Unexpected product formed by the reaction of [2,6-(MeOCH2)2C6H3]Li with SbCl3: Structure of Sb–O intramolecularly coordinated organoantimony cation

Reaction of [2,6-(MeOCH2)2C6H3]Li (1) with SbCl3 in 1:1 molar ratio yielded except the intended product [2,6-(MeOCH2)2C6H3]SbCl2 (2) unexpected complex 3 consisting of antimony anion [Sb6Cl22]4− compensated by four intramolecularly coordinated organoantimony cations [2,6-(MeOCH2)2C6H3]2Sb+. Compound 3 is labile in CH2Cl2(CHCl3) solution and decomposes to compound 2 and SbCl3. Both compounds were characterized by the help of 1H and 13C NMR spectroscopy, ESI-mass spectrometry and in the case of 3 by single crystal X-ray diffraction techniques.