Anodic Functionalization of Olefins

The anodic oxidation of olefins in the presence of nucleophiles, such as CH3OH or CHjCOOH, is in principle a reaction of very great industrial interest since it permits allyl oxidation as well as C—C coupling. Nevertheless, it is hardly used industrially today. This is essentially due to the fact that the selectivities are frequently poor. Over the past few years, the reaction principle has been used in synthesis problems in the area of fine chemicals. For example, the anodic methoxylation of citronellol is a key step in a new rose oxide synthesis by Sumitomo35). 

Kuraray361 used the addition of anodically generated radicals of 1,3-dicarbonyl compounds for C—C coupling in the preparation of intermediates for P-blockers. 

BASF developed a process for the preparation of 2,5-dimethoxy-2,5-dihydrofuran from butene-1,4-diol37)  

The anodic acetoxylation of olefinic terpenes was used for the synthesis of new fragrances (Kuraray 38-42 ) 

These reactions — with the exception of37) — have not progressed beyond the laboratory stage, while a new sorbic acid synthesis based on the addition of carboxy-methyl radicals to 1,3-butadiene 44 48) has reached the pilot stage at Monsanto. The core of the new synthesis is the in-cell regeneration of the chemical oxidant Mn(OAc)3 in the presence of catalytic amounts of Cu(II) salts. 

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