Mechanistic Study of Base-Promoted Rearrangement of 1,5-Dibromopentacyclo2,5.03,9.04,8>decane-6,10-dione to 10-Oxa-9-oxopentacyclo2,4.03,6.05,8>decane-3-carboxylic Acid

Article abstract of DOI:10.1246/bcsj.66.2676

The conversion of 1,5-dibromopentacyclo<5.3.0.0^2,5.0^3,90^4,8>decane-6,10-dione (1) to 10-oxa-9-oxopentacyclo<5.3.0.0^2,4.0^3,6.0^5,8>decane-3-carboxylic acid (6) on treatment with 5percent aqueous potassium hydroxide was shown to proceed through 1, exo-7-dibromo-9-oxotetracyclo<4.3.0.0^2,5.0^3,8>nonane-endo-4-carboxylic acid (2).Treatment of 1 with the base in heavy water gave rise to 2-d-6 deuterated at the 2-position, but 2 gave the protium analog 6 after the same treatment.These results are discussed in relation to reactions of similar compounds which have been previously described in the literature.