Patent ID: 7932418

Claim:
A process for the preparation of a compound of formula (I) wherein: the dotted lines indicate that the compound is in the form of a mixture of the corresponding β-γ or α-β unsaturated derivatives, the molar ratio β-γ/α-β being at least 3; Y represents a OR 4 or R 4 group, R 4 representing a C 1 -C 8 hydrocarbon group, optionally comprising 1 to 3 heteroatoms selected from the group consisting of oxygen, sulfur and nitrogen; R 1 represents a C 1 -C 15 hydrocarbon group, optionally comprising 1 to 3 heteroatoms selected from the group consisting of oxygen, sulfur and nitrogen; R 2 represents a C 1 -C 5 hydrocarbon group, optionally comprising 1 to 3 heteroatoms selected from the group consisting of oxygen, sulfur and nitrogen; and R 3 represents a hydrogen atom or a C 1 -C 5 hydrocarbon group; optionally wherein R 1 and R 2 , or R 1 and R 3 , taken together, form a C 4 -C 12 hydrocarbon group optionally comprising 1 to 3 heteroatoms selected from the group consisting of oxygen, sulfur and nitrogen; by a method which comprises: reacting, at a temperature between 100° C. and 230° C., a compound of formula wherein Y, R 1 , R 2 and R 3 are defined as in formula (I); with at least one compound from the group i) and at least one compound from the group ii) to prepare the compound of formula I, wherein: group i) is selected from the group consisting of salts of formula MX 2 and M″X 3 , wherein M is an alkali-earth cation and M″ is a lanthanide cation, and X is a halide or an anion of an acid HX having a pK a value between 0 and 6; and group ii) is a carboxylic acid of formula R 5 COOH, wherein R 5 represents a C 1 -C 18 hydrocarbon group optionally comprising one or two oxygen atoms; and wherein the reaction is optionally conducted in the presence of a polar aprotic solvent having a boiling point of above 100° C.