Facile syntheses of 3,4-disubstituted pyrroline nitroxides and their further synthetic applications

Györgyi Úr, T. Kalai, K. Hideg

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Lithiation of an α,β-unsaturated pyrroline nitroxide ester at the β-carbon with LTMP followed by treatment with electrophiles led to a new series of 3,4-disubstituted pyrroline nitroxides, which could be used as valuable paramagnetic building blocks. The new compounds were tested in Sonogashira and Stille cross coupling reactions, which offered methyl 1-oxyl-4-substituted-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-3-carboxylate radicals for new C-C bond formation in poor to moderate yields. The reaction of an α,β-unsaturated pyrroline nitroxide ester with methyl chloroformate generated diester 2b; the partial hydrolysis product of this reaction was shown to be a key compound for the synthesis of paramagnetic uracil derivative 10.

Original languageEnglish
Pages (from-to)778-780
Number of pages3
JournalTetrahedron Letters
Volume57
Issue number7
DOIs
Publication statusPublished - Feb 17 2016

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Esters
Uracil
Cross Reactions
Hydrolysis
Carbon
Derivatives
pyrroline
methyl chloroformate

Keywords

  • 2-Nitrobenzyl protecting group
  • Lithiation
  • Nitroxides
  • Pd-catalyzed cross coupling
  • Uracil

ASJC Scopus subject areas

  • Biochemistry
  • Organic Chemistry
  • Drug Discovery

Cite this

Facile syntheses of 3,4-disubstituted pyrroline nitroxides and their further synthetic applications. / Úr, Györgyi; Kalai, T.; Hideg, K.

In: Tetrahedron Letters, Vol. 57, No. 7, 17.02.2016, p. 778-780.

Research output: Contribution to journalArticle

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