Silole allylic anions instead of silanides

Reaction of a 3,4-diphenylsilole with two neopentasilanyl groups attached to the 2- and 5-positions with one equivalent of KO t Bu did not result in the expected silanide formation but yielded a silole allylic anion instead. The initially formed silanide added to a neighboring phenyl group, which then transfers a proton to the 2-position of the silole ring. The reactions of 3,4-diphenylsiloles with two neopentasilanyl groups in 2- and 5-positions with one equivalent of KO t Bu do not yield the expected silanides but silole allylic anions instead.