Synthese von Bicyclo[3.3.o]oct-1(5)en-2-on aus Cyclohexanon

Synthesis of Bicyclo3.3.0]oct-1(5)en-2-one from Cyclohexanone Treatment of 2-nitrocyclohexanone ( 2 ) with acrylaldehyde yielded in the presence of tetrabutylammonium fluoride the bicyclic product 5 , which was oxidized to the nitro-diketone 3 . The conversion of 3 to the title compound 1 was achieved in the nearly quantitative yield under unusual conditions: K₂CO₃/H₂O and H₂SO₄. Compound 3 , was also converted to 1 (stepwise and one-pot reaction, respectively) by treatment with 1. NaOCH₃, 2. TiCl₃, and 3. H₂SO₄ (Scheme).