| 摘要 |
<p>The invention concerns cycloaliphatic ketones of formula (I) which have two conjugated double bonds in positions 1 and 3, or 2 and 4, as shown by the dashed lines, and in which formula R defines a C1-C3 alkyl radical. The cycloaliphatic ketones are used as intermediate products in the preparation of jasmonic derivatives and are obtained by an addition reaction between cyclopentanone and an aldehyde of formula (II) of which the double bond has the configuration (E) and in which R has the meaning given above, to provide a dienic cyclopentanone of formula (Ia) E,E. The resulting cyclopentanone is optionally subjected to a heat treatment to give a cyclopentenone of formula (Ib) Z. 2-(E,2'Z)-but-2'-enylidene-cyclopentanone, 2-(1'Z)-but-1'-enyl-cyclopent-2-enone, 2-(E,2'E)-pent-2'-enylidene-cyclopentanone, 2-(Z,2'E)-pent-2'-enylidene-cyclopentanone, 2-(1'Z)-pent-1'-enyl-cyclopent-2-enone, dimethyl [2-(pent-(1'Z)-enyl)-3-oxo-1-cyclopentyl]-malonate malonic esters and dimethyl [2-(but-(1'Z)-enyl)-3-oxo-1-cyclopentyl]-malonate malonic esters are novel chemical compounds.</p> |
