Synthesis of Benzo[b]azocin-2-ones by Aryl Amination and Ring-Expansion of α-(Iodophenyl)-β-oxoesters.

ABSTRACT: Transformation of β-oxoesters with PhI(OCOCF₃ )₂ leads to α-(ortho-iodophenyl)-β-oxoesters. These materials are the starting point for the synthesis of 6-carboxybenzo[b]azocin-2-ones by a sequence of aryl amination and ring transformation. This reaction sequence starts with copper-catalyzed formation of N-alkyl anilines from the iodoarenes and primary amines in the presence of K₃ PO₄ as stoichiometric base. The intermediate products underwent ring transformation by addition of the nitrogen into the carbonyl group of the cycloalkanone, furnishing benzo-annulated eight-membered ring lactams. Under the same reaction conditions, the cyclohexanone and cycloheptanone derivatives gave no aminated products, but ring-transformed to benzofuran derivatives.

SUBMITTER: Dierks A 

PROVIDER: S-EPMC6899745 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature