Process for the preparation of polymers containing benzohetero [1,3] diazole units

A process for the preparation of a polymer containing benzohetero[1,3]diazole units having general formula (I), (II), (III) or (IV):

• wherein:
• R1, R2, R3 and R6, the same or different from each other, represent a hydrogen atom;
• a linear or branched C1-C20 alkyl group;
• a linear or branched C1-C20 alkoxyl group;
• Y represents a penta- or hexa-atomic heteroarylene group, also benzo-condensed or heterobicyclic, containing from 1 to 4 heteroatoms selected from nitrogen, oxygen, sulfur, silicon, selenium, phosphorous;
• or Y represents an arylene group, said arylene group being optionally substituted with one or more —CR11 groups or with one or more —COR11 groups wherein R11 represents a hydrogen atom or a linear or branched C1-C20 alkyl group, or with one or more linear or branched C1-C20 alkyl groups, or with one or more aryl groups;
• W represents an oxygen atom;
• a sulfur atom;
• an NR group wherein R represents a hydrogen atom, or a linear or branched C1-C20 alkyl group;
• Z represents a sulfur atom;
• an oxygen atom;
• a selenium atom;
• an NR group wherein R represents a hydrogen atom, or a linear or branched C1-C30 alkyl group;
• R4 and R5, the same or different from each other, represent a hydrogen atoms;
• a linear or branched C1-C20 alkyl group;
• a linear or branched C1-C20 alkoxyl group;
• or, when m is 0, R4 and R5 can be optionally bound to each other to form, together with the carbon atoms to which they are bound, a condensed cycle containing from 3 to 14 carbon atoms, saturated, unsaturated, or aromatic, optionally containing one or more heteroatoms, said condensed cycle being optionally substituted with one or more linear or branched C1-C20 alkyl groups, or with one or more linear or branched C1-C20 alkoxyl groups;
• R7 and R8, the same or different from each other, represent a hydrogen atom;
• a linear or branched C1-C20 alkyl group;
• a linear or branched C1-C20 alkoxyl group;
• a —CH2OR12 group wherein R12 represents a hydrogen atom, or a linear or branched C1-C20 alkyl group;
• or, R7 and R8 can be optionally bound to each other to form, together with the carbon atoms to which they are bound, a condensed cycle containing from 3 to 14 saturated, unsaturated or aromatic carbon atoms, optionally containing one or more heteroatoms, said condensed cycle being optionally substituted with one or more linear or branched C1-C20 alkyl groups, or with one or more linear or branched C1-C20 alkoxyl groups;
• R9 and R10, the same or different from each other, represent a hydrogen atom;
• a linear or branched C1-C20 alkyl group;
• a linear or branched C1-C20 alkoxyl group;
• m is 0, 1, or 2;
• n is an integer ranging from 10 to 500;
• said process comprising:
• reacting at least one disubstituted benzohetero[1,3]diazole compound having general formula (V):
• wherein X represents a halogen atom selected from chlorine, fluorine, bromine, iodine, and Z, R1 and R2, have the same meanings described above;
• with at least one heteroaryl compound having general formula (VI), (VII), (VIII) or (IX):
• wherein W, Y, R3, R4, R5, R6, R7, R8, R9 and R10, have the same meanings described above.