Homo- and Heteroleptic 8-Quinaldinolate Complexes From Elevated-temperature Rearrangements
Three new zinc 8-quinaldinolate complexes have been obtained from rearrangement reactions at elevated temperatures including the first homoleptic zinc 8-quinaldinolate complex. The homoleptic, trinuclear complex [Zn3(MQ)6] (1) (MQ = 8-quinaldinolate) was obtained by the recrystallisation of amorphous Zn(MQ)2 from a 1,2,4,5-tetramethylbenzene flux at 270°C. The heteroleptic complexes [Zn4Cl4(MQ)4] (2) and [Zn4Cl2(MQ)6] (3) were simultaneously obtained by the reaction between Zn(MQ)2 and anhydrous ZnCl2 under the same conditions. All complexes contain quinaldinolate ligands in a mixed chelating–bridging coordination mode. The homoleptic complex adopts a V-shaped geometry whereas the heteroleptic complexes adopt closely related cyclic structures.