DESELENATION OF OVERCROWDED TRISELENANE DERIVATIVES CONTAINING BISMUTH - SYNTHESIS AND STRUCTURE OF THE FIRST STABLE DIBISMUTHENE

Deselenation of an overcrowded triselenatribismane, hylsilyl)methyl]ph enyl}-1,3,5-triselenatribismane, with hexamethylphosphorous triamide r esulted in the formation of the first stable dibismuthene {TbtBi=BiTbt ; Tot = 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl}, i.e. the doubly bonded compound consisting of the heaviest stable element in the perio dic table, as deep purple crystals. X-ray crystallographic structural analysis, UV-vis and Raman spectra, and the theoretical calculations r evealed the unique bonding character of the unprecedented Bi-Bi double bond.