Reductions in water introduction

The reductive methods have been greatly improved and developed in the last 10 years with respect to the type of bonds that may be reduced and with regard to the regio- and stereoselectivity of the process. In this context reductions in aqueous media represent one of the most innovative results of research. 

Reductions by hydrides, which at one time seemed impossible to carry out in water, are now a reality, and several water-soluble catalysts, which allow high yields and high selectivities, have been synthesized. Even the hydrogenation of aromatic rings can be performed in water under mild conditions. 

Some recent and innovative examples of reductions performed by chemical reagents in aqueous media are illustrated below. Enzymatic reductions in water have recently been reviewed [54]. 

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