Methyl cyclopentenolone occurs in beechwood tar
and has a caramel-like (burnt sugar) odor. It has been identified as a flavor
component in food. Crystals of the compound usually contain 1 mol
of water. Synthetic routes of production are of limited importance in comparison
with isolation from beechwood tar. Homologs of cyclotene such as
3-ethyl-2-hydroxy-2-cyclopenten-1-one, C
7
H
10
O
2
, Mr 126.16,
2-hydroxy-3,4-dimethyl-2-cyclopenten-1-one, C
7
H
10
O
DryPowder|white, crystalline powder with a nutty odour, maple-liquorice aroma in dilute solution