Reaction of the N-acyliminium ion pmcursor la &??Wedjhm S-proline via anodic methoxykation~ with RCu in the pnsetue of BF,.Et# gives preferentially the trans adducts 2 (trans:ci.s L96:4). Using such a procedure, a general synthetic route to (2R, 5.~~-hans-2,5-d~l~~~l~ines has been developed, as ezmpli@ed by the chirospecific syntheses of tbe ant feromones tratzs 5-butyl-2-bt@yl&y?rolidine QOa), trans-5-ethyl-2-beptyl&yrt&iine (It%) and trans-5-beptyl-2--(5-be.wny&yrrokiine QOc). The anodic oxidation of amides and carbamates according to the Ross-Eberson-Nyberg procedure is one of the most general and efficient electrochemical reactions known.' In particular, oxidation of cyclic substrates gives access to a-methoxylated compounds which would require multi-step synthesis using conventional chemical reagents. An alternative method of preparation is the Kolbelike anodic decarboxylation of Nacylated amino acids in basic methanol (See Scheme 1).2 The Nyberg3 and Shone* groups have shown, that such a-methoxy amides and carbamates undergo nucleophilic substitution by various x-nucleophiles (Nu:) via the corresponding Nacyliminium ion.5 These possibilities are outlined in Scheme I using Nacylpyrrolidine as an example. 0 -2e/MeOH acid w "i' -cx 'i" OMe COR /f COR -2e/MeOH ZSQ%