Pinacoline transformation

The reaction itself is called the pinacoline transformation. Ethers of the glycols also behave similarly, in some cases with particular ease (B., 39, 2288 A., Ch. (8), 9, 484). For a corresponding reaction among ketones, see p. Ill, See also Ann. Rep., 1930, 114. 

Reaction XXXII. Action of Alkalis on certain a-di-ketones. (A., 25, 25 31, 324 B., 14, 326 19, 1868 41, 1644.)—When benzil is fused with potassium hydroxide, or digested with alcoholic potash, or heated for a long time with aqueous potash, a molecular re-arrangement not unlike the pinacoline transformation (p. 79) takes place, and benzilic acid is formed. 

Meerwein, H. Pinacolin rearrangement. III. Mechanism of the transformation of borneol into camphene. Ann. 1914,405,129-175. 

The conclusion that pinacolin has the constitution assigned to it here, has been reached as the result of the study of the reactions of the compound. Its formation as the result of the elimination of water from pinacol would lead to the view that it is an ether, and has the structure represented by the middle formula in the series above. Pinacolin, however, shows the reactions which are characteristic of ketones. The intermediate product in the transformation of a pinacol to a pinacolin has been isolated in certain cases. 

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