Acetolysis of the epimeric 3,3-dimethyl-7-tosyloxybicyclo[2.2.1]Heptan-2-ones

✍ Scribed by Paul G. Gassman; Joseph M. Hornback

• Book ID: 104239203
• Publisher: Elsevier Science
• Year: 1969
• Tongue: French
• Weight: 200 KB
• Volume: 10
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)87876-x

✦ Synopsis

Recently we reported that the rate determining step in the unusually rapid solvolysis of anti-7-tosyloxybicyclo[2.2.l]heptan-2-one (I.) was the conversion of 1 into its enol, & The enol then ionized in a fast step to give an intermediate which collapsed to give 2 with complete retention of stereochemistry in the T-position. In contrast !+_ solvolyzed at a relatively slow rate to give a mixture of 2 and 5 with 9% of inversion of stereochemistry at 2 c-7. Although this complete difference in solvolytic behavior was instructive insofar as it illustrated the role of enolization in carbonyl participation, it failed to provide an insight into the chemical consequences of the stereochemical relationship between a nonenolizedl carbonyl group and a leaving tosylate function. We now wish to report on the acetolysis of 3,3-dimethyl-anti-7-tosyloxybicyclo[2.2.l]heptan-2-one (1) and 3,3-dimethyl-E-7-tosyloxybicyclo[2.2.11heptan-2-one (g), an epimeric pair, which have nonenolizable carbonyl groups.