2-Undecanone, also known as methyl nonyl ketone and IBI-246, is the organic compound with the formula CH3C(O)C9H19.
It is usually produced synthetically, but it can also be extracted from various plant sources, including from essential oil of rue.
It is found naturally in bananas, cloves, ginger, guava, strawberries, wild-grown tomatoes, and the perennial leaf vegetable Houttuynia cordata.
Typically, 1–2% concentrations of 2-undecanone are found in dog and cat repellents in the form of a liquid, aerosol spray, or gel.
Like most methyl ketones, 2-undecanone undergoes a haloform reaction when in the presence of a basic solution of hypochlorite.