Metallole

Metalloles are derivatives of cyclopentadiene in which the carbon atom at position 5, the saturated carbon, is replaced by a heteroatom. 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. Many metalloles are fluorescent and are used in organic light-emitting diodes (OLEDs) and other applications. Metalloles, which can also be viewed as structural analogs of pyrrole, include:

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