Synthesis, Structure, and Reactivity of Ga-Substituted Distibenes and Sb-Analogues of Bicyclo[1.1.0]butane.

Monovalent gallanediyl LGa {L=HC[C(Me)N(2,6-iPr2 C6 H3 )]2 } reacts with SbX3 to form the Ga-substituted distibenes [(LGaX)2 Sb2 ] (X=NMeEt 1, Cl 2). Upon heating, 2 reacts to the bicyclo[1.1.0]butane analogue [(LGaCl)2 (μ,η1:1 -Sb4 )] 3 containing a [Sb4 ]2- dianion. Moreover, 2 reacts with Li amides LiNR2 in salt elimination reactions that form the corresponding amido-substituted compounds 1 and [(LGaNMe2 )2 Sb2 ] 4, whereas reactions of 4 and [(LGaNMe2 )2 (μ,η1:1 -Sb4 )] 5 with two equivalents of GaCl3 resulted in the formation of 2 and 3, respectively. 1, 2 and 3 were characterized by 1 H and 13 C NMR spectroscopy, elemental analysis, and single crystal X-ray diffraction. In addition, their bonding situation was analyzed by quantum chemical calculations.