Cyclopent-2-en-4-ol-l-one

The synthesis of this compound represents a notable departure from those discussed above. The presence of the carbonyl group at the 9 position of the cyclopentane ring, which classifies this compound as a PGE, removes one asymmetric center and thus somewhat reduces the stereochemical complexity of the synthesis. More importantly, this introduces the possibility of attaching the lower side chain by means of a 1,4-addition reaction the tram relationship of the two side chains should be favored by thermodynamic considerations. The very unusual functionality of the required Michael acceptor, that of a cyclopent-2-en-4-ol-l-one, leads to a rather lengthy albeit straightforward synthesis for the requisite intermediate. 

Titanium trichloride Cyclopent-2-enones from cyclopent-2-en-4-ol-l-ones... 

CIC The main components, responsible for the repulsive odour are 1-propanethiol, ethanthiol and methanethiol, and the corresponding sulfides. Ethyl butyrate and ethyl-2-methyl butyrate impart the fruity, fresh strawberry character. Components like vanillin, 2,5-dimethyl-4-hydroxy-furan-3(2H)-one, 3-methyl-cyclopent-2-en-2-ol-l-one, gamma-decalactone (all not yet identified in Durian) may support the creamy nutty character. 

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