The amidinatoamidosilylene [LSiNMe2] [1; L = PhC(NtBu)2] was reacted with B2Br4(SMe2)2 in toluene at room temperature to form the bis(silylene)tetrabromodiborane [L{Me2N}Si]2B2Br4 (2). It was then reacted with excess KC8 in tetrahydrofuran at room temperature to afford the bis(silylene)dibromodiborene [L{Me2N}Si]2B2Br2 (3).