Lanthanide(III) and group 13 metal ion complexes of tripodal amino phosphinate ligands

The tripodal amino-phosphinate ligands, tris(4-(phenylphosphinato)-3-benzyl-3-azabutyl) amine (H(3)ppba center dot 2HCl center dot H2O) and tris(4-(phenylphosphinato)-3-azabutyl) amine (H(3)ppa center dot HCl center dot H2O) were synthesized and reacted with Al3+, Ga3+, In3+ and the lanthanides (Ln(3+)). At 2 : 1 H(3)ppba to metal ratios, complexes of the type [M(H(3)ppba)(2)](3+) (M = Al3+, Ga3+, In3+, Ho3+-Lu3+) were isolated. The bicapped [Ga(H(3)ppba)(2)](NO3)(2)Cl center dot 3CH(3)OH was structurally characterized and was shown indirectly by various techniques to be isostructural with the other [M(H(3)ppba)(2)](3+) complexes. Also, at 2:1 H(3)ppba to metal ratios, complexes of the type [M(H(4)ppba)(2)](5+) (M = La3+-Tb3+) were characterized, and the X-ray structure of [Gd(H(4)ppba)(2)](NO3)(4)Cl center dot 3CH(3)OH was determined. At 1:1 H(3)ppba to metal ratios, complexes of the type [M(H(4)ppba)](4+) (M = La3+-Er3+) were isolated and characterized. Elemental analysis and spectroscopic evidence supported the formation of a 1:1 monocapped complex. Reaction of 1:1 ratios of H(3)ppa with Ln(3+) and In3+ yielded complexes of the type [M(H(3)ppa)](3+) (M = La3+-Yb3+) but with Ga3+, complex of the type [Ga(ppa)]center dot 3H(2)O was obtained. Reaction of 1:1 ratios of H(3)ppa with Ln(3+) and In3+ yielded complexes of the type [M(H(3)ppa)](3+) (M = La3+-Yb3+) but with Ga3+ a neutral complex [Ga(ppa)]center dot 3H(2)O was obtained. The formation of an encapsulated 1:1 complex is supported by elemental analysis and spectroscopic evidence.