A ligand-free, copper-catalyzed cascade sequence to indole-2-carboxylic esters

✍ Scribed by Stefan G. Koenig; John W. Dankwardt; Yanbing Liu; Hang Zhao; Surendra P. Singh

• Book ID: 104098445
• Publisher: Elsevier Science
• Year: 2010
• Tongue: French
• Weight: 253 KB
• Volume: 51
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/j.tetlet.2010.10.035

✦ Synopsis

A variety of indole-2-carboxylic esters are accessible in yields up to 61% through a ligand-free, coppercatalyzed reaction of a series of commercially available 2-halo aryl aldehydes with benign glycine amidoesters, including the common reagent ethyl acetamidoacetate. This one-pot, three-reaction format allows ready entry to the desired heterocycles from starting substrates in the reactivity order of iodo > bromo P chloro substituents. An assortment of functional groups is tolerated, adding to the generality of this methodology.