(24) Since the completion of this work the synthesis of 5-methyl-6-oxobicyclo [3.3. 0] oct-l-en- 3-one has been reported utilizing an intramolecular Wittig reaction of a stabilized phosphorane with potassium carbonate at 40" C: Trost, BM; Curran, DP J. Am. Chem. SOC. 1980, 102, 5699. Since a stabilized phosphorane is generally less nucleophilic than the corresponding 0-ketophosphonate anion, this route would Drobablv not be effective for ...
