Process for preparation of trans-chrysanthemates
AssigneeRoussel Ulcaf
InventorsAlain Krief, Laszlo Hevesi
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Abstract
A novel process for the preparation of alkyl esters of dl-trans chrysanthemic acid of the formula ##STR1## wherein R is alkyl of 1 to 6 carbon atoms comprising reacting in the presence of a strong base an alkyl 4-oxo-2E-butenoate of the formula ##STR2## with at least about 2 molar equivalents of a triphenyl isopropyl phosphonium halide which uses easily accessible starting materials.
Claims6
A process for the preparation of an ester of the formula ##STR4## wherein R is alkyl of 1 to 6 carbon atoms comprising reacting at least 2 molar equivalent of a triphenyl isopropyl phosphonium halide based on the 4-oxo-2E-butenoate with a strong base and reacting the resulting ylide with an alkyl 4-oxo-2E-butenoate of the formula ##STR5##
A process for preparation of methyl 2,2-dimethyl-3RS-(2'-methyl-1'-propenyl)-cyclopropane-1RS-carboxylate comprising reacting methyl 4-oxo-2-butenoate with 3 molar equivalents of triphenyl isopropyl phosphonium iodide in an organic solvent in the presence of n-butyllithium.
Dependencies are inferred from the claim text.