Baker—Venkataraman method

Method 1 is a new method for the direct production of flavone from o-benzoyloxyacetophenone and has been successfully applied to the synthesis of other flavones. Method 2, which involves the Baker-Venkataraman transformation, is recommended because of its high over-all yield and the reproducibility of the results. Mozingo and Adkins method 8 is satisfactory but the yield of 0-hydroxydibenzoylmethane is variable. 

Nencki reaction conditions, followed by partial methylation, phase-transfer catalyzed Baker-Venkataraman reaction with veratroyl chloride, and photocyclization. An outline of this method is depicted in Scheme 8. 

In the laboratory of K. Krohn, the total synthesis of akianonic acid and its derivatives was undertaken, utilizing the Baker-Venkataraman rearrangement of ort/70-acetyl anthraquinone esters in the presence of lithium hydride. Using this method, it was possible to introduce ketide side-chains on anthraquinones in a facile manner. 

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