Ring expansion ketones, cyclic, with diazo

C. Ring expansion of cyclic ketones with diazo compounds... 

C. Ring Expansion of Cyclic Ketones with Diazo Compounds... 

Olefins may be converted in high yield to a-ahtoroketones by treatment with chromyl chloride in acetone. a-Carboxyketones, generally relatively inaccessible, can be prepared by treatment of ketones with lithium 4-methyl-2,6-di-tert-butylphenoxide and carbon dioxide. Cyclic ketones result from ring expansion of methylene cycloalkanes with cyanogen azide followed by hydrolysis, a procedure which complements the standard diazo-methane-ketone approach. Functionalized cis-bicyclic ketones can be synthesized by haloketal cyclizatlon followed by hydrolysis. ... 

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