Benzopyran


Benzopyran
Benzopyran
Identifiers
ChemSpider 10651828 YesY
Properties
Molecular formula C9H7O
Molar mass 131.15 g mol−1
Exact mass 131.049689846 g mol-1
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Benzopyran is an polycyclic organic compound that results from the fusion of a benzene ring to a heterocyclic pyran ring. According to IUPAC nomenclature it is called chromene. There are two isomers of benzopyran depending on the orientation of the fusion of the two rings, resulting in 1-benzopyran (chromene) and 2-benzopyran (isochromene). Due to a single unpaired electron, benzopyran has is found to be paramagnetic. The unpaired electron is delocalized over the whole benzopyran molecule, rendering it less reactive than one would expect otherwise, a similar example is cyclopentadienyl. Commonly, benzopyran is encountered in the reduced state, where it is partially saturated with one hydrogen. This reduced state has four structural isomers depending on where the hydrogen is attacking:

2H-Chromene
4H-Chromene
5H-Chromene
7H-Chromene
8aH-Chromene

See also

References