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Progress and problems in activated polycondensation

New polycondensation methods for the synthesis of polymers based on non-traditional ways of activating monomers are classified. For the sake of convenience and as a contrast to traditional low-temperature polycondensation, it has been proposed to combine the new methods under the general title of "activated polycondensation". It is shown that the most versatile method in terms of synthesis is that based on the activation of the "leaving" part of the biselectrophile — the "activated amide and ester method". The considerable future potential of the latter is demonstrated. Problems related to the synthesis, structure, and reactivity of different classes of activated diesters are examined. The possibility of synthesising various heterochain polymers by reaction of activated diesters with di- and poly-functional nucleophiles is demonstrated. The advantages of this method for the synthesis of polymers are established. The bibliography includes 145 references.