Substituent effects in the 1,3‐dipolar cycloaddition reactions of 2‐methylenecephalosporins with diazoalkanes

János Pitlik, J. Csaba Jászberényi, István Komáromi

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The 2‐methylenecephalosporins 1 undergo stereoselective 1,3‐dipolar cycloaddition reactions with diazoalkanes to give exclusively the spirocyclopropylcephalosporins 3. Substituens at C‐3, C‐4 and C‐7 of the cephalosporin nucleus do not display a significant effect on the reactivity of the 2‐exo double bond. However, reduction of the sulfoxides to sulfides has an inactivating influence. Reactions with substituted diazoalkanes proceed more slowly in every case. The results are explained by theoretical (PM3, AM1 and MNDO) calculations.

Original languageEnglish
Pages (from-to)699-701
Number of pages3
JournalLiebigs Annalen der Chemie
Volume1991
Issue number7
DOIs
Publication statusPublished - 1991

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Sulfoxides
Cycloaddition Reaction
Sulfides
Cephalosporins

Keywords

  • 1,3‐Dipolar cycloaddition
  • Cephems, 2‐methylene‐, substituent effects
  • Diazoalkanes
  • Methylenecephems

ASJC Scopus subject areas

  • Medicine(all)

Cite this

Substituent effects in the 1,3‐dipolar cycloaddition reactions of 2‐methylenecephalosporins with diazoalkanes. / Pitlik, János; Csaba Jászberényi, J.; Komáromi, István.

In: Liebigs Annalen der Chemie, Vol. 1991, No. 7, 1991, p. 699-701.

Research output: Contribution to journalArticle

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