The Chemical Selectivity Of Intramolecular Reactions Of Copper-catalyzed Diazoacetamide

The application of copper catalysts in the intramolecular reaction of diazo acetamide is extended.N-Alky1-N-arylmethyl-2-diazo-3-ethoxy-3-oxopropanamides generate generally both cyclohepta[c]pyrrolones(Buchner products)and?-lactams(1,4-C-H insertion products),and show obvious N-substituent-controlled chemoselectivity between the intramolecular Buchner ring expansion and aliphatic 1,4-C-H insertion under the catalysis of copper salts.The less steric N-alkyl substituents generally favor the aliphatic 1,4-C-H insertion,while the more steric N-alkyl substituents generally favor the Buchner reaction.Rhodium(?)and ruthenium(?)catalysts catalyzed 2-diazo-3-oxopropionamide to offer main products through C-H-insertion reactions.Compared with them,the current copper-catalyzed conditions improved the Buchner reaction selectivity of 2-diazo-3-ethoxy-3-oxopropanamides.