| Abstract [eng] |
The main goal of the work was to synthesize pyrrolo[2,3-d]pyrimidine-core based oligoarylenes with ethynyl and 1,2,3-triazole linkers and to evaluate their photophysical properties. Novel chromophores - 2,4-bis(4-aryl-1,2,3-triazol-1-yl)pyrrolo[2,3-d]pyrimidines were prepared by CuAAC reaction. It was demonstrated that in the CuAAC reaction of 2,4-diazidopyrrolo[2,3-d]pyrimidine along with 1,4-disubstituted 1,2,3-triazoles some amounts of 1,5-disubstituted isomers were formed. The synthesized 2,4-bis(4-aryl-1,2,3-triazol-1-yl)pyrrolopyrimidines exhibit efficient fluorescence in the range from 402 nm to 650 nm. A comparative study of Sonogashira and Stille reactions as well as Suzuki and Stille reactions for the introduction of alkynyl and aryl moieties onto pyrrolo[2,3-d]pyrimidine has been carried out. The synthesis of pyrrolo[2,3-d]pyrimidine oligoarylenes bearing different alkynyl and aryl substituents can be accomplished by applying two-step processes: Sonogashira – Stille or Stille – Stille. Likewise, 2,4-bis(arylethynyl)-7-methyl-7H-pyrrolo[2,3-d]pyrimidines bearing the same substituents can be obtained by one step Stille coupling starting from 2,4-dichloro-7-methyl-7H-pyrrolo[2,3-d]pyrimidine. Pd(PPh3)2Cl2/AsPPh3 has emerged as suitable catalyst system for Stille alkynylation and arylation reactions providing the desired products in good yields. The developed protocol allows a wide library of novel 2-aryl-4-(arylethynyl)pyrrolo[2,3-d]pyrimidines and 2,4-bis(arylethynyl)pyrrolo[2,3-d]pyrimidines to be generated, including those with different arylethynyl groups in positions 2 and 4 of the heterocycle. |
