Favorskii rearrangement experimental

The existence of a cyclopropanone intermediate was supported by subsequent experimental evidence, although in more polar media the presence of dipolar intermediates has also been inferred. For example, when an aromatic a-bromoketone was treated with base in the presence of furan, the major product was a dipolar cycloaddition adduct which was isolated along with the Favorskii rearrangement product."... 

A number of theoretical investigations of Favorskii rearrangement mechanisms have supported the above experimental observations. However, a recent study has elucidated a mechanistic variation whose activation energy for its rate-determining step (RDS attack of the... 

The analysis of the Favorskii rearrangement semibenzilic mechanism sheds light on some experimental and structural factors which allow a differentiation from the symmetrical mechanism. 

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