The insertion of chalcogen atoms into Al-Al and Ga-Ga bonds: Monomeric compounds with Al-Se-Al, Ga-S-Ga and Ga-Se-Ga groups

The insertion of chalcogen atoms into the element-element bonds of tetrakis[bis(trimethylsilyl)methyl]dialane(4) (1) and digallane(4) (2) by the reaction with the chalcogen atom donors triethyl phosphonium sulfide and selenide yields homoleptic compounds with novel R(2)Al--Se--AlR(2) (3), R(2)Ca--S--GaR(2) (4) and R(2)Ga-Se-GaR(2) groups (5). All products are monomeric both in solution and in the solid state, as shown by the cryoscopically determined molar masses and crystal structure determinations. The element-chalcogen-element bridges are bent and exhibit angles of 114.71 (3), 117.04 (4) and 113.45 degrees (5). Copyright (C) 1996 Elsevier Science Ltd