1+ 2 (1) isolated. The structure of the mixture was inferred from the singlet absorptions due to the vinyl proton (6 5.75) and the methyl proton (6 2.10) in the NMR spectrum as well as the characteristic carbonyl absorptions at 1675 and 1710 cm-I in the IR spectrum. Base- catalyzed cyclizations of the mixture of octalones and diketones with sodium methoxide in methanol at 45-50" C afforded a 33% yield of 1 and 2 in a ratio 19: l as determined by 13C ...
