The reactions of the tris(pyridyl)tin(II) derivative [Li(thf)Sn(2-py^R)₃] (py^R = C₅H₃N-5-Me) (1) with the heavier group 13 alkyl compounds MEt₃, M = Ga or In, have been carried out. These led to formation of [{Li(thf)Sn(2-py^R)₃}MEt₃] 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(OEt₂)] (Cp* = η⁵-C₅Me₅) to give complexes [Eu{Sn(2-py^R)₃MEt₃}₂]. In contrast, addition of the lighter group 13 analogue, (AlMe₃)₂, to 1 resulted in a pyridyl transfer reaction, yielding dimeric [AlMe₂(2-py^R)]₂. For comparison, the reaction of (AlMe₃)₂ with [Yb{Sn(2-py^R)₃}₂] (py^R = C₅H₃N-3-Me) was explored, affording complex [Yb{Sn(2-py^R)₃AlMe₃}₂]. All complexes have been characterised by NMR spectroscopy and X-ray crystallographic studies.