Synthesis and structures of polychalcogenadistannabicyclo[k.l.m]alkanes

Reaction of steric encumbered trichlorostannane with disodium sulfide or dilithium selenide gave 2,4-dimercapto-1,3,2,4-dithiadistannetane or tetraselenadistannabicyclo[2.1.1]hexane, respectively. Reactions of steric encumbered trihydrostannane with elemental chalcogens gave pentachalcogenadistannabicyclo[k.1.1]heptanes (k = 2 and 3). The two bridgehead tin atoms of the first polychalcogenadistannabicyclo[k.l.m]alkanes are concluded to have no significant bonding interaction, judging from the longer bond distances than those of the normal tin-tin single bonds.