Anodic a-methoxylation

Anodic a-methoxylation of (3-/J)-l-methoxycarbonylpyrrolidinol derivatives (6) (R = H, Ac, SiMe2f-butyl) displays a modest stereoselectivity. However,... 

Transformation of amines to aldehydes or ketones can be carried out via the anodic a-methoxylation of the corresponding carbamates, (4), followed by an acid-catalyzed conversion of the a-methoxylated... 

As described above, the carbon-carbon bond formation at the a-position of amines using anodically a-methoxylated carbamates as the starting compounds is highly useful for the synthesis of alkaloid type compounds, however, this method is limited only to the bond formation at the a-position. On the other hand, it has been found that the elimination of methanol from the a-methoxylated carbamates 47 yields the corresponding enecarbamates 48 in high yields 30). 

This procedure describes anodic a-methoxylation of carbamates (2) which are derived from primary and secondary amines (1). ... 

In the amidoalkylation, however, the preparation of the starting a-methoxyamides is often difficult since the reaction of aldehydes higher than formaldehyde is not necessarily successful, and even when formaldehyde is employed the yields and purities of the a-methoxyamides are not always satisfactory. On the other hand, the anodic a-methoxylation of amides and carbamates generally allows the synthesis of a-methoxyamides (carbamates) which caimot be prepared by the method describe by equation (50). 

A stereoselective synthesis of ( ) conhydrine via an oxazolidin-3-one proceeds by anodic a-methoxylation of A-carbomethoxypiperidine (144) to give 145. Structure 145 is converted to oxazolone 146 by the series of... 

Trifluoropropylsulfides having a methoxy or an ester group at the 2-position undergo anodic a-methoxylation efficiently in the presence of fluoride ions. The diaster-oselectivity of the products is moderate [490,491]. 

A useful synthetic manipulation at the a-carbon atom of some imino acids, which does not rely on the presence of neighbouring activating groups, is anodic a-methoxylation in methanol (Shono et al., 1984). The resulting aminal has a reactive... 

Anodic a-methoxylation of phenyl 2,2,2-trifluoroethyl sulfide was carried out using various solid-supported bases as shown in Equation 12.6. Polystyrene and silica -gel are suitable as the solid support for an organic base such as piperidine. It is noteworthy that anodic methoxylation was successfully carried out even after 10 recycles of the solid-supported base. The method has also been successfully applied to electrochemical acetoxylation in acetic add/acetonitrile. 

This procedure describes anodic a-methoxylation of carbamates (Z) which... 

Scheme 23 Building blocks for the chiral pool by anodic a-methoxylation of amides.

Shono T, Matsumura Y, Inoue K (1983) Electroorganic chemistry. 71. Anodic a-methoxylation of iV-carbomelhoxylated or iV-acylated a-aminoacid esters and aamino-b-lactams. J Org Chem 48 1388-1389... 

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