Bis[bis(trimethylsilyl)cyclopentadienyl]selane as a ligand: selena-2,2′,4,4′-tetrakis(trimethylsilyl)-[1]ferrocenophane and 1,2,3-triselena-2,2′,4,4′-tetrakis(trimethylsilyl)-[3]ferrocenophane

Bis[bis(trimethylsilyl)cyclopentadienyl]selane (1) was prepared from lithium 5,5-bis(trimethylsilyl)cyclopentadienide and selenium bis(diethyldithio)carbamate, Se(S2CNEt2)2. Reaction of the dianion of 1 with FeCl2 gave selena-2,2′,4,4′-tetrakis(trimethylsilyl)-[1]ferrocenophane (2) and 1,2,3-triselena-2,2′,4,4′-tetrakis(trimethylsilyl)-[3]ferrocenophane (3). Compounds 1–3 have been characterized by 1H-NMR, 13C-NMR and single-crystal X-ray analyses.