The Synthesis of 2-Alkylated Cyclopentene-1,3-diones: Novel Compounds with Olfactory Properties

Abstract

The syntheses of 2-butyl-4,5-dimethylcyclopent-4-ene-1,3-dione, possessing a buttery jasmine odor, and a series of analogues have been carried out via the synthesis of butenolactones, with subsequent conversion to 4,5-dimethylcyclopent-4-ene-1,3-dione and an alkylation strategy. The compound with the strongest odor characteristics, has also been synthesised using a Pauson–Khand reaction and selective oxidative route.

Keywords:

• Butenolactones
• Cyclopentene-1,3-diones
• Pauson-Khand

Acknowledgments

We thank Bush Boake Allen for a studentship (MHJ), John Janes for helpful discussions, and Dirk Uwe Hahn. The ULIRS Mass Spectrometry Facility at the University of London School of Pharmacy are acknowledged for high resolution mass spectra.