Synthesis and Structural Study of Organoantimony(III) and Organobismuth(III) Triflates and Cations Containing O,C,O-Pincer Type Ligands

The reactions of intramolecularly coordinated organoantimony and organobismuth dihalides L 1 SbCl 2 and L 2 BiCl 2, containing two types of O,C,O-pincer ligands 2,6-(ROCH 2 )C 6 H 3 - (L 1, R = Me; L 2, R = t Bu), with silver salts of the weakly nucleophilic polar groups CF 3 SO 3 - (OTf) and CB 11 H 12 - (in 1:1 and 1:2 molar ratios) gave the following compounds: L 1 SbCl(OTf) ( 1 ), L 2 BiCl(OTf) ( 2 ), L 1 Sb(OTf) 2 ( 3 ), L 2 Bi(OTf) 2 ( 4 ), L 1 SbCl(CB 11 H 12 ) ( 5 ), L 2 BiCl(CB 11 H 12 ) ( 6 ). All compounds were characterized structurally by X-ray diffraction. In the solid state, compounds 1 − 3 have OTf groups covalently (although weakly) bound to the central metal atom. In compound 4, one of the OTf groups is bound in a unidentate fashion and the other in a weakly chelating fashion. Compounds 5 and 6 exist as separated ion pairs consisting of a [L 1 SbCl(THF)] + or [L 2 BiCl] + cation and CB 11 H 12 - anion. The donor oxygen atoms are coordinated to the metal atoms through strong intramolecular interactions in all compounds. The solution structures of all compounds were studied by the help of variable-temperature 1 H NMR measurements.