The Reduction of Keto Derivatives

The over-all transformation covered in this section is that of conversion of a ketone into a simple olefin by the use of carbonyl derivatives  

The Bamford-Stevens decomposition of tosylhydrazones by base has been applied to steroids, although not extensively. It has been demonstrated that the reaction proceeds via a diazo compound which undergoes rapid decomposition. The course of this decomposition depends upon the conditions in proton-donating solvents the reaction has the characteristics of a process involving carbonium ions, and olefins are formed, often accompanied by Wagner-Meerwein-type rearrangement. In aprotic solvents the diazo compound appears to give carbene intermediates which form olefins and insertion products  

Most steroid reactions of this type have been carried out in proton-donating solvents (see ref. 313 for an exception) and rearrangement is a common occurrence 

The reaction is not usually very satisfactory, although favorable results have been reported on occasion. Tosylhydrazones of 7-ketones give A -olefins  

The reduction of tosylhydrazones by complex metal hydrides has been used very effectively to prepare saturated steroid hydrocarbons in high yields.  

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