A VERSATILE NEW STRATEGY FOR THE SYNTHESIS OF TROPOLONES

Article abstract of DOI:10.1016/S0040-4039(00)88954-6

Swern-type oxidation of various 7-halogenobicyclo<4.1.0>heptane-2,3- or -3,4-diols affords the corresponding bicyclic diketones which undergo in situ ring expansion and loss of hydrogen halide to give α-tropolones in high yield.The quantitative conversion of the isolable 1,4-diketone 26 into the γ-tropolone acetate 27 has been achieved.