Masking of Lewis acidity trends in the solid-state structures of trichlorido- and tribromido(2,2′:6′,2′′-terpyridine-κ3N,N′,N′′)gallium(III)

Abstract

The molecular structures of trichlorido(2,2′:6′,2′′-terpyridine-κ3N,N′,N′′)gallium(III), [GaCl3(C15H11N3)], and tribromido(2,2′:6′,2′′-terpyridine-κ3N,N′,N′′)gallium(III), [GaBr3(C15H11N3)], are isostructural, with the GaIIIatom displaying an octahedral geometry. It is shown that the Ga—N distances in the two complexes are the same within experimental error, in contrast to expected bond lengthening in the bromide complex due to the lower Lewis acidity of GaBr3. Thus, masking of the Lewis acidity trends in the solid state is observed not only for complexes of group 13 metal halides with monodentate ligands but for complexes with the polydentate 2,2′:6′,2′′-terpyridine donor as well.