Nickel benzoate oxidation

The keto group of a keto ester may be preferentially reduced by catalytic hydrogenation. Excellent yields of hydroxy esters are obtained. Copper-chromium oxide catalyst has been employed in the preparation of methyl p-(a-hydroxyethyl)-benzoate and several aliphatic -hydroxy esters. The last compounds have also been made by hydrogenation over nickel catalysts.Substituted mandelic esters are prepared by catalytic reduction of aromatic a-keto esters over a palladium catalyst. Similarly, platinum oxide and copper-chromium oxide have been used in the aliphatic series for the preparation of the a-hydroxy diester, diethyl... 

Androsten-3/ -ol-17-one acetate is reduced over Raney nickel to the 17jS-alcohol, which is protected as a benzoate. This allows the selective hydrolysis of the acetate with methanolic sodium hydroxide solution. A final Oppenau-er oxidation leads to testosterone benzoate, hydrolysis of which gives the target compound. 

Oxidative Methods.—A convenient and inexpensive procedure for the oxidation of secondary alcohols to ketones, applicable to multi-mole preparations, uses aqueous sodium hypochlorite in acetic acid/ Selective oxidation of secondary alcohols is possible as primary alcohols are oxidized much more slowly. Alcohol oxidations with molecular bromine in combination with nickel(ll) benzoate in acetonitrile are remarkably free from competing reactions. However, 1,4-diols yield butyrolactones. ... 

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