Organoelement Complexes of a Dinucleating Double β-Diiminato Ligand - Precedent Cases from Groups 1, 2, and 13

Main group chemistry of dinucleating ligands based on a xanthene backbone and two parallel diiminato binding sites (Xanthdim) has been investigated. To complement studies concerning the coordination modes adopted by Xanthdim in combination with alkali metal ions a di‐rubidium complex with toluene co‐ligands has been prepared. Its structural parameters lie in between those previously observed for corresponding K+ and Cs+ complexes. Furthermore, the complexes [ Me 2C 6H 3Xanthdim](MgMe(thf))2 (2) and [ Me 2C 6H 3Xanthdim](MgBr(thf))2 (3) were synthesised by reaction of [ Me 2C 6H 3Xanthdim](K(thf)2)2 and [ Me 2C 6H 3Xanthdim]H2, respectively, with MeMgBr. Both compounds proved stable against ligand exchange according to the Schlenk equilibrium. After reaction of [ Me 2C 6H 3Xanthdim]H2 and [ F 2C 6H 3Xanthdim]H2, respectively, with AlMe3 the complexes [ Me 2C 6H 3Xanthdim](AlMe2)2 (4) and [ F 2C 6H 3Xanthdim](AlMe2)2 (5) were isolated and fully characterised. They were found to be dynamic in solution and Al–CH3···F‐aryl interactions were detected in case of 5. The solid‐state structures and NMR spectroscopic properties of all compounds were determined and analysed.