A crucial synthetic transformation employing 7-oxabicyclo[2.2.1]heptanes

March 04, 2024

• Title:       

  A crucial synthetic transformation employing 7-oxabicyclo[2.2.1]heptanes

• Image Source:

  Several convenient methods for the synthesis of 2-amido substituted furans

• Mark:

  Scheme 1

• Associated context:

  Furans and isobenzofurans have frequently been employed as dienes in the Diels-Alder reaction to afford substituted 7-oxabicyclo[2.2.1]heptanes (1) that serve as key intermediates in the synthesis of a variety of natural products. The large number of selective transformations possible with the oxabicyclic system endow this nucleus with impressive versatility. A crucial synthetic transformation employing these intermediates (Scheme 1) involves the cleavage of the oxygen bridge to produce functionalized cyclohexene derivatives 2. Many groups have developed different approaches including β-elimination of suitable derivatives, treatment with strong acids, reductive elimination of endo functionalities (R₂=Cl or SO₂Ph), fragmentation, hydrolytic ring openings and alkylative bridge cleavage reactions.