Bismabenzene

Bismabenzene (C₅H₅Bi) is the parent representative of a group of organobismuth compounds that are related to benzene with a carbon atom replaced by a bismuth atom. Bismabenzene itself has been synthesised but not isolated because it is too reactive, tending to instead dimerize in a Diels-Alder addition.^[1][2][3]

Bond lengths and angles of benzene, pyridine, phosphorine, arsabenzene, stibabenzene, and bismabenzene^{[clarification needed]}

Bismabenzene

Names
Preferred IUPAC name Bismine
Other names Bismin
Identifiers
CAS Number	289-52-1
3D model (JSmol)	Interactive image
ChemSpider	119910
PubChem CID	136133
CompTox Dashboard (EPA)	DTXSID50183094
InChI InChI=1S/C5H5Bi/c1-2-4-6-5-3-1/h1-5H Key: ZEBPXYQZSWNMLH-UHFFFAOYSA-N
SMILES C1=CC=[Bi]C=C1
Properties
Chemical formula	C5H5Bi
Molar mass	274.075 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

An unstable derivative with 4-alkyl substituents was reported in 1982.^[4] A stable derivative, with two ortho tri(isopropyl)silyl substituents, was synthesized from aluminacyclohexadiene, bismuth trichloride, and DBU in 2016.^[1][5]