Research In The Synthesis Of Heterocycles Containing Nitrogen Compounds Through Radical Reactions

Because of its unique biological activity, low toxicity, high systemic and easy for structural modification and other advantages, heterocyclic compounds containing nitrogen in the natural products or biologically active compounds occupies an important position. The research of their synthetic methods is significant for industrial and commercial field. Thus, the simple and highly efficient routes for theire synthesis are very desirable. The thesis describes the synthesis of heterocyclic compounds via radical tandem reactions under metal-free conditions or silver-catalyzed radical decarboxylic reactions.1) Alkyl radical involved in the synthesis of quinolinones compoundsCinnamamide were studied as substrates, K₂S₂O₈ as oxidant, the reaction proceeded with pentane-2,4-dione to produce 3,4-dihydro quinolinones via radical tandem reactions under metal-free conditions. On the base of the result, we also studied the synthesis of 4-arylquinolinones under metal-free conditions using NaI/Selectfluor as catalytic system, after iodine cyclization, eliminating two step reaction got 4-arylquinolinones. All the compounds were characterized by ¹H NMR、¹³C NMR、HRMS spectra.2) The synthesis of the compounds of pyrimidines via radical reactionAgNO₃ as catalyst, aliphatic carboxylic acids or α-ketoacids as radical sources, 2-chloropyrimidine as substrate, we studied their reaction using K₂S₂O₈ as oxidant, many 4-substituted pyrimidines were obtained in aqueous solution via radical tandem reactions. All the compounds were characterized by ¹H NMR、¹³C NMR、HRMS spectra.3) The synthesis of oxindoles containing fluorine atom via radical tandem cyclization.N-methyl-N-phenylacrylamide and halogenated hydrocarbons containing fluorine atom were investigated as substrates, the reaction proceeded by the assistance of the simple BASF to produce the oxindoles. All the compounds were characterized by ¹H NMR、¹³C NMR、HRMS spectra.