Metallole

Metalloles are metallacycle derivatives of cyclopentadiene in which the carbon atom at position 5, the saturated carbon, is replaced by a heteroatom.^[1] In contrast to its parent compound, the numbering of the metallole starts at the heteroatom. Some of these compounds are described as organometallic compounds, but in the list below quite a number of metalloids are present too. Some metalloles are fluorescent.^[2] Polymeric derivatives of pyrrole and thiophene are of interest in molecular electronics. Metalloles, which can also be viewed as structural analogs of pyrrole, include:

• Arsole, a moderately-aromatic arsenic analog
• Bismole, a bismuth analog
• Borole, a boron analog
• Furan (oxole), an oxygen analog
• Gallole, a gallium analog
• Germole, a germanium analog
• Phosphole, a phosphorus analog
• Pyrrole (azole), a nitrogen analog
• Selenophene, a selenium analog
• Silole, a silicon analog
• Stannole, a tin analog
• Stibole, an antimony analog
• Tellurophene, a tellurium analog
• Plumbole,^[4][5] a lead analog
• Thiophene, a sulfur analog
• Titanacyclopentadiene, e.g. (C₅H₅)₂TiC₄Ph₄^[6]
• Zirconacyclopentadiene, e.g. (C₅H₅)₂ZrC₄Ph₄^[7]
• Ferrole, an iron analog