Electrochemical reduction epoxides

In the following, some selected classes of reactions and applications of Ni11 polyazamacrocyclic complexes are discussed. Other applications include, inter alia, the electrochemical reduction of allyl ethers1613 and the epoxidation of alkenes.1614... 

Indolines and indoles were prepared by a direct electrochemical reduction of arenediazonium salts. As a result, radical intermediates were generated from which 3,4-disubstituted tetrahydrofuran skeleta were constructed <02OL2735>. A short and stereoselective total synthesis of furano lignans was realized by radical cyclization of epoxides using a transition-metal radical source <02JOC3242>. Other preparations of tetrahydrofurans using radical cyclization include the synthesis of novel amino acids L-bis-... 

Cathodic reduction of diphenyl diselenide produces a benzeneselenolate, which catalyzes the reduction of a, -epoxy carbonyl compounds into -hydroxy carbonyl compounds in the presence of a proton source (Scheme 16) [21]. This electrochemical method is applicable to the selenation of haloalkanes, epoxides, and enones [22]. Electrochemical reduction of elemental selenium to diselenide dianion (Se ) and selenide dianion (Se ) is also possible [23]. 

Ring opening of epoxides using selenolates that are generated by other methods, such as reduction with samarium reagents [19], electrochemical reduction [22], reduction with phosphine [25] or reduction with NaBH4 under microwave irradiation [34], have also been reported. 

Although electrochemical reduction and enzymic reduction of epoxides to alcohols have been reported, little information is available about their characteristic features. 

The electrode converts MbFe into MbFe, which reacts with oxygen to give MbFe -02. Electrochemical reduction of MbFe F02 produces H2O2, which converts MbFe to the radical MbFe = 0, the active oxidant. This oxyferryl radical epoxidizes styrene by oxygen transfer to the double bond. In this process, a catalytic electrochemical reduction drives a catalytic enzymelike oxidation in a doubly catalytic process. 

If small amounts of PhSSPh were deliberately added from the beginning, the more positive reduction potential could be applied from the start. Indirect electrochemical eliminations were also performed in the case of 1,2-dihalides Ringopening reactions by the redox catalytic method were possible in the case of methylene cyclopropanes and epoxides... 

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