Reduction with Selenolates and Tellurolates

Selenolates such as Na2Se, NaSeH, PhSeNa, etc., and tellurolates such as NapTe, NaTeH, PhTeNa, etc., are excellent nucleophiles and can reduce a variety of functional groups by nucleophilic attack or single electron-transfer. On treatment with alkali metal selenolates (or amine salts of HpSe and PhSeH), reduction or reductive selenation of ketones and aldehydes, C=C reduction of a,/l-unsaturated compounds, and reduction of nitrogen compounds such as nitro compounds occur successfully [118, 176]. Compared with these selenolate anions, the corresponding tellurium compounds are highly reactive not only toward the same substrates but also toward halo compounds such as a-bromo ketones and vic-dibromoalkanes [46, 52, 177]. 

Other reductions using selenium compounds involve the stereospecific deoxygenation of epoxides by use of selenocyanates or selenoamides [178]. 

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