EDCI

BuOH, EDCI (EDCI = l-ethyl-3-[3-(dimethylamino)propyl]carbodi-imide hydrochloride), DMAP, CH2CI2, 88% yield.Cbz-Proline was protected without racemization. 

Further, Wasserman and coworkers developed a direct acylation of stabilized phosphonium ylides by carboxylic acids in presence of the EDCI/DMAP (way c). This last method allows the introduction of a-aminoacid structures into the resulting P-oxo phosphorus ylides [19-25],opening the way to the total synthesis of depsipeptide elastase inhibitors [22,24] or cyclic peptidic protease inhibitor EurystatinA [20]. 

R)-2-Phenylbutyric acid and (S)-a-methylben2ylamine react to the corresponding dipeptide via an EDCI coupling [86], In a control experiment, (R)-2-phenylbutyric acid and (Rj-or-methylbenzylamine were also reacted. 

Boc-D-alanine and (S)-a-methylbenzylamine react to give the corresponding dipep tide via an EDCI [3-ethyl-l-(3-dimethylaminopropyl)-carbodiimid] coupling [86], control experiment, Boc-t-alanine and (S)-a-methylbenzylamine also reacted. 

Thioamides have been transformed into the corresponding nitriles. Treatment of primary thioamides by tellurium tetrachloride or selenium tetrachloride in combination with triethylamine affords nitriles.66 Treatment of primary amides and thioamides with l-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) gives nitriles.67 Reactions of thioamides with metal carboxylates in organic solvents enables the selective preparation of nitriles, imides or amides depending on the substitution pattern of the starting material (Scheme 33).68... 

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