STEROIDAL CYCLOBUTANONES .5. THE BAEYER-VILLIGER REARRANGEMENT OF ALPHA-SUBSTITUTED BETA-SPIROCYCLOBUTANONES

The reaction of the steroidal spiro-alpha,alpha-dichlorocyclobutanone 1 carried out in basic H2O2/MeOH/THF solution proceeds with cine subst itution leading to the intermediate alpha-chloro-alpha'-methoxycyclobu tanone 7 followed by the Baeyer-Villiger rearrangement giving the spir o-alpha-chloro-gamma-methoxylactone 9 as a mixture of four stereoisome rs. The oxidation of the alpha-chlorocyclobutanone 12 gives the methox ylactone 10 resulting also from a cine substitution preceding the rear rangement. The unusual transformation of 1 to the succinic anhydride d erivative 14 is also observed.