A Short Bi=Bi Bond Supported by a Metalloid Group 13 Ligand

摘要

Multiple bonds between main-group metals have brought much attention for more than the last two decades owing to both inherent fundamental chemistry and applications in synthesis. Particularly the isolation and structural characterization of multiply bonded Group 15 elements has posed a challenge to synthetic chemists. The first structurally characterized compound with a bismuth-bismuth double bond was discovered by Tokitoh et al. in 1997; it was prepared by treating sterically crowded tbtBiCl2 (tbt = 2,4,6-[(Me3Si)2CH]3C6H2) with Li2Se and subsequent reduction of resulting (tbtBiSe)3 with three equivalents of (Me2N)3P. Subsequently, it was shown that RBi=BiR (R = 2,6-(2,4,6-Me3C6H2)2C6H3 or bbt, 4-(SiMe3)3C-2,6-[(Me3Si)2CH]2C6H2) can also be obtained by the controlled reduction of the corresponding monoorganyl bismuth dihalides with magne-sium.