Bicyclopropylidene smoothly undergoes 1,3-dipolar cycloadditions to nitrones or nitrile oxides under different reaction conditions. The strained bisspirocyclopropanated isoxazolidines obtained from nitrones easily rearrange upon heating with selective opening of one of the two spirofused cyclopropane rings. This process produces 4-pyridone, 7-indolizinone, and 2-quinolizinone derivatives containing a spirocyclopropane moiety in the R-position to the carbonyl group in good yields. The same sequence of cycloaddition and rearrangement can be achieved in a “one-pot” operation with considerable benefit for the reaction yield. Bisspirocyclopropaneisoxazolines obtained from nitrile oxides are more stable than their saturated counterparts and rearrange only at higher temperature less chemoselectively. Opening of both spiro-fused cyclopropyl rings followed by aromatization produces interesting 2-substituted dihydrofuro[2,3-c]pyridine derivatives.

Thermal Rearrangement of Nitrone and Nitrile Oxide Cycloadducts to Bicyclopropylidene. Synthesis of 3-Spirocyclopropane-4-pyridone and Furo[2,3-c]pyridine Derivatives / A. Goti; B. Anichini; A. Brandi; S. I. Kozhushkov; C. Gratkowski ; A. de Meijere. - In: JOURNAL OF ORGANIC CHEMISTRY. - ISSN 0022-3263. - STAMPA. - 61:(1996), pp. 1665-1672.

Thermal Rearrangement of Nitrone and Nitrile Oxide Cycloadducts to Bicyclopropylidene. Synthesis of 3-Spirocyclopropane-4-pyridone and Furo[2,3-c]pyridine Derivatives

GOTI, ANDREA;ANICHINI, BEATRICE;BRANDI, ALBERTO;
1996

Abstract

Bicyclopropylidene smoothly undergoes 1,3-dipolar cycloadditions to nitrones or nitrile oxides under different reaction conditions. The strained bisspirocyclopropanated isoxazolidines obtained from nitrones easily rearrange upon heating with selective opening of one of the two spirofused cyclopropane rings. This process produces 4-pyridone, 7-indolizinone, and 2-quinolizinone derivatives containing a spirocyclopropane moiety in the R-position to the carbonyl group in good yields. The same sequence of cycloaddition and rearrangement can be achieved in a “one-pot” operation with considerable benefit for the reaction yield. Bisspirocyclopropaneisoxazolines obtained from nitrile oxides are more stable than their saturated counterparts and rearrange only at higher temperature less chemoselectively. Opening of both spiro-fused cyclopropyl rings followed by aromatization produces interesting 2-substituted dihydrofuro[2,3-c]pyridine derivatives.
1996
61
1665
1672
A. Goti; B. Anichini; A. Brandi; S. I. Kozhushkov; C. Gratkowski ; A. de Meijere
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificatore per citare o creare un link a questa risorsa: https://hdl.handle.net/2158/308423
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact