Syntheses and structures of lanthanoid(II) complexes featuring Sn-M (M = Al, Ga, In) bonds.

The reactions of the tris(pyridyl)tin(II) derivative [Li(thf)Sn(2-py(R))(3)] (py(R) = C(5)H(3)N-5-Me) (1) with the heavier group 13 alkyl compounds MEt(3), M = Ga or In, have been carried out. These led to formation of [{Li(thf)Sn(2-py(R))(3)}MEt(3)] adducts, which exhibit long Sn-M bonds and can be used for further lanthanoid metal coordination via the salt metathesis reaction with [Eu(Cp*)(2)(OEt(2))] (Cp* = η(5)-C(5)Me(5)) to give complexes [Eu{Sn(2-py(R))(3)MEt(3)}(2)]. In contrast, addition of the lighter group 13 analogue, (AlMe(3))(2), to 1 resulted in a pyridyl transfer reaction, yielding dimeric [AlMe(2)(2-py(R))](2). For comparison, the reaction of (AlMe(3))(2) with [Yb{Sn(2-py(R))(3)}(2)] (py(R) = C(5)H(3)N-3-Me) was explored, affording complex [Yb{Sn(2-py(R))(3)AlMe(3)}(2)]. All complexes have been characterised by NMR spectroscopy and X-ray crystallographic studies.