealed an essentially trigonal bipyramidal geometry for the antimony atom defined by three equilaterally disposed methyl groups and two oxygen atoms from monodentate carboxylate groups, in apical positions. The crystal structure is consolidated into a three-dimensional network by cooperative O–H⋯O, O–H⋯N and C–H⋯O interactions.

Graphical abstractTriorganoantimony carboxylates of the type [R3Sb(O2C–Ar)2] (1) (R = Me, Et, Pri, Ph; Ar = 2-C5H4N, 2-C9H6N) have been obtained by the reactions of [R3Sb(OPri)2] with N-heterocylic carboxylic acids. The mono-bromo compound [Me3Sb(Br)(O2C–C5H4N)] (2) exists in equilibrium with [Me3Sb(O2C–C5H4N)2] and [Me3SbBr2]. These compounds have been characterized by IR and NMR (1H and 13C{1H}) spectral data. X-ray structural analysis of one example, [Me3Sb(O2C–C5H4N)2], isolated as its monohydrate, revealed an essentially trigonal bipyramidal geometry for the antimony atom.Figure optionsDownload full-size imageDownload as PowerPoint slide