Quasi-Favorski reaction

Quasi-Favorsky reaction. Reaction of 4(e)-bromoadamantanone (1) with silver perchlorate in water-acetone (1 2) gives only minor amounts of the expected 4-hydroxyadamantanone (3), the major product being bicyclo[3.3.1]nonene-2-car-... 

Reaction with adamantanone. Japanese chemists1 treated adamantanone (1) with sodium azide in methanesulfonic acid with the expectation of achieving the Schmidt reaction. However, the unexpected 4-methylsulfonoxyadamantanone was obtained in 90% yield. Alkaline hydrolysis cleaves (2) to A2-bicyclo[3.3.1]-mmcnc-7-carboxylic acid (3) in 85% yield by a quasi-Favorsky reaction. Adaman-lanc itself does not undergo this unusual substitution reaction. 

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