Patent ID: 7732541

Claim:
Process for preparing a polymer whose skeleton comprises a sequence of units of formula (I′): in which: R 1 represents a hydrogen atom or a hydrocarbon-based group chosen from linear or branched alkyl groups containing from 1 to 20 carbon atoms, cycloalkyl groups containing from 3 to 8 carbon atoms, alkoxy groups containing from 1 to 20 carbon atoms, aryl groups containing from 6 to 20 carbon atoms and aryloxy groups containing from 6 to 20 carbon atoms; R′ 2 represents a hydrogen or halogen atom or a hydrocarbon-based group chosen from linear or branched alkyl groups containing from 1 to 20 carbon atoms, cycloalkyl groups containing from 3 to 8 carbon atoms, alkoxy groups containing from 1 to 20 carbon atoms, aryl groups containing from 6 to 20 carbon atoms and aryloxy groups containing from 6 to 20 carbon atoms; the radicals R 3 and R 4 , which may be identical or different, correspond to the same definition as R 1 , on condition that at least one of the radicals R 3 and R 4 represents, in each unit, a hydrogen atom; the said radicals R 1 , R′ 2 , R 3 and R 4 possibly comprising, when they represent a hydrocarbon-based group, one or more substituents chosen from halogen groups, alkyl groups of 1 to 20 carbon atoms, alkoxy groups of 1 to 20 carbon atoms, aryl groups of 6 to 20 carbon atoms, aryloxy groups of 6 to 20 carbon atoms and amino groups, the said process comprising a step consisting in reacting, in suitable amount: at least one ylide compound corresponding to formula (2) below: in which the radicals R 1 , R′ 2 , R 3 and R 4 correspond to the same definition as that given above, E being a leaving group, with a trivalent boron compound, comprising at least one group capable of migrating, so as to obtain the said sequence of units of formula (I′) as defined above.