Reduction diketones

An interesting example of 1,2-diketone reduction using methods other than metal/phosphine catalysts is the use of a cobalt complex, in combination with quinine, for the reduction of benzil218. In this example the product was formed in 78% e.e. (Scheme 43). 

The transformations that use asymmetric heterogeneous catalysis will be highlighted P-keto esters and diketone reductions by Raney nickel catalyst modified with R,R-tartaric acid and NaBr. a-Keto acid reductions with cinchona modified Pt catalysts are discussed in Chapter 18. 

Unlike most rhodium homogeneous catalysts, the ruthenium(BlNAP) series is very effective for the asymmetric hydrogenation of functional ketones48. This leads to a number of experimental circumstances where the directing effect of substituents is brought into play. One of the most commonly used examples of asymmetric ketone hydrogenation is that of /1-keto esters. Diketone reduction with ruthenium[(5)-BINAP] demonstrates the high enantiomeric purity due to double asymmetric induction. 

P-diketones, reduction, asym. 43, 51 ketones 43, 570 oxido compds. 43, 570 p-siloxyketones 44, 35... 

Sodium carbonate 1,2,3-Triketones from / -diketones via 2-azo-, 2-amino-, 2-diazo-, and 2-hydroxy-1,3-diketones Cyclic trans-tixed -diketones Reduction of water-solubility... 

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