A process for preparing a compound of formula by reaction between a compound of formula and a compound of formula in the presence of a copper-containing catalyst, a ligand and a base where: - R 1 is: - a hydrogen atom; - a straight-chain or branched alkyl group having 1 to 15 carbon atoms; - a straight-chain or branched alkenyl group having 1 to 15 carbon atoms and comprising at least one double bond; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - R 2 is: - a straight-chain or branched alkyl group having 1 to 15 carbon atoms: - a straight-chain or branched alkenyl group having 1 to 15 carbon atoms and comprising at least one double bond; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - R 3 is: - a substituted or unsubstituted vinyl group; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - X is a halogen atom selected from among fluorine, chlorine, bromine or iodine, a tosylate group or mesylate group. - R 1 is: - a hydrogen atom; - a straight-chain or branched alkyl group having 1 to 15 carbon atoms; - a straight-chain or branched alkenyl group having 1 to 15 carbon atoms and comprising at least one double bond; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - a hydrogen atom; - a straight-chain or branched alkyl group having 1 to 15 carbon atoms; - a straight-chain or branched alkenyl group having 1 to 15 carbon atoms and comprising at least one double bond; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - R 2 is: - a straight-chain or branched alkyl group having 1 to 15 carbon atoms: - a straight-chain or branched alkenyl group having 1 to 15 carbon atoms and comprising at least one double bond; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - a straight-chain or branched alkyl group having 1 to 15 carbon atoms: - a straight-chain or branched alkenyl group having 1 to 15 carbon atoms and comprising at least one double bond; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - R 3 is: - a substituted or unsubstituted vinyl group; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - a substituted or unsubstituted vinyl group; - a substituted or unsubstituted aryl group having 6 to 10 carbon atoms; - a substituted or unsubstituted heteroaryl group having 5 to 10 members including at least one heteroatom selected in particular from among a nitrogen atom or oxygen atom; - X is a halogen atom selected from among fluorine, chlorine, bromine or iodine, a tosylate group or mesylate group.