In recent years the chemistry of the materials for biomedical purpose is developing intensively. This is due to necessity to create of new generation of biocompatible composites for implants, effective drug delivery systems and substratum for tissue engineering. The various functional polymers that are suitable to immobilize and controlled release of synthetic medicinal substances, proteins, nucleic acids and other biopolymers under mild conditions are used for this purpose. The maleimide, attached to mineral base, is used for immobilization of the compounds with various strong nucleofilic centers such as thiol, amine and hydroxyl groups, etc.
Synthesis of maleimide based monomers-initiators, chain transfer agents for radical polymerization, maleimide fragment containing surfactants and bi-functional maleimide derivative with protected maleimide C=C bond will able to create a new approach to obtain functional oligomers with side- and end- maleimide fragment. The last mentioned are interesting as new biomedical application materials for reversible immobilization or modification of biomolecules.
The purpose of the work was obtaining novel N-4-isopropylbenzylic derivatives imides of dicarboxylic acids C4 for continuous utilization as reactants for obtaining novel functional monomers and initiators.
The reaction of dicarboxylic acids imides and p-chloromethylcumene with the participation of potassium carbonate indimethylformamide was used for obtaining of dicarboxylic cumeneimides. Previously method of alkylation was confirmed on the example of widely available succinimide. The reaction was carried out at 50 °C in dimethylformamide. Practically quantative conversion was achieved in 20 hours. Full conversion for maleimide was achieved in 4 hours. The higher reactivity of maleimide compared to succinimide is explained by fact that the N-alkylation of imide goes through the stage of the formation of the transitional salt of imide. The salt plays a role of nucleophile at this stage. The concentration of the potassium salt of maleimide in the reaction mixture is higher than salt of succinimide and the rate of alkylation as well because the acidity of maleimide is higher than acidity of succinimide.
As the result of the work the derivatives of imides of dicarboxylic acids containing cumene moiety were obtained. Isopropylbenzylmaleimide can be used as intermediate for synthesis of radical polymerization chain transfer agents. Structure of the compounds was confirmed by physical and chemical methods.
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