Fluorophenylantimony carboxylates. 1. Synthesis and spectroscopic (UV, IR,H-1 and F-19 NMR) studies of some new monofluoro- and pentafluorophenylantimony(III and V) derivatives of 2-methoxybenzoic acid

A series of new mono- and pentafluorophenylantimony(III and V) arylcarboxyl ates of the type ArnSb(OOCC6H4OCH3-2)(3-n) and Ar3Sb(OOCC6H4OCH3-2)(2) (Ar = p-FC6H4-, m-FC6H4- and C6F5-, n =1 or 2) have been synthesized by the rea ction of fluorophenylantimony (III or V) chlorides and the sodium salt of 2 -methoxybenzoic acid in the presence of 15-crown-5 as phase transfer cataly st. A representative compound, namely trimethylantimony(V) bis(2-methoxyben zoate) has also been synthesized for the sake of spectral comparisons. The van't Hoff factor 'i' and molar conductance data of the compounds revealed them to be monomeric and non-conducting in nature. The compounds were chara cterised by the usual physicochemical techniques e.g., elemental analyses, UV, IR and NMR (H-1, C-13 and F-19). Compound (III-VIII) are tentatively as signed as a trigonal bipyramidal structure in which the 2-methoxybenzoate a cted as monodentate ligand.