Reactivity of distibanes toward trialkylalanes and -gallanes: Syntheses and X-ray structures of bisadducts and heterocycles

Reactions between distibanes of the type Sb2R4 and trialkylalanes and -gall anes R ' M-3 in 1:2 stoichiometry yield eight bisadducts of the type [Sb2R4 ] [MR ' (3)](2) (R = Me, R ' = t-Bu, M = Al 1, Ga 2; R = Et, M = Al, R ' = Me 3, Et 4, t-Bu 5; M = Ga, R ' = Me 6, Et 7, t-Bu 8), which were character ized by multinuclear NMR studies and elemental analysis. In addition, 1, 2, 5, and 8 are the first structurally characterized neutral main group Lewis acid-distibane bisadducts. 1-8 are unstable in solution toward the formati on of heterocycles of the type [R2SbMR ' (2)](x). [Me2SbGa(t-Bu)(2)](3) (9) and [Et2SbGa(t-Bu)(2)](2) (10) have been isolated and their solid state st ructures determined by single-crystal X-ray diffraction.