Reaction pathways towards 1,1,2,2-tetratbutyldistannanes

1,2-Dichlorotetratbutyldistannane (1) is synthesized as a byproduct in the reaction of tbutylmagnesium chloride with tin tetrachloride or by the reaction of ditbutyltindihydride with ditbutyltin dichloride in the presence of amines. Reaction of 1 with lithium aluminumhydride yielded the dihydrido derivative 2. The treatment of 2 with bromoform gave the dibromo distannane 3 nearly quantitatively. Reactions of 2 with one equivalent of LDA or KH yielded unsymmetrically substituted alkali metal distannanes of the type MtBu2SnSn(H)tBu2 (4, M=Li; 5, M=K). Reaction of either two equivalents of KH with 2, or one equivalent of KH with 5 gave the dipotassium distannide 6. The molecular structure of the dichloro derivative 1 was determined by X-ray diffraction.