The synthesis and characterization of a family of novel alkaline earth metal stannides, in addition to tri-and pentastannanes are described.[Ba (18-crown-6)(HMPA) 2][SnPh3] 2 (4),[Ca (18-crown-6)(HMPA) 2][Sn (SnPh3) 3] 2 (5), and [Sr (18-crown-6)(HMPA) 2][Sn (SnPh3) 3] 2 (6) were synthesized by insertion of the corresponding alkaline earth metals into the tin tin bond of hexaphenyldistannane. Ph3SnSnPh2SnPh3 (7), and Sn (SnPh3) ...